V 80 no 2 fall 2011

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THE COLLEGE OF FAMILY PHYSICIANS OF CANADA

LE COLLEGE DES MEDECINS DE FAMILLE DU CANADA

WHY FAMILY MEDICINE? Famil y medi cine offe rs challenges, flexibili ty, and tremendo us di versity. Famil y ph ys icians provide comprehensive care for patients and their fa milies w ithin the community, w ith a foc us o n preventio n, management of chroni c disease, and coordination of care. Famil y ph ysicians have the oppo rtun ity to provide ca re in a variety of settings, including medi ca l clini cs, emergency departments, acute care settings, and in patients' ho mes. So me work internationall y prov iding ca re to people in low-resource countries. With many physicians workin g in tea ms and w ith other hea lth profess io nals such as nurses, occupatio nal therapi sts, and nutriti o ni sts, the field is also beco ming more co ll abo rati ve. Training for a career in family medicine Famil y phys icians are often the first line of ca re and ca re fo r patients w hen they present w ith illness through the management of c hroni c diseases. Students shou ld consider fa mil y medi cine if they: • Are interested in bei ng generali sts; famil y phys icians spec iali ze in breadth rather than depth of knowledge, amassing an equal but diffe rent knowledge base to specia li sts • Enj oy di agnos ing and managing the undifferentia ted patient: fa mily phys ic ians have the opportun ity to see patients from their first prese ntatio n, and to manage their ca re both independentl y and in partnership w ith other medi ca l professio nals in the community • Are attracted to a numbe r of di ffe rent specia lti es and wa nt their practi ces to enco mpass a w ide range of di sease presentations • W ant fl ex ibili ty and co ntrol over their schedules • W ant to fo rm lo ng-term relationships w ith their pati ents Di ve rsi ty in patients, work setti ngs, and schedu les ma kes famil y med ic ine the most flex ible career in medi ci ne. A variety of practice models, the opportuni ty to job share, and the abil ity to shape thei r practi ces offer fa mily ph ysicia ns a great dea l of choi ce. The high demand for fa mily physicians in almost every regio n of Ca nada also opens many oppo rtunities fo r locum posi tio ns and travel. Some fa mil y physic ians also choose to incorporate a focused area into thei r scope of practi ce. Nea rl y o ne-third of famil y medi cine res idents compl ete additio nal training to better prepare them fo r the pati ents they wi ll encounter w hile serving thei r community's specific needs. Students may also pursue training through Enhanced Skills (R3) programs, ranging from a few mo nth s to o ne year. In 2008-2009, 196 R3 pos itio ns were ava il able in Ca nada fo r fa mi ly medi cine res idents. At so me schoo ls, prospec tive students ca n secure fundin g to support an R3 training program based o n their unique ca ree r goa ls; ava il ability and foc us va ry by schoo l. Exa mples of Enhanced Ski ll s programs include emergency medicine, sports medi c ine, geri atri cs, wo men' s hea lth (o bstetri cs, gynecology), adolescent medic ine, mental hea lth, resea rch training, substance abuse treatment, intern ational hea lth, and HIV/ AIDS. Income for family physicians varies w idely depending on hours, locatio n, incenti ves, and type of practi ce. Within a group practice, family phys icians sho ul d ea rn over $175,000 after overh ead and befo re taxes. Incentives fo r practic ing in underserved areas range fro m higher sa laries and hi gher fee-for-servi ce payments to loan forgiveness, lumpsum payments, increased continuing med ica l educa ti on, and ho liday suppo rt . M ost rural phys icians have low er overhead costs and the oppo rtuni ty to earn higher income fo r performin g procedures that would otherwi se be ca rri ed out by other spec iali sts . In the midst of Ca nada-wide and global sho rtages of fami ly phys icians, the Ca nadi an government is rea li zing that a robu st primary ca re system is vital to the sustain abi li ty of our hea lth care system. Will you be the future of family medicine?

For more information please see http://www.cfpc.ca/whyfamilymedicine This is a condensed v~ rsion of this ~oc ument. For the complete pamphlet with more detailed information, please send an email to soms@cfpc.ca to rece1ve a full vers1on electronically. Autho red by: lan Scott MD M Sc DO HS CCF P FRCPC FCFP (Vancouver, BC) Go ldi s Chami BA BSc (Vancouver, BC) Spec ial thanks to all of the medi ca l students who have contributed their feedback. This article has been made poss ible through a financial contrib ution from Hea lth Ca nada . The views expressed herein do not necessa rily represent the views of Hea lth Canada.


The University of Western Ontario Medical Journal Volume 80, Issue 2, Fall 2011 www .uwomj.com ~~~~~----~--------------------------

' EDITORIAL

Allin the Head Pencil/a Lang

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ARTICLES Microvascular free flap transfer for reconstruction of oromandibular defects Brennan Ballantyne, Sandeep Dhaliwal Faculty Reviewer: Dr. Anthony Nichols. MD

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Malignant airway obstruction : treating central airway obstruction in the oncologic setting Esther Chan, Niron Argintaru Faculty Reviewer: Dr. Bela/ Ahmad

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listen ing with our teeth! The SoundBite Hearing Aid : a new technology for single-sided deafness Melissa J. MacPherson, Mayaarendra Ravichandiran Faculty Reviewer: Dr. Lome Parnes, MD

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Falling on deaf ears: overview of cochlear implantation issues in Canada and locally Niran Argintaru, Mosko Hamidi and Laura Allen Faculty Reviewer: Dr. Sumit K Agrawal MD

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" Is Beauty Truly in the Eye of the Beholder?"- The Universal Nature of Facial Beauty M ichal Brichacek, Robert Moreland Faculty Reviewer: Dr. DamirMatic, MD MSc FRCSC

Incidence of acute respiratory distress syndrome and acute lung injury in patients requiring prolonged mechanical ventilation Paul Kudlaw, Chu L, Herridge MS, M.D., M.P.H Faculty Reviewer: Nigel Paterson, M.D.

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Shortness of breath in a 12 year-old boy: a classic presentation of stage IV Hodgkin's Disease? M ichael Livingston Faculty Reviewer: Dr. Neil Merritt, M.D., FRCSC

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Obstructive sleep apnea in children : the when, how and why of screening Kirsten Jewell Faculty Reviewer: Dr. Murad Husein

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An interdisciplinary approach to voice disorders Emma Farley (Meds 2013}, Ashley Kim (Meds 2013} Faculty Reviewer: Or. K. Fung

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Transoral Robotic Surgery (TORS) Jason Xu, Michal Brichacek Faculty Reviewer: Dr. Kevin Fung, Dr. Anthony Nichols

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The role of FOG-PET and PET/CT in the diagnosis and staging of head and neck cancer Adrian Matthews, Jai Prashanth Jayakar and Joshua Rosenblat Faculty Reviewer: Dr. John Yoo

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Marijuana use: sequelae and implications for health promotion Karline Treurnicht Naylor, Daniel James and Stephanie Gottheil Faculty Reviewer: Dr. Donald Farquhar

An Interview with Dr. David Leasa Lauren Sham, Abdul Naeem, Joyce TW Cheung

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A lung mass and digital clubbing in a young woman Julie Lebert, Joyce TW Cheung Faculty Reviewer: Dr. David Leasa, Dr. S. Nelson

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The economics of health and healthcare: a primer for the medical student Hang Shi Faculty Reviewer: Or. Greg Zaric M.ASc, MS, Ph.D.

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The University of Western Ontario Medical Journal EDITORIAL TEAM

EXECUTIVE TEAM EDITOR-IN-CHIEF SENIOR ASSOCIATE EDITOR JUNIOR ASSOCIATE EDITORS LAYOUT EDITOR

LAURA HINZ (MEDS 2011) PASQUALE MONTALEONE (MEDS 2011) PENCILLA LANG (MEDS 2011) PAUL KUDLOW (MEDS 2013) JOYCE T.W . CHEUNG (MEDS 2013) MAYOORENDRA RAVICHANDIRAN (MEDS 2013)

DEPARTMENTAL EDITORS CLINICAL PROCEDURES

SAN DEEP DHALIWAL (MEDS 2013), BRENNAN BALLANTYNE (MEDS 2014)

DIAGNOSTIC REVIEW

JAI JAYAKAR (MEDS 2013), ADRIAN MATIHEWS (MEDS 2013), JOSH ROSEN BLAT (MEDS 2014)

ETHICS AND LAW

MOSKA HAMIDI (MEDS 2013), LAURA ALLEN (MEDS 2013), NIRAN ARGINTARU (MEDS 2014)

HEALTH PROMOTION

PAUL KU DLOW (MEDS 2013), STEPHANIE GOTIHEIL (MEDS 2014)

HISTORY OF MEDICINE

PENCILLA LANG (MEDS 2011)

INTERDISCIPLINARY

EMMA FARLEY (MEDS 2013), ASHLEY KIM (MEDS 2013)

MEDICINE AND TECHNOLOGY

MAYOORENDRA RAVICHANDIRAN (MEDS 2013), MELISSA MACPHERSON (MEDS 2014)

PROFILES

JOYCE TW CHEUNG (MEDS 2013), ABDUL NAEEM (MEDS 2014), LAUREN SHAM (MEDS 2014)

THINKING ON YOUR FEET

ESTHER CHAN (MEDS 2013), ROMAN SHAPIRO (MEDS 2014)

ZEBRA FILES

MICHAL BRICHACEK (MEDS 2013), JULIE LEBERT (MEDS 2013)

HEALTH POLICY AND ECONOMICS

PAUL KUDLOW (MEDS 2013), KARLI NE NAYLOR (MEDS 2013), HANG SHI (MEDS 2013)

EDITORIAL BOARD DR . LOIS CHAMPION

DR . FAISAL REHMAN

DR . MICHAEL RIEDER

DR . JIM SILCOX

DR . JEFFREY NISKER

DR . DOUGLAS QUAN

COVER ART: MICHAL BRICHACEK FRONT: The left half of th e image shows what we as physicians can see . There are few other areas of the body where knowledge of anatomy is as crucial in und erstanding di sease pathology. The airway, ea r, and nose all require an optimal shape to function; the lungs need space to expand . Physiology allows us to understand the integration of structure with function . The right half of the image shows what we cannot see, and rather what we must think. It is essential to look beyond the obvious, consi dering the underlying anatomy and physiology, in order to understa nd .

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Allin the Head Pencilla Lang (Meds 2011)

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n the middl e ages, a common treatment for fo reign bodies in the throat was to ca ll upon St. Bla ise, the "defender of the throat":

"Piece of bone or thorn. whatever thou art, just as Jesus Christ caused Lazarus to come forth from the tomb and Jonah from the belly of the whale (here the patient should be eized by the throat) in the name of St. Blaise, martyr and servant of Christ, 1 order three to come up or go down" - Aetius of Amida (4th century AD) 1 Other early remedi es included th e use of th e dun g of lambs, th e j ui ces of a snai l pi erced w ith a needl e, the as hes of burnt wa llow mi xed w ith hay, or cent ipedes mi xed with pi geons' dung applied externa ll y. 2 In G rade 5 I wrote a poem in which I described th e virtues and draw backs of each medi ca l spec ialty. In it, oto laryngology held the dou ble distincti on of being the mo t di ffic ult specialty to pronoun ce and spe ll. Banis hed fro m my th oughts fo r th ese reasons, I gave di eases of the ears, no e and throat little thought until I was capti vated by th e compl exity and mystery of th e sphenoid bone in medi ca l chool. Over centuries, th e stud y o f anatomy and phys io logy have debunked many superstitions. We now know th at poisons dropped into th e ear do not have th e same effect as poisons swa llowed (as was be lieved durin g Shakespeare's time), and that ting ling in th e left ear is not caused by our peers speaking poorl y of us. Equa ll y many mysteri es remain . What causes allergic rhini tis ra tes to ri se a nd fa ll a m o ng p o pul a ti o ns? W ha t is th e pathoph ys io logy of mitochondrial hearing loss? Are minimall y in vasive procedures an effective way to remove tumours with less damage to surround ing tiss ues?

Despite th e changi ng landscape, th e UWOM J rema ins a publi cation of wo rk written by and fo r UWO medi ca l and denta l students. Our obj ectives are twofo ld : to edu cate and enlighten by enco urag ing th e sharing of in fo rm ati on and idea between student , teachers and our medi ca l community, and to a ll ow UWO medi cal students to ex perience th e process of craft ing their own research, rev iew and case study arti cles. We in vite yo u to join us this yea r a an author, suppo rter or reader.

REFERENCES I. Ro ll eston, J. D. Laryngo logy and Fo lk-Lore. The Journal of Laryngo logy & Otology. 1942;57( 12) : 527-532 . 2. Dani el CL, teva n CM. En cyc l op~tdia of uperst itions, Fo lklore, and the Occu lt Sciences of the Worl d (Volu me I). Detroit: Ga le Resea rch Co; 1903 .

The study of ENT covers a vast spectrum of di seases and crosses many medi cal spec ialtie , from wimmer's ears and sore throats that frequ ent primary care offices, to problematic diffi cult airways in anesthesia, and tumours vis ualized onl y through imag ing. Thi s iss ue of th e UWOMJ is an eclecti c mi x of topics. We bring you articles on the SoundBi te hearing aid that a ll ows a person to 'hear' with the ir teeth, free-flap oromandibu lar reconstructi on tec hniques, a new tra nsoral roboti c surgery procedure, the debate surroundin g fund ing o f cochlear impl ants in Canada, and many more. Since it 's establi shment in 1930, the UWOMJ has been continua ll y changing and growing to meet th e needs of our communi ty. I fi rst got in volved w ith th e VWOMJ as a j uni or departmental editor in 2007, and over the yea rs I have had the pri vi lege to w itness extraordinary growth in thi s j ourn al. Highli ghts have incl uded th e forg ing of a partn ership w ith CU Adverti sing all owing the printing and di stributi on o f th e UWO MJ free of charge to readers, a beautiful new layout, a new online presence at http :// www. uwomj .com/ (please do drop by and visit !), and the creation of feature arti cle, departmenta l and artwork awa rds to recogni ze the contributi ons of UWO medi cal students. The editori al team expects the 2011-201 2 yea r to bring even more change - keep your eyes peeled for an interacti ve online component to th e j ourn al!

UWOMJ I 80 :2 I Fall 2011

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6ii"JICAL PROCEDUR,ES . _:--:·~· .-. . __ -- .

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Microvascular free flap transfer for reconstruction of oromandibular defects Bre nnan Ballantyne {Meds 2014}, Sandeep Dhal iwal {Meds 2013} Faculty Reviewer : Dr. Anthony Nichols, Department of Otolaryngology- Head and Neck Surgery, UWO

eco nstru cti on of the ma ndibl e prese nt unique cha ll enges to th e head and neck su rgeon. A lthough mandibul ar defect ca n resu lt from trauma, infection, congeni ta l defo rmiti es, or osteo necros is, it most co mm onl y occ urs fo ll ow ing ablative surgery fo r the treatment of benign o r malignant neoplasms. Primary intrabony mandibular carci no ma is rare; there fo re, th e in vo lvement of th e lowe r jaw is usua ll y secondary to neoplas m ex tensio n from th e o ra l cavity or the o rop harynx. A ltho ugh tum our resec ti on to ensure patient surviva l is a surgeon's primary conce rn , not to be overl ooked are aestheti c and quality of life parameters. The ma ndibl e serves to prov ide shape for the lower third of the face, a borde r between the face and neck, and po itions th e mentum and lowe r lip. Functionally, it supports masticatory forces and the mandibu lar dentiti on as we ll as the tong ue in both pos ition and function . On ave rage, it must su ta in a force of 726 with a maximal force occurrin g at the molar teeth of 4346 N. 1

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The use of nonvascu larized techniques for repa iring th e mandible provides excell ent res ults in certai n pati ents. For exa mpl e, allo pl asti c impl ants, such as th ose co mposed of tita nium , provide rapid recon tru ctio n optio ns w itho ut the need for ha rvest ing autoge nous free fl aps. However, th e di sadva ntage of this meth od is the ri sk of pl ate fracture, pl ate extrus ion, and ex posure w ith subseq ue nt infection . A ltern at ive ly, free tissue transfer provides superior re ults in repai rin g mandibular defects in most ituati on as an abdunda nce of literature is available to sugges t th at such techniques impro ve patients' quality of li fe.2 ·3 Figures 1-4 outline th e basic pr i ncip les of tum o ur resec ti o n a nd oro m a ndibul ar recon !ruction . C urrentl y, there are seve ra l urgica l o pti o n ava ilable for th e repai r of oro mandibul a r defect us ing mi crova cul a r free fl ap methods.

FIB ULAR OSTEOCUTANEOUS FREE FLAP

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SCAPULAR OSTEOCUTANEOUS FREE FLAP The cap ul ar osteocutaneo us free fl ap ( OFF) is a ve rsa tile fl ap for ma ndibul a r reconstruction as it enables repair of many bone defects whil e imulta neou ly providing a n abundance of soft tiss ue for repa iring defects that involve fac ia l ski n and o ra l mu cosa. The SOFF can provide up to 14 em of ca pular bone, and is ba ed o n the circumflex sca pular artery and vei n. 12 The bra nc hing pattern of th e vascul ature permits harvesting a number of fasciocutaneous and osteoc utaneo us flaps . Often, part of the lati s imus do rs i and/or erratu ante ri o r va c ul ari zed by the thoracodorsal a rtery and ve in ca n be inco rpo rated to provide mo re soft ti ssue bulk. Neverthe le , the limited length, wid th and integrity of bone ava ilable makes the scapul ar fl ap un suitab le for denta l implants. Decrea ed range of shoulder moti o n ca n occur if aggress ive post-o perati ve physical therapy is not carri ed o ut. However, nea r no nna l function ca n be obtai ned if proper rehabi litati o n i pursued. A drawback of the fl ap is the n eed to change the positio n of th e pati ent durin g surgery fro m upm e to latera l fo r harvestin g. Thi s prevents harvest of the flap at th e sa me time as th e tumo r ablati o n, w hi c h may pro long th e case.

SCAPULAR TIP OSSEOUS FREE FLAP

The fibul ar free fl a p has been deemed th e " workh o rse" donor s ite for reco nstru ctio n of oroma ndibul a r defec ts because o f it versa ti lity, frequ ent use, and success rates th at approac h upwa rd s of 95%. 4-6 The fibu lar fl ap i vascul arized by the peronea l artery a nd its two assoc iated venae co mitantes. The e ntire fibul a (- 25cm) ca n be harvested except for ma ll segments at th e di ta l and prox ima l ends to prese rve joint stab ility and ca n be used w ith th e fl exor ha lluc is lo ng us muscle or a sk in paddl e for additi o na l oft ti ssue repair.7 As such, it is th e natura l choice when lo nger le ngths of bone are needed to re pa ir a s urg ica l resec ti o n a nd a n exce ll e nt c ho ice for reco nstructions that require primaril y bone or where th e ma ndibl e is atrophi c.8 The fibu lar fl a p prov ide enough bone fo r supporting dental impla ntati on an d is an idea l match fo r th e co nto ur of the natura l j aw a nato my. Criti c isms o f th e fibul a r free flap have surrounded th e he ig ht di sc repancy com pared to th e nati ve mandible , and th e ina bility to

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reco nstruct la rge-sca le so ft ti ssue defects (ie. those res ulting from tota l g lo secto mi es) . otwi thsta ndin g, continued innovation has res ulted in the development of a " doubl e-barre l" tec hnique that folds th e fibu la onto it e lf and the reby effecti ve ly doubles the height of the mandibl e avai lable for osseo integrated implants. 9 Large soft ti ssue defect ca n be re pa ired by u ing a second fl a p such a the radial fo rearm free fl ap o r pectora l is myocutaneo us flap . 1 Finally donor site morbidi ty is a pa rti cu lar co ncern . A ltho ug h most patients will experi ence a hindrance in ankl e planta r- and do rs i-flexion range of moti on and trength te tin g, tudies have hown that thi decrease is not enough to impact patients' quality of life. 11

Preferred by the head and nec k tea m at the University of Western Ontario, one increasing ly popular a lternative to the trad itiona l sca pula r fl ap is th e sca pu la r tip osseous free fl a p based o n the angular branch of th e thoracodorsal a rtery. Thi s modified fl ap enable the use o f up to 20 em of bone, is often harvested with the lati s imus do rsi and/o r . serratu anterio r muscles, a nd provides the optio n of 1 ~ crea _m g the kin a nd musc le pedicl e le ngth by a lso ex tending the di ssecti on to th e subsca pular artery and ve in. Thi s a ll ows the pedi c le ~ength to reach upwards of I 7 em compared to 6 em from th e OFF. 3 Furthe rmore, th e tri a ngu_lar nature of th e infe rior a ng le o f the scapu la a ll ow for harvest mg a grea ter va ri ety of 3-dime ns iona l s ha pes: . These reco ns tru c tion adva nt ages - in creased bone ava il abil ity, mcreased pedi c le le ngth , a nd bone geometry _ offered by tl~e sca pula r tip free fl ap have been shown to be associated with hi g hl y successfu l surg ica l outco mes .1 4

UWOMJ I 80 :21 Fall 2011


ILIAC CREST OSTEOCUTANEOU FREE FLAP The iliac crest osteocutaneou free fl ap (I OFF) offers unique advantages ~ver th e fibul ar fl ap w ith re pect to quality and quantity of bone ava ilable. The natura l shape of the ili ac crest resembles the mandibl e anatomicall y, and th erefore minima l osteotomy is required to form the neomand1ble. For exampl e, th e hemimandible can be recreated from th e ip ilateral ilium using the anteri or superi or ili ac pme to restore the mandibular ang le. 15 The avai lab le bone has a height comparable to th e nat ive dentate mandibl e, and is th erefore an optunal substrate for denta l implantat ion. However, th e surgery is very complex compared to newer options, and has been largely supplanted by the fibular free fl ap as the primary choice. The ICOFF bl ood . uppl y is based upon deep c ircumflex iliac artery and vein 7 The mtem al oblique mu cle is thin and pliab le and can be manoeuvred independentl y of the bone easi ly and reliab ly.I S A s1gmficant draw bac k to the u e of th e ICO FF is th at harve t invol ve the rel ease of the ~ bdomin a l muscles to access th e periton eal space leadmg to morbidity at the donor site, inc luding issues of hemi a preve ntiOn a t the abdominal wa ll , ga it a lte ration , se nso ry disturbance , and ac ute pain . There fore, ignificant rehabilitation is often req uired to rega in norma l ambul ati on.

RADIAL FOREARM FREE FLAP The radi al forearm free fl ap (RFFF) has some of the best blood suppl y compared to oth er tissue options, is we ll innervated fo r good recovery of sensory function , and additional bulk can be added by mcorporatmg the brachioradiali s musc le. 7 The arterial supply to th e RFFF IS ba ed on the radial artery. There fore, an Allen test must be performed before harvesting thi s flap to ensure th e ulnar artery can adeq uate ly. upply the hand. Venou drainage occurs through th e venae com1tantes of the radial artery or via th e cephalic vein . . T~ e .RFFF o~ers a large area, thin and pliable skin segment which IS Ideal . for mtra-oral reconstruction thu making it the most ~1de l y u ed microvasc ular free flap in all head and neck surgery.I 6 It IS used more for defects of the oral cavity, oropharynx, nasopharynx , and tongue as a fasciocutaneous flap , but the option of using it as an osteocutaneous fl ap by including bone is available. I6 Approximately I 0 em of bone can be taken . A lthough it is strong cortica l bone, it tends not to be very thick as on ly 113 of the cro -sectional area of the radial bone can be taken without increasing the ri sk of stress fracture to the arm . As such, RFFF is best suited for latera l or ramus mandibular defects that require minimal amounts of bone but an abundance of so ft tissue. Known limitations include the lack of availab le bone for osteotomy, and morbidity at the donor site due to the bulk of remaining bone . Fracture rate foll ow ing RFFF approaches 18% of cases, 17 but prophy lactic intemal fi xation of the radius has been shown to reduce thi s fracture rate to as low as 4.5%. 18 Tapering edges of graft in a " boat tail" can also reduce the risk of postoperative fractures as can a prolonged period of immobilization (3 weeks). 8 For these reasons, on ly small bony defects of th e mandible are repaired using radial forearm flap, or it is combined with other donor sites (ie. iliac, fibular or scapu lar). 19

POST-OP I OUTCOMES I COMPLICATIONS Success rates for free tissue transfer at most hi gh volume centers is high, exceeding 95% or higher. 1·10 However, close postoperative monit_oring can detect complications that may affect ti ss ue viability, allowmg for early intervention to minimize recipient site morbidity. The most common complications that threaten the viabi lity of the free flap results from vessel thrombosis, predominantly in the veins. 20 Hematomas as a result of the surgery or the failure to place an adequate suction drain are also well-known complications. Other problems that have been cited in the literature as causes of morbidity include pulmonary problems, prolonged ventilatory support, and acute alcohol withdrawaJ.I 9

Postoperati vely, most pat ients are transferred to the intensive care unit fo r an average of 2.44 days, and an average ho pita! stay of 2-4 weeks.21 The most common method of monitorin g the graft includes assess ment of flap co lour, pin prick and bleeding rate, capi ll ary refill , ski n surface temperature, and Doppler igna l investi ga ti ons. Other methods less commonl y used are e lectri ca l impedan ce pl ethysmography, Ia er Doppler, photopleth y mography, tran cutaneous pulse oximetry, and scintigrap hy20 . Pat ient are fo ll owed long term to ens ure that the flap remain VIable, the aesth eti c goals of th e patient have been reached, and th at the patient is achieving fu nctiona l rehabilitation . A 10 year fo llow up of these patients has revea led that aest heti c outcomes are achi eved in 90% of patients, 70% have regular diets and the remainder have soft di ets, 85% have easil y intell igible speech, and greater than 90% have preserved bone height, indi cating that th ere is minimal bone re orpti on 22 These re ults hi ghlight the notion th at microvascul ar free fl ap reconstru cti on has ac hi eved excell ent o utcome th at are ce lebrated by health care teams and their pat ients.

FUTURE DIRECTIONS I CONCLUSION Head and neck reconstructi ve urgery has seen monumenta l adva nces in the past few decade . State-of-th e-art microva cular equi pment, along w1th the de velopment of numerou free flap ti ssue opti ons ha res ulted in vasc ul ari zed osseou free fl ap transfer becoming th e preferred meth od for reconstruction leadi ng to a dramati c rise in rep~i: ucce rate.23 Currentl y, in th e field of oromandibular repai r, excit.mg new advances are continuall y being made to improve surg ica l outcomes . For exa mple, th e co nce pt of di trac tion osteogenesis, originally deve loped for orthopedi c appli cati on to l e ~ gth e n bone, is b eg i~n~n g to be used by head and neck surgeons. Di stractiOn osteogenesis mvolves an extemal mechani ca l device that se parates two bony surfaces. The length of the di straction is th en progressive ly lengthened over everal days to a llow a gap for new bone to form durin g th e consolidation phase. It is used for patients With poor functiOnal outcome followin g reconstructi on due to scar fonnation or inadequate bone length 8 · 12 Moreover, the fi e ld of ti ssue eng ineering also holds promi se for the future of head and neck repair. The use of recombmant bone morphogenic protein (rhBMP-2) has been shown to stimulate bone regenerati on without the use o f autologous grafts in an in vitro setting. 24 Additional ly, in vivo animal and cadave~ic studies have demonstrated the utility of ti ssue eng m ~enng m developmg bone grafts for the use of reconstructing mand.Ibular defects.25 ·26 In thi s manner, th e deve lopment of techniques that allow for the transfer of cultured cell substrate to regenerate portions of the mandible w ill likely offer the next step in th e evolution of mandibular reconstruction .

REFERENCES I. Spi ege l IH , DeRosa J. Mandibular Recon truction . In : Lalwani AK ed. Current diagnosis & treatme nt in otolaryngo logy-head & neck sur~ery. 2nd ed. New York, New York: McGraw-Hill Medical ; 2008 :367-373 . 2. Hartl DM , Dauchy S, Escande C, et al. Quality of life after free-flap tongue reco nstru cti on. The j ourn a l of laryngo logy and otology. 2009; 123(5):550-4. 3. Bozec A, Poissonnet G, Chamorey E, et al. Free-flap head and neck recon tructi on and quali ty of life: a 2-year prospective study. The laryngoscope. 2008; 11 8(5):874-80. 4. Hidalgo DA, Rekow A. A re~iew of 60 consecutive fibula free fl ap mandible reconstructiOns. Plastic and reconstructive surgery. 1995·96(3)· 585-96; di scuss ion 597-602 . ' · 5. Vim K.K, . Wei FC. Fibula osteoseptocutaneous fl ap for mandible reconstructiOn. Microsurgery. 1994; 15(4):245-9. 6. We1 FC, Seah CS, T .ai YC , Liu J, Tsai M . Fibula osteoseptocutaneous fl ap for reconstructi on of composi te mandibul ar defects. Plastic and reconstructive surgery. 1994;93(2):294-304; discussion 305-6. 7. D1sa JJ, C~rde iro PG. Mandible recon truction wi th mi crovascular surgery. Semmars m surgica l onco logy. 2000; 19(3):226-34.

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CLINICAL PROCEDURES 8. Mehta RP, Deschler DG. Mandibular reconstruction in 2004: a n analysis of different techniques. Current opinion in otolary ngology & head and neck surgery. 2004;12(4):288-93. 9. Cha ng Y-M, Tsai C-Y, Wei F-C. One-stage, double-barrel fibu la os teoseptoc uta neo us fl ap a nd immediate dental implants for functional and aesthetic reconstruction of segmental mandibular defects. Plastic and reconstructive surgery. 2008;122(1}:143-5. 10.Deleyiannis FW, Gastman B, Russavage j. Microvascular reconstruction of the head and neck. In : Carrau R, Eibling D. Gerguson B, et al., eds. Operative otolaryngo logy - head a nd neck surgery. 2nd ed. Philadelphia, PA: Elsevier In c.; 2008 :739-52 . 11.Anthony jP, Rawnsley jD, Benhaim P, et al. Donor leg morbidity and function after fibula free flap mandible reconstruction. Plastic and reconstructive surgery. 1995;96(1}:146-52. 12. Miles BA, Go ld ste in DP, Gi lb ert RW, Gullane Pj . Mandible reconstruction. Current opinion in otolaryngology & head a nd neck surgery. 2010;18(4):317-22 . 13. Hanasono MM. Skoracki Rj. The scapular tip osseous free flap as an alternative for an terior mandibular recons tru ction. Plastic and recons tructive surgery. 2010;125(4}:164e-166e. 14.Chepeha DB, Khariwala SS, Chanowski EjP, et al. Thoracodorsal artery scapular tip autogenous transp lant: vascularized bone with a long pedicle and flexible soft tissue. Archives of otolaryngology-head & neck surgery. 2010;136(10}:958-64. 15. Bak M, jacobson AS, Buchbinder D, Urken ML. Co ntemporary reconstruction of the mandible. Oral oncology. 2010;46(2) :71-6. 16.0lson GT, Bayles SW. Recent innovations in the use of the radial forearm free flap . Current opinion in otolaryngology & head and neck surgery. 2001;9(4). 17.Cla rk S, Greenwood M, Banks Rj, Parker R. Fracture of the radial donor site after composite free fl ap harvest: a ten-year review. Surgeon. 2004;2(5):281-6. 18.Avery CME, Danford M, johnson PA. Prophylactic internal fixation of the radial osteocutaneous do nor site. British journal of oral and maxillofacial surgery. 2007;45(7):576-578. 19. Rinaldo A, Shaha AR, Wei WI , Si lver CE, Ferlito A. Microvascular free flaps: a major advance in head and neck reconstruction. Acta otolaryngologica. 2002;122(7) :779-84. 20.Spiegel jH , Polat jK. Microvascular flap reconstruction by oto laryngologists: prevalence, postoperative care, and monitoring techniques. The laryngoscope. 2007; 117(3}:485-90. 21. Ryan MW, Hochman M. Length of stay after free flap reconstruction of the head and neck. The laryngoscope. 2000;110(2) :210-6. 22 . Hidalgo DA. Pusic AL. Free-flap mandibular reconstruction : a 10year follow-up study. Plastic and reconstr uctive surgery . 2002 ;110(2}:438-49; discussion 450-1. 23. Vaughan ED. Functiona l outcomes of fre e tiss ue transfer in head and neck cancer reconstruction. Oral oncology. 2009 ;45(4-5) :421 -30. 24. Herford AS, Boyne Pj. Reconstruction of mandibular continuity defects with bone morphogenetic protein -2 (rhBMP-2) . journa l of ora l an d maxillofacial s urgery. 2008;66(4):616-24. 25. Wilmowsky C vo n, Schwarz S, Kerl jM, et al. Reconstruction of a mandibular defect with a utogenous, autoclaved bone grafts and ti ssue engineering: An in vivo pilot study. journal of biomedical materials researc h. Part A. 2010;93(4} :1510-8. 26. Ewei da AM, Nabawi AS, Marei MK, Khalil MR. Elhammady HA. Mandibu lar reco nstruction using an axia ll y vascularized ti ss ueengineered construct. Annals of surgical innovation and research. 2011;5:2 .

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UWOMJ I 80:21 Fall2011


Malignant airway obstruction: treating central airway obstruction in the oncologic setting Esther Chan (Meds 2013), Niran Argintaru (Meds 2014) Faculty Reviewer: Dr. Belal Ahmad, Department of Radiation Oncology, UWO

b !ruction of the centra l airways, the trachea and main stem bronchi, may result from many disease processes including malignant growth . It is estimated that in the United States, malignant neoplasms will cause centra l airway obstruction (CAO) in 80,000 cancer patients a year. 1 lt is estimated that 20% of these patients wi ll experi ence ignificant morbidity due to per i tent cough, dyspnea, and obstructive pneumonia, and as many as 35-40% of lung cancer patients die due to complications resulting from locoregional di sease. 1•2 While most treatments for malignant CAO are not curati ve, they have been shown to improve resp iratory function , avo id mortality, and improve quality of life.3.4. 5•6 Many different strategies for managing malignant airways exist. Choosing the best one depends on patient factors such as presence of co-morbidities, medical stability, the nature of the underlyin g tumour, and overall prognosis. Non-patient related factors such as ex pertise of medical staff and avai lab ility of technology also greatly impact the mode of treatment chosen.2 This article presents current treatment options for malignant CAO, spec ificall y, therapeutic bronchoscopy, radi otherapy, and surgical resection .

O

CAUSES OF MALIGNANT CENTRAL AIRWAY OBSTRUCTION The most common mali gna nt causes of central a irway obstructions are direct extension into the airway lumen by extrinsic tumours (fig. lb).2 Of these tumours the most common types are bronchogeni c carcinomas (i.e. small cell lung cancer and non-small cell lung cancer), fo llowed by esophageal and thyroid carcinomas 2 Primary tumours of the trachea and bronchi , or intrinsic central airway tumours (fig. Ia) are re latively rare. Seventy to eighty percent of these tumours are of squamous cell or adeno id cystic carcinoma type. 2 Squamous cell carcinomas typically occur later in life and more frequently in men and smokers, while adenoid cystic carcinomas are found in younger patients and are not related to exposure to smoking Occasionally, but less frequent ly, or to the sex of the patient 3 metastases from carcinomas of the breasts, kidn eys, co lon, th yroid and esophagus may spread to the respiratory system and cause CAO .

frequently, pneumonia . 1.3· 7 Because the e ymptoms overlap with those found in asthma and COPO, patients with malignant CAO are common ly misdiagnosed . However, a trong indi cation that symptoms are due to CAO is that they are unresponsive to inhaled steroids and bronchodialators . Other advanced CAO ymptoms are related to si gn of decreased ventilation such as tachycardia, diaphore is and increased work of breathing.7•8 Symptoms of bradycardia, cyanosi s and obtu ndation suggest that the airway lumen is severe ly compromised and in need of immediate interventi on in order to avo id imminent respiratory fa ilure.7 Evaluation and diagnosi s of malignant airways is often based on clini ca l exami nations as well as a tissue biopsy and radiological studi es to confirm the diagnosis 2 While chest radiograph s have little di agnostic va lue, they may be used to quickly rule out other causes of breathing difficul ty such as tracheal deviations or a pneumothorax .2 ·3 Che t and neck computed tomography (CT) scans make it possible to estimate tumour size, depth of in vasion, and the ability to see if the airway di stal to obstru ction is still patent, providing important infonnati on for treatment planning.2.3 CT sca ns are typically always performed in conjunction with bronchoscopy, the go ld standard for eva luati ng CAO . Bronchoscopy allows for direct visualization of the tumour, eva luation of tumour length and locati on, differentiation between an intrinsic endobronchi al and ex trin ic tumours, and most importantly, is equipped to prov ide a tissue dia gnosis 2 •3 Moreover, if needed, di agno tic bronchoscopy may be quickly converted to therapeutic bronchoscopy for CAO management.

a

b

2. 7

CLINICAL MANIFESTATIONS AND DIAGNOSIS Clinical manifestations of malignant CAO depend on size, location , and the rate of progress ion of airway obstruction . Moreover, the patient 's underlying health status and ability to compensate for decreased airflow will influence the extent to which symptoms appear. 1·2 If encroachment into the airway is minor, then there wi ll be little impact on airflow and patients wi ll likely be asymptomatic and never brought to clinical attention . The majority of patients that experience symptoms of CAO have advanced disease and a hi story of underlying malignancy. 7•8 Thus, symptoms of CAO are late findings and include dyspnea, cough , wheezing, stridor and

Figure 1: Schematic diagram of 1ntnnsic (a) and extrinsic (b) tumour obstruction of the central a11ways. Each demonstrates 50% occlusion. Adapted from BeDinger et al. Therapeutic bronchoscopy w fth immediate effect: laser, electrocautery, argon plasma coagulation and stents (2006) .

UWOMJ I 80:2 I Fall 2011

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TREATMENT MODALITIES

v) Airway stent insertion:

I) Therapeutic bronchoscopy:

Airway stents are made of s ilicone, metal or a combination of both and are u ed to mechanically prop open obstructed airways. Stents restore airway patency, improve ventilation, and allow for the c learance of airway secretions.2•7·8 They can be used as standalone treatm ent or in conjunction with debulking and they do not interfere with ub se qu e nt radiation treatments , brachytherapy, or chemothe rapy if an y are needed.8 Moreover, if the patient's ventilation tatu improve followin g treatment, silicon stents can be removed.2 However, metal stents are very difficult to extract and are essentiall y perm ane nt. 2· s One of the greatest advantages to using tents is that th ey may counteract compression by tumours extrinsic to th e a irway. Compli cati o n include ste nt migration , more co mm onl y ee n w ith ili co n ste nts, and stent obstruction by recurrent tum our growth or granul ati o n ti ss ue formation (typica lly seen with ewe r meta l tents used for malignant airway metal stent ).2.8 obstructi o n have s ilicon covering and are made ofNitinol , a flexible e la ti c bio mate ri al, to he lp avo id stent obstruction .2 Additionall y, newe r silicone ste nt are mes hed for fl exibili ty a nd haped or tudded to prevent te nt mi g rati on2 Indicati o ns fo r th erapeuti c bronchosco py are the pre ence of ymptoms of adva nced CAO . ec ros is, bleeding and cartilaginous destru cti on a re not contra indicati ons fo r treatment. 8 In emergency settin gs, therapeuti c bro ncho co py may provide more immediate improvement of th e pati ent 's ventilato r statu and tabili ze them enough fo r furth er treatm ent w ith radi ati o n o r c hemotherapy.s Drawbac ks to th e use of a ri g id bronchoscope are that it require pati e nts to be und e r ge ne ra l a naes thetic . Thu s, therapeutic bro nc hosco py, balloo n bro nchoplasty withstandin g, ca n only be used in pati ent th at have e nough remaining respirato ry capacity to to lerate edati on.

Th e rap e uti c bro nc hosco py utili zes th e ri g id sta inl ess s tee l bronc hoscope to visua lize, treat and debulk tumours. Its wider diameter fa cilitates ventilati o n allowin g for a va ri ety of procedures to be perform ed, including tum our debulkin g, laser resecti on, argonpia ma e lec trocoagul ati on, ba lloo n broncho co py, and stent insertion to re-cannuli e th e a irway2. 7,

i) Tumour debulking: The harp bevelled tip of th e ri g id bronchoscope is u ed to co re out th e tumour and appl y press ure to a irway wa ll s promotin g clot fo m1ati on. However, inadvertent damage to urro unding airways durin g trea tm ent is a ris k and complicati ons may include cutt ing th e lips, g um , larynx or a irway mu co a or cartil age du ring intubati on. Perfo rati on o f the medi a tinum may a lso occ ur if the scope is not in line w ith th e airway lumen 8 ii) Laser Resection: Laser energy de li vered by optical fibre is used to resect obstructing tumo ur . The ma in type of Ia er u ed durin g bronc hoscopic resecti on is th e eody nium :yttrium a luminum garn et (Nd :YAG) lase r w hi ch transmit light energy at I ,064 nm wave length to the ta rget tis ues 2 ,7 The therma l energy from th e Nd-YAG lase r i abso rbed into th e co re of ti sue where temperature may reac h up to 100°C 2 The heat is then tran mitted and cattered a ro und into surrounding tiss ues o th at tota l ti ssue effects may ex tend up to I Omm be low the surface o f laser admini strati on.2.7· 8 Darker pigments, such as those found in blood max ima ll y abso rb energy from Nd- YAG lase rs. As a result, ti ss ues ex posed to th e laser energy are devasc ul ari zed- a process otherwi se known as e lectrocoag ul ati o n 7 Additi ona l admini strati on of the NdYAG Ia e r ca u es charring and eve ntua l va po ri zati on, whi ch is removed by ve ntilation from the bronc hosco pe.2. If tiss ue is not co mpl etely vapori zed, it may be mec hani ca ll y debulked. Beca use tota l ti ss ue e ffects are not immedi ate ly visible durin g trea tm ent and may ex te nd we ll past th e depth of the tumo ur, compli cati ons include late devascul arisati on of adjacent healthy ti ssues we ll afte r th e treatm ent i co mpleted.2.s

Radi ati on ha long bee n used to decrease tum o ur s ize and improve sy mpto m th ~ t res ult fro m a la rge tum our burden, espec ia ll y in palli all ve settm gs. For ma lignant CAO , radi ati on may be delivered in one of two meth od : intrins ic rad iati o n treatme nt (i.e. brachytherapy) or ex te rna l bea m rad io the rapy (E BRT).

i) Brachytherapy:

iii) Argon-Plasma Electrocoagulation: A rgo n- Pl as ma Elec trocoagul ati on (A PE), as o pposed to lase r e lectrocoagul ati on, i a form of no n-co ntact e lectrocoagul ati on. s111g a 5,000-6,000 vo lt park at the ti p of th e pro be, argo n gas, a lso re lea ed at the ti p, become an ioni zed plas ma th at find th e nea rest gro unded tissues produci ng coagul ati ve necros is. 1 Adva ntage of A PC a re th at it may trea t tum o urs latera l to or aro und a co rner fro m th e tip of th e probe that wo uld not oth erw i e be access ibl e fo r laser the rapy. 1·9 T he e lectro n energy utili zed by A PC, however, doe not penetrate ti sue as deepl y as Ia e r ene rgy res ulting onl y in uperfi cial nec ros is o pposed to th e dee p ti ue necros i crea ted by Nd-YAG laser .9 This may be des irable fo r trea ting superfi cial squamo us ce ll carcinom as o r if majo r bl ood vesse ls are close to th e tum o ur bed.9

iv) Balloon Bronchoplasty: Ba lloo n bro nchoplasty u es a ba ll oo n to eve nl y dil ate th e airway with m1mm al tra um a a nd ub eque nt granul ati on tiss ue fonn ati o n in mucosa l ti ss ues. :While most ri g id bronchoscope techniqu es require genera l anae theti c, ba ll oo n bronc hopl asty may be perfonn ed with a fl ex 1bl e bro nc hosco pe und e r co nsc io us sedati o n. 1 Dilati o n is immedi ate ly e ffecti ve a nd may be used for both intrin ic a nd ex trin ic airway ob tru c.ti on . The re ults o f ba lloo n bronc hopl a ty are ~ o t typicall y s u s ta ~ne d and dil ati on is usua ll y followed by stent111 g ?r lase r resectiOn . o mpli cation inc lude airwa y rupture res ult111g 111 pneum oth o rax , medi astinitis and bl eedin g. I

8

2) Radiation Treatment:

Brachyt he rapy re fe r to the place ment of a radi ati o n o urce within or adj acent to th e ~i ue . be ing treated . Thi s is achieved by plac ing ~a dJ a t1 on eeds d Jre.c tl y mto the tumo ur (interstiti a l brachytherapy) o r 111 e~lin g cath eter 1nto the lumen of the orga n be ing treated suc h a ~ n a1rway. For th e trea tm ent of ma lignant C AO, a n e mpty catheter is 1n erted 111to lumen o f th e a irway approx imatel y two centime tre beyo nd th e e tim ated di ta l end o f a target area th at includes the tum o ur.2 The cathete r is the n sec ured at th e nostril and a radi ation ~urce, most co mm onl y iridiu~11 -l 92 , is then loaded into the catheter. 2 · The area ta rge ted by ~ad1 a tJ o n ca n be several centimetre long dependin g on w heth er h1 gh-do e radiation (HDR) or low-do e radi ati.o n ( LOR) is u ed .2 However, LOR has fallen out of favour and HDR IS mo t c mmonl y. used as it utili zes the g reatest advantage of th e brac.hytherapy tec.hn1que, ~h ~t 1. , th e radiation delivered directly at the 1te o f ta rget t1 . sues minimi zes radiation expo ure to nearby hea lth y o rga n oth erw1 e ex posed during external beam radiotherapy. In th1 s way HDR brac hytherapy exposes vital tructure near the airway- such a th e esophagus, thyroid, mediastinum and aorta- to 11111111nal ~mounts of radiation while enabling larger radiation do es · dto 1·be de li vered . to th e target ti s ue ites · A typ 1' cal HDR reg1men e Ive rs a fra ction dose of 7,000-8,000 cG y admini stered once a wee ~ fo r three. week ; however, the exact dose a nd number of fractJ.o ns (rad~a t1on treatment ) will de pend on the ize of the tumour and 1~s locat1on .2·8 Each fraction lasts between 3 to 30 minutes a llowmg brachythe rapy to be delivered a

UWOMJ I 80:2 I Fall 2011


an outpati ent procedure. Brachyt herapy is contraindi cated for tumours that invade major arteries or other tructures within the medi astinum 8 Compli cations include earl y and late radiation effects uch a radi ation bronchitis, hemoptys is, bronchial stenosis, and bronchia l fistu las 8 ii) External beam radiotherapy: Extern al beam radi otherapy (EBRT) has va riable efficacy for treatin g CAO and the therapeutic effects may be quite delayed. However, EBRT continues to be a ma instay of treatment for CAO especia ll y in patients wi th hi ghl y adva nced di sease or comorbiditi e that preclude them from undergoing general anaesthetic. Palliati ve doses of EBRT for the treatment of CAO are typica ll y 3,000 cGy in I 0 consecuti ve fractions . Side-effects a lso include earl y and late radiation effects. Early effect are radiation dermatiti s to the overl ying skin and fatigue . Long-tenn effects mai nl y invo lve thoracic stru ctures close to the airway ( uch as the lungs), whi ch may undergo fibrosis as a result of inadvertent radi ation ex posure. However, current techniques in EBRT such as intensity-modulated radiation therapy in conj unction with shielding or stereotactic body radi otherapy effectively minimize radi ation ex posure to surrounding ti ssue .

3) Surgical resection: Surgical resection is usuall y reserved for tracheal tumours that have not yet metastasized to other areas of the body. If surg ica l resection is successful at removing the entire tumour and achieving negati ve margins, it may be a curative treatment for cancer. The procedure involves removal of the tumour and the in volved trachea l segment followed by re-anastomosis or reconstruction of the trachea l tube. 3 Tumours that involve the carina or subglottic larynx can be successfully resected while preserving ventilation and voca l functioning .3 In addition, it is possibl e to remove up to 50% of the cervical or intrathoracic tracheal length without compromi sing anastomotic hea ling.2.3 While its adva ntage is that it is a potentially curati ve treatment fo r cancer, surg ica l resecti on cann ot be perform ed if complete tumour removal threatens the hea ling of the anastomosis, if the tumour length exceeds 50% of the trachea or if vi tal structures such as the aorta or heart are involved.3 Moreover, the presence of CAO symptoms that alert clini cians to the need for treatment typica ll y appear at adva nced stages of di sease when metastati c spread has likely to have already occurred . Although surgical resection cannot be performed after the mediastinum has received a hi gh-do e of radiation (due to impaired ti ssue healing), it may be followed by adjuvant radiation therapy to decrease the likelihood of loco-regional disease reoccurrence.

DISCUSSION Interventions for mali gnant CAO are highl y technical and require a large amount of medi cal resources and teams of well-tra ined medical personneJ.2 Often the widespread ava il ability of these treatments is limited to patients within a reasonable di stance of specialized center . However, many studi es have shown that these treatments are effecti ve, improve patient quality of life, and may be life-saving in emergent situations. 3.4路5路6 In a prospecti ve cohort study of 20 patients with symptomatic CAO , a ll pati ent demonstrated improvements in airway diameter and 16 patients achieved greater than 80% patency using therapeutic bronchoscope techniques 4 Moreover, the study demonstrated that Nd:YAG laser therapy alone, airway stenting alone, and a combination of stenting, laser, and/or cryotherapy were each indi vidually effecti ve at reestablishing airway patency and improving symptoms. 4 Si milar positive results were demonstrated for the treatment of CAO usi ng stent insertion and radiotherapy. Authors of a multi center tri al found that silicone mesh, studded stents re-established patency, and improved fun cti onal capacity, dyspnea, and g lobal functionin g at I month and 3 months after stent placement. 5 HDR brachytherapy

has also been fou nd to be successfu l in prospective cohort studi e at improvi ng symptom of CAO by more than 90% 6 Lastly, for patients e lig ible fo r surgical resection, surgery offers a high rate of curative uccess J Whil e most of these tri al compared intervention to no treatment and were not randomi zed contro l trials, they have demonstrated that interventi on may improve symptom and quali ty o f li fe . However, to date there are no best practi ce guidelines avai lable on which interventi ons should be used. It has been frequentl y observed that the best approach includes a combinati on of treatment interventi ons 2, and a lthough man y centers are already uti li zing these interventions to manage ma lignant CAO, cho ice of treatment is heterogeneo us and centre-speci fi c. As incidences of ca ncer and specifical ly bro nchogeni c tumour continue to ri se, it can onl y be ex pected that a growi ng number of patients wi ll need to be managed for mali gnant CAO. Sign and symptoms of malignant CAO occur at adva nced stages of disease and patients sufferin g from CAO almost a lways have a positive hi story for underl ying ma li gna ncy. Symptoms of CAO may be treated with a number of techniques including therapeuti c bronchoscopy, radi otherapy, or surgical resection . Each modality has been shown to improve symptomo logy, decrease morbidity, and improve quali ty of life. There are currentl y no best practice guidelines for managing ma li gnant CA O. While patient fac tors will contribute to the dec ision mak ing process, the cho ice of interventi on may be most determined by centre reso urces and ava ilab ili ty o f skilled personnel.

REFERENCES I. Chen K, Varon J, Wenker OC. Mali g na nt airway obstru cti on: Recogniti o n a nd management . J Emerg Med. I 998; I 6( I ):83 -92 . 2. Ernst A, Fe ll er-Kopman D, Becker HD, Mehta AC. Central airway o bstructi on. Am J Respir Crit Ca re Med. 2004; I 69( 12): I 278- I 297. 3. Honings J, Ga issert HA , Van De r Heij den H, Verhagen AD, Kaa nders J, Ma rres H . C lini ca l as pec ts and tre at ment of prim a ry trac hea l mali gnancies. Acta Oto-Laryngo logica. 20 I 0; I 30(7):763-772 . 4 . Amj adi K, Voduc N , Cruysberghs Y, Le mmens R, Fergusson DA , Doucette S, Noppen M. Impact of in terventi onal bronchoscopy o n quality of life in mali gnant airwa y obstruction . Respirati on. 2008 ;76(4):42 I -428. 5. Bo lli ger CT, Bre itenbuecher A, Brutsche M, Heitz M, Stanzel F. Use of sh1dded Po lyfl ex stents in pati ents wi th neopl asti c obstructi ons of the central airways. Respirati on. 2004 ;7 I ( I );83 -87 . 6. Muto P, Ravo V, Pane lli G , Li guo ri G, Fra io li G. Hi g h-dose rate brachytherapy fo r bronchia l cancer: Treatme nt o ptimi zati on usi ng three schemes of th e rapy. O nco logi t. 2005 ;5(3) :209-2 14 . 7. Ke mstie n KH , Reckamp KL. Lung cancer: a multidi sc iplina ry approach to diagnosis and management. New Yo rk: Demos Medi ca l Publishing; c20 I I. Chapter I 9, Tracheo braonchi al Cancers : d:YAG laser resection , brachythe ra py, and photodyna mi c ab lati on ; p. 235 -242 . 8. Yeun g CJ, Esca lante C P. Ho ll and -Frei onco logic eme rgencies. Hamilton: o n infec ti ous pu lm o na ry BC Decke r In c. ; c2002 . C ha pter I 0 , e me rgencies; p. I 9 I -248. 9. Bo ll iger CT, utedj a TG , Stra usz J, Freitag L. Therape uti c bronchoscopy wi th immediate effect: laser, electroca utery, a rgon pl asma coagulat ion and stents. Eur Respir J. 2006;27 : 1258- 127 1.

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Listening with our teeth! The SoundBite Hearing Aid: a new technology for single-sided deafness Melissa J. MacPherson (Meds 2014), Mayoorendra Ravichandiran (Meds 2013) Faculty Reviewer : Dr. Lorne Parnes, MD (Department of Otolaryngology)

earing loss is a significant and common disa bility that affects Thi s approx imately 9% of the Canadi an populati on.' di sabili ty is more preva lent in older populati ons2 and if uncorrected can lead to soc ial iso lati on and communi cati on diffi culties 2 · 3 There are two distinct types of hearin g loss; each with a characteri sti c pathophy io logy. Sensorineural hearin g lo (SNHL) arises fro m conditions affecting th e inner ear or the cochlear nerve, whereas conducti ve hearin g lo s develops from conditi ons a ffecting th e outer ear, the middle ear and the tympanic membrane. These di tincti ons are important since hearing aid technologies address the di ffe rent types of hearin g loss using different strategies . Patients with a conducti ve hearin g los require the amplification o f all so und wave frequencies.2•3 In contrast, pati ents affected by sensorineural hearing loss present a much more complicated technological problem since these patients may have decreased audibility of certain so und fre quencies as oppo ed to an overall decrease in the audibili ty of all sound frequencies 2 Most pati ents w ith sensorineural hearing loss have decreased audibility of hi gh frequencies;2 however, in the case o f Meniere 's di sease there is a decreased audibili ty of lo w frequ encies.4 This res ults in th e ability to hear so und but the inability to understand speech since speech amplitude (loudness) is caused by low frequency so und waves which the patient can detect but speech comprehension is poor due to th e loss in detecti on of th e hi gh frequ ency sound wa ve components.2 Speech comprehension is more diffi cult in th e presence o f background noi e and consequentl y hearing aid technologies address thi s iss ue by increas ing the signalto-noise rati o to bring out speech from no ise.2

H

HEARING AID TECHNOLOG I ES FOR UN I LATERAL SENSORINEURAL HEARING LOSS Patients with unilateral sensorin eural hea rin g loss ( ingle-s ided deafness) also face diffi culti es loca liz ing th e direction o f unseen so unds and detectin g so und loca li zing from th e directi on o f th e affected ear, in addition to the diffi culti es previously mentioned.s The head shadow e ffect cause a parti cular diffi culty for these patients since so und waves ori g inating fro m th e affected ide are attenuated by th e head before reaching th e fun cti onal ea r. Several technologica l strategies used to address some of th ese problems include th e routin g of sound from th e di sabl ed ear to th e full y fun cti onal ear using air conducti on contralateral routin g o f so und (C ROS) dev ices or bone-anchored hearing aids (BAHA).2.5 While CROS devices do not allow for so und loca lizati on, they do aid a pati ent to overcome the head shadow e ffect. CRO devices consist of essenti ally two hearing aids. One hearin g aid ac ts as a microphone in th e affected ear and transmits the auditory ignal to a second hearin g aid th at acts as a receiver in th e fun cti ona l ear. The C ROS hearing aid in current use are wire less devices th at u e FM or Bluetooth technology to transmit th e auditory signal to th e extern al rece iver.2

10

BAHA devices take advantage of the ph ys ical property of bone to conduct ound . The first BAHA device was developed by a Swedi sh anatomi st, Per-ln gvar Branemark, and impl anted in three pati ents in 1977. The dev ice has achieved international recognition as a solutio n to conducti ve hearing loss w ith more than 80 000 device currentl y in use worldw ide 6 The device also has a second applicati on fo r th e treatment of unilatera l sensorineura l hearing loss. 5 The BAHA system consists of three components: a titanium post implant, an external abutment and an e lectronic sound processor. It is important to note th at th e BA HA ystem requires surgical implantati on of the titanium post fo ll owed by th e integration of the implant into th e bony architecture. The device wo rks by transmitting sound thro ugh bone to the inner ear thus, skipping both the external In the case of unil ateral auditory canal and the middle ear.2·5 sensorineural hearin g loss the sound is transmitted transcraniall y and stimulates th e cochlear fluid of the unaffected inner ear. The titanium screw is implanted directl y into th e masto id bone in order to overcome th e lo s o f energy during the transcutaneous transmi ssion of sound . The electronic so und processor is responsible for the transmi sion of ound vibrati ons via the externa l abutment to the titanium implant. 7 Despite its value and populari ty, there are a number o f complicati ons a sociated w ith th e BAHA device. The most common complicati on is skin irritation at the site of the implant. 7•8 In most ca e , thi s can be managed using topical therapy. A more seri ous complication is the failure of th e titanium post to osseointegrate.7•8 Thi complicati on can lead to poor function or failure of the implant. In addition, several less common but potentiall y dangerous compli cati ons such as kin flap necrosis, wound dehi scence, bleeding and pain have been reported 8 The so und conducti on property of bone ex plo ited in the BAHA technology has also been applied in the most recent technological adva ncement for the treatment o f unilatera l sensorineural hearin g lo ; the SoundBite Hearin g Aid . THE SOUNDBITE HEAR ING AID

A unique technologica l approach for the treatment of unilateral sen orin eural hearing loss is the use of a removable ora l device called the SoundBite hearin g system developed by Sonitus Medica l. The SoundBite hearing system also makes u e of the ound conducti on properti es o f bone; yet, unlike th e BAHA system does not require the use of surgery.3•9 The SoundBite hearing system uses a mi croph one unit housing a receive r and wire less transmitter to receive so und . The mi crophone portion of th e unit its in the affected ear canal to take advantage of the ability of the ear 's pinna and ext~rnal ear canal to capture and direct sound into the microphone, whil e the rece1ver and the transmitter sit in a unit behind the affected 3 9 ear • The unit then transmits the captured ound wirelessly to a

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remova ble oral device similar to a retainer th at sits over the max illary mo lars in th e mouth. The oral device touches several stru ctures in the mouth including the gi ng iva, teeth and the inner cheek. The electri cal signal from the behind the ear transmitter i captured by th e ora l device and is transduced into vibrati onal energy usi ng a piezoelectri c transducer.9 The vibrati on are conducted by way of the teeth to the bone and transcrani a lly to the cochlea of th e ear. One of the adva ntage of the piezoe lectri c transd ucer is that it allows a much wider frequency range to be conducted thro ugh the teeth than the traditional e lectrodynami c transducers used in th e BAHA systems.9 The oral dev ice does not require th e mod ifi cati on of th e max illary mo lars and i custom fitted for each pati ent by taki ng a denta l imprint of the max illary arc h.3 Si nce th e device vibrate the max illary molars to trans mit v ibrat ions to the bone, the fo rce of the ora l dev ice wa te ted to detem1ine if it wea rs th e teeth . Interesting ly, the force of the oral dev ice is four ord ers of magnitude lower than the force exerted on the teeth by nonna l masti cation and is w ithin the force range of nom1al orth odontic devices and does not damage the surface of the max ill ary mo lars.9 Moreover, the ora l device is comfortabl e, we ll to lerated in most pat ients, does not affect the speech and can even be worn whi le eating.3路9 There are several adva ntages of th e SoundBite hearin g system which are outlined in Box l . The most strikin g advantage of the SoundBite hearing sy tem when compared to bone anchored hearing aid (BAHA) i the avo idance of surgery 9 A patient can be fitted qui ckly for th e oral device and begin using th e hearing aid immediately. With BAHA , The surgery is surgery is required to imp lant a titanium post. followed by 3 months of healing to ensure osseointegrati on of the The implant before th e pati ent can begin to use th e device 2 SoundBite hearin g system avo ids this dela y and avo ids potenti al The surgical complications seen with th e BAHA procedure. SoundBite hear ing y tem is a tru ly unique and nove l technologica l approach to address unilateral sensorineural hearing loss. The next time you ee a patient with unil ateral sensorin eural hearing loss, take a look in th eir mouth and chew on thi s possibility; they mi ght be li stening through their teeth!

Box 1: Advantages and Disadvantages of the Sound Bite Hearing System Advantages

Avo idance of surgery and su rg ica l complications No need t o wait 3 month s befo re use since osseointegration is not required Di screet oral device and discreet behind th e ear unit Opti mized microphone locati on Del ivers high-fidelity sound w ith a w ide f requency range Removab le devices Disadvantages

Cannot drink alcohol wh ile wearing the oral device Ri sk of aspiration of the ora l device if the patient' s physical responses are impaired Risk of swallowing the oral device if the patient's physical respon ses are impa ired Healthy teeth are needed to fit the device properly and good oral anatomy for full benefit; the last 3 teeth in the maxillary arch are usually the abutment teeth and must be free of active caries, periodontal and endodontic conditions

REFERENCES I . Woodcock K, Pole JD. Heal th profile of deaf Canadians: ana lys is of the Canada Commun ity Hea lth Survey. Can Fam Physician 2007 ;53( 12) : 2 140- 1. 2. Kim HH , Barrs OM . Hea rin g a id s : a rev iew of what's new. Otolaryngology-Head and Neck Surgery 2006; 134 : I 043-50. 3. Miller RJ . It's time we listened to our teeth : The So undBite hearing system . Ameri ca! Journal of Orthodontics and Dentofac ial Orthopedics 20 I 0; 138(5):666-9. 4. Sajj adi H, Papare ll a MM. Meniere's di sease. Lancet 2008 A ug 2;372(9636): 406-14. 5. Bishop CE, Eby TL. Th e current statu s of audi ologic rehabi litation for profo und unil atera l sensorin eura l hea ring loss. Th e Laryngosco pe 2009; 120:552-6. 6. Mudry A, Tjellstrom A . Hi stori cal background of bone conducti on hearin g devices and bone conducti on hearing a id s. Adv Oto rhin olaryngo l 20 11 ;7 1: 1-9. 7. Kraai T, Brown C, Neeff M, Fisher K. Compli catio ns of bo ne-anchored hearing aids in pediatri c patients. lnt J Pedi atr Otorhinolaryngol 20 II Apr 8. Wazen JJ, Young DL, Farrugia MC, Chandrasekhar SS, Ghossaini SN, Borik J, Soneru C, Spitzer JB. Successes and compli cati ons of th e Baha system. Otol Neurotol 2008 Dec;29(8): 1115-9. 9. Pope lka GR, Derebery J, Blevins N H, Murray M, Moore BC, Sweetow RW, Wu B, Katsis M. Preliminary eva luation of a novel bo ne-conduction device for single-s ided deafness. Otology & Neurotology 20 I 0;3 1(3): 492-7.

References (3 ,9)

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Falling on deaf ears: overview of cochlear implantation issues in Canada and locally Niran Argintaru (Med icine 2014), Moska Ham idi (M edic ine 2013) and Laura Allen (Medicine 2013) Faculty Reviewe r: Dr. Sum it K Agrawal MD

I

s de. afness a disease? Is it even a disability? Can or should it be "cured"?

Such questions have been the root of many debates ove r the nature of deaf c ulture since the advent of cochl ear implantati on in the late 1950s. As implants become more re liab le and provide increasing quality of hea ring to profound ly deaf childre n and adults, many in the deaf co mmunity have grown to view implantati on as a threat to both the ir way of life and the integrity of the communi ty. As a res ult, factions of deaf society have waged a war aga inst cochlea r impl ants. " I would be remiss not to eq uate cochl ea r implants with genocide" stated a 1992 deaf position arti c le. 1 While suc h quotati ons represent an extrem i t view in the communi ty, widespread concern s that coc hl ear imp lantati on would diminish the deaf co mmuni ty 's size and cohesiveness, and that cochl ear impl antati on represents a desire by th e hearin g popul ation to " cu re" deafness exi ted we ll into the 1990 .2 M any in th e deaf community fear that coc hl ear implants would res ult in decreased resource ava il ab il ty and acco mm odations for the deaf, and hence pose a threat to deaf culture. For the purpose of this artic le, deaf culture ca n be characteri zed as a co mmuni ty largely composed of pro fo undl y deaf indi viduals that views deafness as a difference rathe r th a n a disability 2 They characteri ze lack of hearin g as "deafhood" rather than "deafness", with so me in th e co mmuni ty going as far as ca lling deafness a " birthri ght of si le nce". 3 This comm unity provides reso urces, ed ucation and training to its deaf members, a llowing them to function within th e deaf co mmunity (i.e. through sig n language) and in th e hea rin g world (i.e. throug h lip read ing). If one were to co nsider implantation to be a treatment for profound deafness, most of those impl anted at a yo un g age are like ly to not partake in th e deaf communi ty as th ey wo uld now be integrated into ma instrea m edu cati on.4 As ev ide nce mo unts in favour of coc hlea r impl antat ion, a shift has been see n to a po int where th e vast majority o r e lig ib le c hi ldren are implanted, parti cularly if born to hearing parents. In response to th e grow ing prevalence of impl antati on, in 2007, th e Ca nadi an Association of th e Deaf (CA D) re leased a positio n paper o n coc hlea r implantation . They asserted th at whi le the CA D has litt le co ncern abo ut autono mous adult imp lantati on, they do not be lieve emp iri ca l research has provided suffi c ient evidence for the effi cacy of cochlea r implants in supporting first-language acqui s iti on in deaf chi ldre n, who a re un abl e to ma ke the cho ice for themse lves. 5 As th e body of scientific literature in the field overwh e lmin g ly supports early chi ldh ood imp la ntat ion, the CAD 's pos iti on appea rs to foc us on th e ri ght of every deaf child to lea rn sign language, regard less of whether th ey received an impla nt, allowing th em to grow up " bil ing ual and bicultura l". It is diffi cult however to assert w hethe r thi s po iti on

12

refl ects an effort by the CAD to mitigate th e loss of deaf cu lture by trying to increase the involvement of implanted children in the deaf communi ty.

THE RI GHT TO CHOOSE: WHEN TO I MPLANT? With new born hearing screening program offered in eight provinces an d three territo ri es as of 2008 , childre n with s ig nifica nt hearing deficiencies are identifi ed earli er than eve r6 Therefore, armed with an early diagnosis, parents are dri ven to mak e a decision regarding cochl ear implantatio n in e ligible c hildren earli er in th e c hild 's life, with a n increasing body of evidence indi cating s ig nifi cant advantages to earl y im pl antation . otabl y, implantation in childre n under two yea r o ld has been ex tensive ly show n to provide s ignificant improvement in language perception and vocabul ary, often allowing recipients to e nter first grade wi th lang uage ski ll s com parable to children with norma l hea rin g.7.8 Rece nt evidence indi catin g that impl antat ion as early as ix month o ld lead to better long-term impro vements in language, socia l ski ll develo pment and s ignificant adva ntages in parent-child bonding, has resulted in so me centres implanting infa nts even earlier. 9 While the current guide lines advise imp lantat io n at aro und two years o ld, studi es have shown little additi ona l ri sk of implanting pati ents at a signifi cantl y younger age, hence further shi ft ing the trend towa rd s ea rli er implantation. Is thi s trend towards earl y imp lantati on signifi ca nt in te nns of informed con ent? The ma in decisio n to implant has shifted away fro m th e pati ent w hen ea rl y chi ldhood impl antatio n tarted becoming co mm on. This has left parents w ith the full res pons ibility of choosing implantati o n as we ll as the degree of deaf educa ti on the child will receive if implanted . However, with children implanted earl ier, parents are faced with shorter timelines during which to educate themse lves abo ut the proced ure. Therefore, while implanting at six months ve rsus two yea rs does not s ig nifi ca nt ly a lte r the child 's abi li ty to co ntribute to th e decision, it may decrease the amount of tim e th e parents have to co n ide r th e c ho ice and co uld arguably pre ure pa rents into ras h decisions.

FUN DI NG OF COC HLEAR IMPLANTS lN AD ULTS AND PEDIATRIC POPULATIONS C urrent ly, three .centers (To ronto, London and Ottawa) provide the over 190 coc hlear implant surgeries perfo rmed a nnua ll y in O ntario. With wait tim es for imp la ntation surgery fa r above the recomme nded three months for ped iatric popu lation and six mo nths for adu lts 10 th e Ontario government re leased an additiona l $5.9 mi ll ion i i~ fun?ing in .March ~0 11 to cut wait tim es in ha lf. 11 Un fortunate ly, it is unlike ly thi s one-time fu nding package w ill address wai tl ist is ues in the long-run, partic ul arly in the time-se nsitive imp lantation of c hi ldre n as discussed above. Specifica ll y in London, a s ingle annua l budget is provided for

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both pedi atri c and adult impl antations. There are several problems th at arise from this fundin g mode l. Firstl y, as implant costs are covered under prov inc ial hea lth fund ing, patients cannot pu rchase their own implants in acco rd ance w ith the Canada Health Act. Secondl y, since a lump sum is all ocated to the fundin g of impl ants per hospita l, impl antati on can be undertaken onl y until the sum is ex hausted in a g ive n fi sca l yea r. La tl y, due to the ev idence presented above fo r ea rl y pedi atric implantati on, in fa nts must be im planted w ith in a certai n w indow of time after the di agnos is. Therefore, as more pediatric implants are perfo rm ed, ad ult patie nt are pushed bac k on the wai t-li st fo r th eir implants. However, this fundin g mode l does empower the hea lthcare prov ider in the audi ology tea m to eva luate patients and ass ign the fundin g to those th ey determine require it most.

UNILATERAL VS BILATERAL IMPLATATION T he Canadian Association of Speech- Language Path ologi ts and A ud iologist (CASLPA) pu bli shed th eir official posi tio n in th e Journ al of Otolaryngo logy supporting bilateral cochl ear im plantati on in all eli gib le children. Bilateral impl antations prov ide adva ntages in so und loca liza ti on, speech isolat ion in no isy conditions and improved deve lopment of the auditory system with few additi onal ri sks. Additi ona ll y, by implanting both ears, the " better ear" (the ear th at w ill fu ncti on better w ith th e impl ant) is always impl anted , maxi mi zing benefits fo r th e pati ent. 12 Hence, fo r the most part, e ligible Canadi an child ren who rece ive impl antati o n undergo simultaneo us bi lateral implantatio n as studies have shown no advantage to implanti ng the second ear on a later date, particul arl y at an older age. 13 While pedi atri c implantati on has been shown to be cost effecti ve by several tudies 14, th e cost effecti ve ness of providing bilatera l implantati on has been questi oned due to th e use of publi c fundin g of th e impl ants. A systemic review done in th e U nited Kin gdom comprised of 33 tri als, including two rand omi zed control tr ials showed a fa r higher cost effective qua li ty-adj usted li fe -yea r returns fo r unilateral im plantati on versus th e bilateral implantation in pedi atri c and adult populati ons. 15 With mounting evidence and strong recommendat ions in favo ur of bilate ra l implantati on, why is the cost effecti veness of th e second im plant much lower than th at of th e first? Firstl y, th e qu ali ty of li fe meas ures used to gauge improvements fo llowing the second implant are much more un certa in and inaccurate, as Bond 's 2009 rev iew ac knowledgesl 5 For example, it is diffi cult to measure the improvement in quality of li fe ga ined fro m increased abi li ty to loca lize so und or isolate speech. Secondl y, w ith the ability of a unilateral impl ant to allow child ren to attend mainstream school and often requ irin g almost no specifi c educati onal assistance, the maj ori ty of savings are rea li zed w ith th e first implant and are hence not refl ected in the additi on o f a second impl ant. Most significantl y, the incremental improvement fro m hav ing nearl y no hearin g to considerabl e hearing ac hi eved w ith a unilatera l impl ant is bound to be considerably higher th an the improvement achieved w ith the second implant.

Desp ite the effectiveness of imp lants, it is important not to di count the services and supports the deaf commu nity provides to its me mbers. Imp lantat ion i not a cure; rather, it i a upport ive treatment tha t along wit h consi derable training allows for increased fu nct ionin g. T herefo re, th ose im planted may sti ll find they can bene fit fro m partici pat ion in th e deaf co mmuni ty through support and sign language trai nin g.

REFERENCES I. Si lver, A. Cochlear Impl ant: Surefire prescription for long-term di sease. TBC News. 1992 ;53:4-5 . 2. Balkany, T., Hodges, A. V. , & Goodman, K. W. Ethics of Cochlear Imp lan tat ion in Young Chi ldren. Otolaryngo logy Head and eck Surgery. 1996; 11 4(7):748-55. 3. Ladd, P. Understandi ng Deaf Cul ture: In sea rch of Dea fh ood. Bristol: Mul ti lingual Matters; 2003. 4. Aronson , J. (Director). Sound and Fury [Motion Picture] ;2000. 5. The Canadian Association of the Deaf. Cochlear Imp lants [Internet] ; 2007 May 26 [Cited 20 11 March 23]. Avai lable from: http://www.cad .ca/ each lear_ implants%20.php. 6. Adams, J. Nationa l ewbom Screening and Genetics Resource Cen ter. Retrieved from Canadian Organization fo r Rare disorders; 2008 July 9. Ava il ab le from http://genes-rus. uthscsa.edu/CA_ nbsdisorder .pdf. 7. Kra l, A ., & O'Donoghue, G. M. Profo un d Deafness in Childhood . New England Jou rn al of Medici ne. 20 I 0;363( 15) : 1438-50. 8. Jvirsky, M. A. , Teoh, S. W., & Neuburge r, H. Development of Langugage and Speech Perception in Congenitally Deaf Children as a Function of Age at Coch lear Implantation . Audiology and neurooto laryngology. 2004 ;9( 4 ):224-33 . 9. Cosetti, M. , & Roland, T. J. Coch lear Implan tation in the Very Young Chi ld : Iss ues Un ique to the Under- ! Popu lation. Trends in Ampl ification. 2010; 14( 1):46-57. I 0. Canad ian Assoc iation of Speech-La nguage Patho logists and Audio logists: Recomm ended Wa it Tim es [Intern et]. Speach and Heari ng; 20 II [Cited 20 II Ma rch 23 ]. Avai lab le from: http -ljwww speec handh eari ng ca/en/ find-a-professional /wait-time-recommendations?start=l 0 I I. Morrison , A. New room Ontario: Improving Access To Devices For People With Severe Hearing Loss [Internet]. [Cited 20 II March 15] Avai lab le from : htt p://new s.ontario .ca/mohl tc/en/20 11 /03/ improvingaccess-to-dev ices-fo r-peop le-wi th-severe-hearing -loss. htm I 12. Schramm, D. Canadian Po ition State ment on Bi latera l Cochlear Im plantati on . Jou rn a l of Oto laryngo logy Head & Neck Surge ry. 20 I 0;39(5):4 79-85 . 13. Graham J, V. D. Bil atera l sequentia l cochl ear imp lantation in the congenita ll y deaf child : evidence to support the concept of a 'critica l age' after whi ch the second ear is less likely to provide an adeq uate level of peech perception on its own. Cochlear Implants Int. 2009; I 0(3): 11 9-4 1. 14 . O'Nei ll , C. , O' Donoghue, G . M., Archbo ld, S. M., & armand, C . (2000). A Cost-Ut ili ty Ana lysis of Pediatric Cochlear Imp lantation . T he Laryngoscope. 2000; II 0( I): 156-60. 15 . Bond M, M. S. The effecti venes and cost-effecti veness of cochl ear im pl ants fo r severe to profo und deafness in children and ad ul ts: a systematic review and economic mode l. Hea lth Techno! Assess. 2009 Sep; 13( 44): 1-330.

CONCLUSIONS By many accounts, th ose who argue th at cochl ear impl antati on is un ethi cal , ineffecti ve or simpl y not the best choice fo r profo undl y deaf children appear to have been unsuccessful in preventing th eir w idespread use. However, as impl antati on shifts fro m being a novelty to the norm , th e issues of fundin g and cost efficiency appear to have taken centre stage in Canada, and parti cul arl y in Ontari o. With earl y bilateral implantation established as the best th erapy for profo undl y deaf children, fu nding must be ava ilable to implant a ll eligible children whose parents choose impl antati on. If such fundin g is not available, as seen in some centres, wait lists w ill persist and grow parti cularl y in adults as pedi atri c pati ents are g iven pri ori ty.

UWOMJ I 80 :21 Fall2011

13


"Is Beauty Truly in the Eye of the Beholder?" The Universal Nature of Facial Beauty Michal Brichacek (Meds 2013), Robert Moreland (Meds 2013) Faculty Reviewer: Dr. DamirMatic, MD MSc FRCSC, Plastic Surgery

ur face allows us to convey o ur every tho ught and feeling with those aro und us in a nea rl y instantaneous mann er. Without our face, we wo uld be stuck in an e mot ion less a nd depre si ng se lf-ex iste nce devo id of a prim a ry ve hi c le of com municati o n. As soc ial beings, it is in our very nature to sha re our ex pre ion with the o ut ide wo rld . It i likewise in ou r nature to subconsciously j udge each face, ass ignin g certai n traits to parti cul ar facial characteri tics. One of th e most impo rtan t characte ri sti cs th at we judge is " beauty". Interestin gly, th ere is an unusually consistent agreement of what is con idered " beautiful " a mongst different cultures, but onl y when we are referring to the face rath er than the body, a topic that wi ll be ex plored herein .

0

BEAUTY OF THE BODY So what is it th at makes a perso n " bea utiful"? Bea uty is an arbitrary and abst ract concept that is seemin gly difficu lt, if not impossi bl e to define. Considerin g th e vast di ve rsity in thi s world and the countless cultures it conta ins, one would expect that surely th ere must be di ffe rent culturall y dependent standards of beauty. Howeve r, research suggests that this is o nl y parti all y correct. Research examining the ph ys ica l attracti veness of the fema le body often uses the wa ist-to- hip rati o (WHR) as a qua ntifiabl e meas ure. Indeed, studi es ha ve found th at males from most cultures a nd across history stron gly prefe r female figures with a low WHR .,ln the developed world, hea lthy females have hi gher leve ls of estroge n that ca use more fat to be deposited o n the buttocks and hips rath e r than on th e wa ist, leading to a low WHR.Thus, th e WHR is an indicator of health status and ferti li ty, and male pre ference for lowWHR females is conside red an excell ent exampl e o f ma le assess me nt of mate quality3

Matsigenka indi ge nous peo pl e in Peru, who are located in an ex ten ive nature pa rk where access is restri cted solely to scientific and offic ial visito rs and the vast majo ri ty of nati ves have never left th e prem ises .3Their results showed that the WHR preferences of ma les of thi s tribe di ffe red strikingly from those of the United States control population as we ll a from othe r world c ulture , with the " over-weight" female ranking hi g hest in the factors of attractiveness, hea lthiness, and prefe rred pouse.3 The e were criti cal finding a they di ffe red striking ly from the pre ferences of ma les in other cultures. The authors suggest that this difference may be du e to the fact that in traditi o na l societies, physical featu res may play a lesser role because mate c hoi ce is limited by kinship rul es, an d potenti al mate have access to direct info rmation about mate qu ali ty, suc h as age a nd history of illness.As a result, th ey do not rely primarily o n information infe rred from physica l appea rance . In contrast, in industrialized societi es, daily ex posure to strangers from an early age may increa e the impo rtance of u ing ph ys ica l featu res to assess potential mates based o n th ese factors .3 FACIAL BEAUTY It seems reaso nab le to que ti o n > hethe r th e e relati ve cultural norms likewi e influence our perceptio n of facial bea uty.Counterintuitivel y, the answer is no. Be fo re ex ploring thi s to pi c, we must first consider what exactl y facia l bea uty is and how to define it. The quest to find to suitable defi nition of fac ial bea uty date back to antiquity, when th e ancient Greeks be lieved th at beauty appeared when the ratio of many di ffe re nt facial features to each other approached the va lue I : 1.6 18, the o ca lled golden ratio. However, things are not so simple, as furth er research has shown that facia l bea uty i more a combinati o n of symmetry and a n idea l harn1ony of the facia l features with each othe r. And mo t importa ntl y, as huma ns we have an innate mec ha ni sm fo r detecting this elusive concept of beauty.

Despite th e ove rall prefere nce of men for wo men with a low WHR, variations do ex ist, th ere by casting do ubt on the theo ry th at thi s may be a uni versal idea l. Anoth er meas ure of body habitus is th e body mass index (BM !), whi ch is a he uri sti c proxy for human body fat. Different cultures a nd popul ati ons prefer females of differe nt BMI and WHR du e to different sociocultura l influe nce . Undeniably, th e effect of " Westerni za ti on" may be contributing to a more universal stand ard o f bea uty, but thi is not due to our innate evolutio nary preferences. Rega rdl ess of th ese influences, a study comparin g fema le phy ica l attracti ve ne between Japanese and British parti cipants found that Japanese men preferred images of wo ma n with signifi cantl y lower BM! s th an Britons and likewi e we re mo re re li a nt o n bod y s hape when judging ph y ica l attractiveness.

.T he re are several exa mple that seem to re inforce this concept. For Insta nce, superm odels, arguab ly con idered the mo t attractive membe rs of We tern ociety, have the least degree of facial asymmetry when compared to the ge ne ral population . Facial a ymmetry ex ists a long a gradi e nt in our population and it is clear th at we have evo lved to tol erate some deg ree of thi asym metry.

However, th e fl aw with th ese studi es in general is th at every culture tested so far has been ex posed to th e potentially confoundin g influence of Western media . A la ndmark study by Yu and Shepard assessed the WHR preferences of a c ulturall y iso lated populatio n of

Interesting ! ~, studi es ha~e shown that averag ing a random group of. faces res ults 111 a synthet1 c face more attrac ti ve than a ny of the o n g mal faces .,The faces used in these a na lyses consisted of thirtytwo completely random faces from a pool of diffe rent c ul ture , yet

14

Symmetry is an impo rtant a pect of facia l bea uty and i tied to evo luti onary fitn ess, where le ft-ri ght bilateral symmetry describes hea lth a nd hi gh geneti c quality, and devi ations from it may indicate poor qu alities and there fore form a basis for rej ection of a potential mate.,

UWOMJ I 80:21 Fall2011


observers always ranked the composite face as be ing the most attractive. Paradox ica ll y, th i suggest that the idea l ham1ony of the fac ial featu res that we consider to be " beautiful " is actua ll y as close to "average" as pos ible. Naturall y, such statements have draw n criticism from many indi vidua ls who refu se to be li eve that beauty may in any way related to "ave rage ness". It is critical to note that the com putatio na l "average" of fac ial features that is considered attractive in thi s case is completely disti nct fro m w hat cul ture commonl y refers to as an "average" fa ce, whi ch natura ll y has a nega ti ve connotati on and is not co nside red " beautiful ". There are certa inly unique and interestin g fea tures that may add to the perce ived attractiveness of an indi vidua l's face, but it is important to realize that they must be associated with an "average" face and must be harmonio us with the other faci al fea tures. Th ere have bee n a rg u me nts th at bea uty is a c ul tura l phenomenon engrained in us repeatedl y th ro ughout our yo uth, resul ting in a bia ed preference such as that of male for fe males with a low WHR ratio . However, there are many exam ples that d isprove this theory. Eleven separate meta-ana lyse have revea led very hi gh agreement in fac ial-attracti veness ratings by raters both within their own cul tu re, and across other culture ., In fact, the effect sizes we re more than double the size necessary to be considered large and thereby strongly suggest a uni ve rsal sta ndard by whi ch fac ial attractiveness is j udged. ln order to negate the possible influence of Western media, a stud y examin ing preferences fo r fac ia l symm etry betwee n Briti sh individuals and the Hazda, a hunter-gatherer soc iety of Tanzania, li kew ise fo und that facia l symmetry was more attracti ve than asymmetry across both cultures. These findin gs fu rther question the ass umpti on that ratin gs of facial attracti veness and ideals o f fac ial " beauty" are culturall y unique and are consistent with the fac t that young infa nts prefer to look at face that adults likew i e consider to be attractive. It is im portant to realize that there are exogenous fac tors that augment attracti veness and beauty as it pertains to mate selection, whi ch is prec isely why it i such an elusive concept to defin e. Dutton argues that based on Darw ini an aestheti cs, indi vidua ls consciously select mates who have certa in characteristics, and that such characteri stics in fac t may make the person more attracti ve and " beautiful " to them. Dutton furth er states that it is human personali ty that adds another dimension of beauty, with traits such as a delightful sense of humor and generosity being attractive. ! ? Although it is still evoluti onaril y based on fi nding a healthy mate who is able to provide care, it is thi s rationa l intention combined with physica l appearance that forms a complete v iew of beauty and attracti veness.

CONCLUSION Beauty is an elusive concept that is envied and sought by many, yet is extremely difficult to defin e.Aithough the beauty of the body has an evolutionary basis, the concept of the ideal body is a cultural construct that has been influenced and continues to be influenced by culture and media. Conversely, fac ial beauty is a biologicall y ingrained concept based on symmetry and an idea l coalescence of that fac ial features with each other that transcend barri ers of culture, media, and time. Ultimately, concepts of beauty and attracti veness are evoluti onaril y based, but cannot be looked at narrowl y as based so lely on appearance as they are augmented by exogenous fac tors.

REFERENCES I. Singh, D. Hum. Nature 1995;6:5 1--68. 2. Fumham, A., Tan, T. & McManus, C. Pers. lndi v. Di ff. 1997;22 :539- 549. 3. Yu DW, Shepard GH. " Is beauty in the eye of the beholder? Nature 1998 ;396:32 1-322. 4. Swami V, Caprari o C, Tovee MJ, Fumh am A. Female Phys ical Attracti veness in Britain and Japan: A Cross-Cultural Study. European Journal of Personality. 2006;20:69-8 1.

5. Atalay, B. (2006). Math and the Mona Lisa: The art and science of Leonardo da Vin ci. New Yo rk , NY: Harper Colli ns Pu blis hers. 6. Steve n , M.; Castor-Perry, S.A.; Price, J.R.F. The protective va lue of conspicuous signals i not impaired by shape, ize, or po ition a ymmetry. Behav. Eco l. 2008;20:96-1 02 . 7. Jones, B. C., Little, A. C., Penton-Voa k, I. S., Tiddeman, B. P., Burt, D. M., &Perrett, D. I. (2 00 I). Facial ymm etry and j udge ments of apparant health support fo r a "good genes" ex planation of th e attracti venes symmetry relati onship.Evolution and Human Behavior, 22 , 4 17-429. 8. Za idel, D. W. ; Deblieck, C. Attracti veness of natu ra l faces com pared to computer constructed perfec tly sy mmetri ca l faces. lnt. J. Ne uro ci. 2007, 11 7, 423-43 1. 9. Langlois, J. H., &Roggman, L. A. ( 1990). Attracti ve faces are onl y average. Psychologica l Science, I(3 ), 115- 12 1. I 0. Rh odes, G., & Jeffery, L. (2006). Adapti ve norm -based coding of fac ial identity. Vision Resea rch, 46( 18), 2977- 2987. II . Langlois J H, Kalaka ni s L E, Rubenstein A J, Larson A D, Hall am M J, Smoot M T, 2000 "Max ims and myths of bea uty: A meta-analyti c and theoreti cal review" Psychologica l Bu lletin 126 390-423 12. Langlois et al. "Max ims or Myt hs of Bea uty? A Meta-A nalyt ic and Theore ti cal Review". Psychological Bu lletin . 2000; 126:390-423. 13. Co hen, J. ( 1988). tati sti ca l power analys is for the behav ioral sciences. Hftl sdale, NJ: Erlbaum . 14. Little AC, Apicella CL, Marlowe FW. Preferences for symmetry in human faces in tv;o culture : data fro m th e UK and the Hadza, an isolated group of hunter-gath erers. Proc. R. Soc. B 2007;274 :3 11 3-7. 15. Rubenstein A J, Langlois J H, Roggman L, 200 I "Wh at makes a face attracti ve and why?", in Facia l Att ractiveness: Evo lu ti onary, Cognit ive and Social Perspective vo lume I of Ad va nce in Vi sual Cogniti on Eds G RJ1odes, LA Zebrowitz (Westport , CT: Ablex Publishing) fo rth- co mi ng 16. Dutton, D. (2 009). The Art Instinct: Beauty, Pleas ure, and Hu man Evoluti on. New York, NY: Bloo msbu ry Press.

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15


Incidence of acute respiratory distress syndrome and acute lung injury in patients requiring prolonged mechanical ventilation Paul Kudlow, B.Sc. (Meds 2013), Chu L, B.Sc, Herridge MS, M .D., M.P.H Faculty Reviewer: Nigel Paterson, M .D.

rim aril y affect ing criti cal care pati ents, Acute Lung Injury (ALI) and its more severe variant, Acute Respiratory Di stress Synd ro me (A RDS ) a re devastatin g clini ca l syndromes, h av in g l o n g- t e rm functional a nd neurop syc hol og ica l conseq uences I ,2,3. Further characterized by ac ute hypoxemia, bilateral pulmonary infiltrates on frontal chest radiogra ph y, and no clinical evidence of left atria l hypertension, AR.DS/ ALl are severe inflammatory conditio ns of the lung parenchyma4 ,5. The resulting severe hypoxemia combined with the ex ten sive release of systemic inflammatory medi ators often leads to multiple o rga n failure; responsible for hi gh rates of morbidity and mortality in the populati on6. Despite many recent advances in our understandin g of the pathoph ysio logy, trea tm ent, and long-term outcomes of ARDS/ ALI , in cide nce and preva le nce of these conditions remain s un certai n6. The un certainty in tum refle cts the heterogeneity of th e syndromes, the lack of de finitions for th e underl ying disease processes, and fa ilure to uniforml y defin e the population within which pati ents wi th AR DS/ALI are identified5 . The inci dence of ARDS/A LI in th e United States has been estimated to be around 300,000 ca es per yea r, but thi s may be an underestimate6. A recent study, conducted by Rubenfeld et al. examined th e gene ral ICU population and found the incidence of ARDS/ ALI to be somewhat hi ghe r, at app roxi mately 58.7 and 78 .9 per 100,000 respectively; giving an a nnual estimated incidence at around 141 ,500 and 190,600 cases of ARDS/A LI respecti ve ly in th e United States per year6.

P

RESULTS The study sample contai ned 82 pat ients . They had a median age 59 yea r , the male : female rati o was 1.4:1, and 45% of those sampled were found to have ~ 2 comorbidities. The median APACHE II core of wa 25 a nd a the median ICU LOS of was 37 days. In our study sample, 72% survived until ICU di charge. To date, the records of 25/82 pati ents have been examined (by both co-a utho rs) for the presence of ARDS/ALI. Of this sample, 2 1/25 (84% ) had radi ogra phic ev idence of bilateral infiltrates and fulfilled AECC criteri a for AR.DS/ALI. Interobserver variability, measured by kappa score, was 0.60 (Fig ure I).

DISCUSSION In thi s limited ample, there were a hi gh pro portion of patients who fulfilled the criteri a for ARDS/ALI. Although the re was insufficient data to acc urat ly calcul ate incide nce at present, our preliminary propo rti on of 84% , ugge t that the incidence of ARDS/ALI in tho e mec ha ni ca ll y ventilated for at least I week, likely exceeds 58.7 and 78 .9 per I 00,000 pe r o n- years respecti ve ly as previou ly de cribed by Rubenfe ld et al. in their ampl e of general ICU patients6. Our result were trengthened by relatively good agreement between independent e aluators; we measured a kappa score of 0.60 (Figure I ).

The purpo e of the current study was to dete rmin e th e incide nce of A RDS/A LI in a pilot sam pl e from a prospecti ve multi -centre follow-up of criti ca ll y ill pati e nts mechani ca ll y ve ntil ated for at lea t one week - the Towards RECOVE R stud y? . The incidence of A RDS/ A Ll in pati e nts requiring pro lo nged mec hani ca l ve ntilati o n is not kn own. We hypoth es ized th at th e incidence of AR.DS/ALI would exceed that found in ge neral ICU pati ents, as cited above.

METHODS

.

i

N

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0

• •

• •

..., "'c

As part of the Towards RECOVER study protocol?, pati ents were included if they were ~ 16 year o f age and mec hani ca lly ventil ated for at least one week . (n= 82) . Chest imag ing was performed dai ly for th e first ICU week and each Monday a nd Thursday th e rea fter. in vesti gators (PK, LC) unde rwent systemati c training on Chest XRay (CXR) inte rpretation for ARDS/ ALl by a standardi zed on line educational tutoria lS. CX Rs were divid ed into 4 qu adrants, each ana lyzed fo r th e pre ence or absence of bi late ral infiltrates consistent with non-cardi ogenic pulmonary edema. Diagnosis of ARDS/ALl was based on American Europea n Consensus Conference on AR.DS (AECC) guid elines. Data was ana lyzed to de tennine the percentage o f radiograph read inde pendently as ARDS/ ALI by each reader and interobserve r variability was be calcu lated (kappa-stat istic)9. All analyses were perform ed using appropriate so ftware.

16

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• • • 2

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Fig ure I. The area of the circ les is proportiona l to the number of subject give n a particu lar pair of ratings.

UWOMJ I 80 :2 I Fall 2011


Taken together, our preliminary result sugge t that ARDS/ALI are likely under recognized conditi ons, particul arl y in cri tically ill patients requiring pro longed mechani ca l ventilation. Earlier tudies have estimated the mortality due to A RD I A Ll at aro und 133,500 deaths per yea r in the Uni ted State 6. Give n the possible under recognition however, ARDS/ ALI are conditi ons likely responsibl e fo r even more deaths in the population. Besides mortali ty, ARDS/ ALI also leads to large amoun ts of costl y and often debi litating morb idity in urv iving pati ents and their caregiver I ,3,6. Outcome studi es have co ns i te ntl y fo und s ig ni fica nt fun c ti o na l a nd neuropsyc hological derangement at both I year and 5 yea rs po t illness \ ,2,3. Perhaps better identification of A R.DS/ALJ in the fi r t place may help to more efficientl y allocate hea lth care resources - in tum potentia lly preventing orne of the typica l long-term sequelae currently experi enced by surv ivo rs and their caregivers. Before making any fi rm conclusions however, it should be noted that although the results of our preliminaty study are suggesti ve of under recogni tion of AR.DS/A LI, they are subject to a number of important limitations. Particularl y, thi s stud y wa not onl y limited by ample ize, but also, data coll ected was subj ect to survi vorship, selection, and ascertainment biases. Additi onall y, analysi of data collected was limi ted by the level of training of the independent evaluator (PK, LC). The independent evaluators were trained using an online sta ndardized tu torial to a sist in the detennination of bilateral pulmonary infi ltrates as per AECC guideline 5,8. Although good agreement was measured benveen independent evaluators, the data remain to be fo rmall y evaluated by a trained phy ician. Therefore, larger fu ture studies are needed to va lidate and confi m1 the preliminary re ult of thi current tudy.

N arth Perth Family Health Team

Funding provided by the lnstiture of Medical Science. University of Toronto. CIHR, MOH Alternative Funding Plan - Innovation Fund. Acknowledgmenls: We thank Dr. George Tomlinson fo r his assistance with statistical analysis. As well, thank you to D1: Cathy Tansey, Andrea Malle, and Joel Elman fo r their assistance 111ith recruitment and data collection.

REFERENCES I. Herridge et al. "Functi onal Disa bi lity 5 yea rs after Acute Respiratory Distress yndrome." New England Journ al of Medi cine. 20 II ; 364: 1293- 1304 2. Hopkins et al. " europsychological equelae and Impaired Health tatu in Survivo rs of Severe Ac ute Respiratory Di stress Syndrome." Ameri can Journ al of Respiratory and Critical Care Medi cine., Volume 160, umber I, Ju ly 1999, 50-56 3. Herridge et at. "One Year Outco mes in urvivors of th e Acute Respiratory Distress Syndrome." New England Journal of Medi cine 2003 ; 348: 683-93 . 4. Ware et el. "The Acute Re pi ratory Distress Syndrome." New England Journ al of Medicine. 2000; 342: 1334- 1349 5. Berna rd et ai."The American Europea n onsensus Conferenceon ARDS. Defi niti on , mec hani sms, re leva nt out co me , and c lini ca l tri a l coordinati on." America n Journ al of Res piratory and Critical are Medi ci ne. 1994 Mar; 149 (3 Pt I): 818-24. 6. Rubenfeld et al. " Incidence and Outcomes of Acute Lung Inju ry." ew England Journal of Medi cine. 2005 ; 353 : 1685 -1 693 7. Herridge et al. ''Outcomes and Need Assessment in the Intensive are Unit (ICU) Surv ivors and Their aregivers (RECOV ER)'' Retrieved online April 17 20 II . http://clinicallrials.gov/ct2/show CT00896220? term=towards+recover&rank= I Hypothe is Wehypothesizeth anh eincidenc eo fA RDS/ A Ll exceeds58.7and78.9pe 8. Rubenfeld. "Improving the Radiographic Diagnosis of Acute Lung Inj ury" University of Wa hington. Retrieved online Apri l 17 20 II. http:// depts.was hington.edu/kclip/about.shtml 9. Ru benfeld et al. " lnterobserver Variab ili ty in Appl ying a Radi ographic Defi nition of ARDS" Chest. 1999; 11 6: 1347- 1353

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UWOMJ I 80 :2 I Fall 2011

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Shortness of breath in a 12 year-old boy: a classic presentation of stage IV Hodgkin's Disease? Michael Livingston (Meds 2011) Faculty Reviewer: Dr. Neil Merritt, M.D., FRCSC

hane is a 12 yea r-o ld boy who prese nts to yo ur offi ce w ith wo rsenin g shortness of breath o n exe rti on. Hi s fa the r ex plains that hi s son had severe asthm a when he was yo un ge r. He wa adm itted to hospital when he was 2 yea rs old and put on a vent ilator in th e intensive care un it when he was 4. Hi s symptoms have been much better since then. In fac t, Shane has n't had to use puffers very much at all up until a few month ago. He started u ing Ye ntoli n aga in while playi ng soccer and does get some relief with thi s.

S

IS IT ASTHMA ? Yo u take a thoro ugh history from Shane 's fath er. He notes that th e shortness of breath has come on gradu all y over th e last few month s to the point where it ca uses Sha ne diffi c ulties several times per week. There is no hi story of producti ve co ugh, and no fever, ni ght sweats or we ight loss. Shane has no oth er medi cal conditi ons, no know n allergies, no previous surgeri es, a nd his vaccinati ons are up to date. Hi parent are from Barbados but he ha never been out of th e co untry himself. Shane 's 13 year-old brother had a co ug h recentl y but there are no oth er sick contacts. O n examinat ion, Shane is a lea n-l ookin g child but otherwise appea rs we ll. Head circumference a nd height are above th e 50th percentile and we ight is above th e 25th percentile. He has no cerv ica l, suprac lav ic ul a r, infrac lav ic ul a r, ax ill a ry, o r ing uin a l lymphadenopathy. His respirato ry exam is significant fo r mild wheeze thro ugho ut but no crackl es or areas of decreased breath so unds. You ex pl ain th at Sbane's symptoms most like ly repre ent worsening asthm a. You give Sha ne a presc ripti o n fo r inhaled steroid and e nco urage him to use it tw ice per day. Yo u also give him a re fill for Vento!in and ex pl ain that he can use it wheneve r he fee ls sho rt o f breath . Shane's fath er agrees to foll ow- up with yo u in one month . IS IT INFECTIO US? Yo u see Shane and hi s fath er bac k in clinic one mo nth later. Hi s fath er looks very concern ed. The hortn ess o f breath co ntinues to be an issue and now Shane has a rash. The ras h sta rted be hind hi s kn ees and has spread to hi s trunk, a rms, and neck. The ras h is pruritic and both ers Shane quite regul arl y. Yo u do a full review o f systems a nd di scover tha n Shane has been feeling generall y un we ll recentl y. He repo rts no ni g ht weats, feve r, or we ight loss, and no pain at ni ght. Exa minati on o f th e ras h revea ls numero us crusted papu les meas uring 3-5 mm in di ameter (see Figure I). Hi s fath er assures yo u th at Shane has already had chi cke n pox. The ph ys ical examinati on is oth erwi se th e same as Shane 's prev ious visit. There is no lymphade nopath y and th e mild wheeze heard o n res piratory exam is un changed. You presc ribe hydrocorti sone c ream fo r th e ras h and set up an outpati ent re ferral to In fec ti o us Di sease.

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Figure 1. Crusted papules measurin g 3-5 mm consistent w ith pityriasis lichonoides [4). WHAT ELSE CO LD IT BE? hane is seen by yo ur co lleague in Infecti ous Di ease six weeks late r. hane has now deve loped a dry coug h. The ras h is till prese nt alth o ugh th e itc hine s i re lieved so mew hat by th e topi cal hydrocorti so ne. A rev iew o f syste ms reveal s th at Sha ne has now lost abo ut 5 pound since the wo rsenin g of sho rtn ess of breath began . hane deni es feve rs and ni g ht sweats, but hi s fath e r ays that, " he's bee n feeling rea ll y un we ll recentl y." Phys ical exa minati on reveals anteri or cervica l a nd suprac lav icul ar lymphade noa pthy. The nodes a re nontender, rubbery and range in size from 1 to 2. 5 e m . Respiratory exam is significant for w heeze but th ere are no crackl es or areas o f decreased breath so unds. Yo ur colleag ue ex pl ains th at he needs to get a c hest x-ray as part of hi s workup . He agrees th at Shane is quite sick a nd will need more te ts. He sends Shane to the Pediatri c Emergency Department for furth er eva luation . HOW BAD IS IT? Sha ne is as essed in th e Emergency Departm ent later that afternoon . He has a fever of 38 .5 degrees Celsiu s, tachycardi a with a heart rate o f I ~5 ~ and oxygen saturati o n of 94% on room air. The Emergency Ph ys1c1an o rders a chest x-ray (see Fig ure 2) a nd bloodwork. The chest x-ray reveals mass- like pulmonary opac ities in both lungs and enlargement o f th e hila and supe rior medi astinum . B loodwork is signifi cant fo r a white b lood cell count of 32.0

~hich con ist o f 24.0 ne utrophil s a nd 4 . 1 eosino phil s. H emoglobi~ IS decreased slightl y at 129. Platelets are ele vated at 55 1 C reacti ve protein is 111 .8, and erythrocyte sedimentation rate i '54. Lactate dehydrogenase is hi g h at 61 6 but urate and cal c ium a re normal.

UWOMJ I 80 :2 I Fall 2011


Figure 3. Compu ted tomography sca n of the thorax showi ng masses in the lungs and hil ar and medi stinallymphadenopathy. Figure 2. Chest x- ray of a 12 yea r-o ld boy, how ing a medi a tina] mass, hil ar enlargement, and patchy mass- like opacities in the lungs. Shane is admitted to hospital by the inpatient Ped iatrics team for further workup. The differentia l includes infection, va culiti , and ma li gnancy. He is placed on airborn e contact precauti ons and admitted to a negati ve pres ure room until tubercu losis can be rul ed out.

IS IT CANCER? Shane undergoe a CT scan of the pelvis, abdomen and th orax the following day (see Figure 3). The CT revea ls multiple solid nodules in both lungs, as well as mediastinal and hil ar lymphadenopath y. Enlarged nodes are seen in the para-ao rti c area but there are no signs of a primary tumor. General urgery in consulted to obta in a biopsy. Shane and hi s parents remai n anxious over the next few days as they wa it for a spot to open up in the operating room. In the meantime, Shane's white blood cell count remains in the hi gh 20s and pl ate lets rise up to 762 . Shane goes to the operatin g room three days afte r hi s admission for bi opsy of a superficial supraclav icular lymph node and skin under genera l anesthetic. Frozen section of the lymph node is pos iti ve for malignancy but fl ow cytometry is normal. A definite diagnosis is deferred until permanent sections can be processed. Over the next few days, Shane's shortness o f breath worsens. The vasc ulitic bloodwork comes back norma l and acid-fast cultures are negati ve for tuberc ulos is. The fin a l patho logy report i relea ed one week later indicatin g Hodgkin 's Di sease, Nodular Scleros ing subtype.

IS TIDS STORY TYPICAL FOR HODGKJN ' S DISEASE? Shane's story ma y seem somewhat convo luted but hi s symptoms are actually quite typical. In children, less than 20% of patients present with one of the classic " B" symptoms of Hodgkin 's Disease (weight loss, fe vers, and drenching night sweats) [ 1] . In fact, the most common presentation in children consists of painless cervical lymphadenopathy (which occurs in 70-80% of cases) and/or a mediastinal mass (in 50% of cases) [2] . Shane's initial chief complaint was shortness of breath due to the mass e ffect of mediastinal lymphadenopathy. This eventual ly progressed to a cough and hypoxia. The lesions in the lungs represent a combination o f

contiguous spread from hilar lym phadeno pathy and metastases to lung parenchyma [3]. The ras h and itchiness that Shane ex perienced isn' t that unusual either. In fact, some patients will give a hi story of insid ious itchiness for months before being diagnosed wi th Hodgkin 's Di sease [2] . The sk in les io ns in thi s case most li ke ly represented pityriasis lichenoide , which is a sociated with lymphoma [4]. Shane 's initial bl ood wo rk is classic fo r Hodgki n's Di sease. At first glance, the elevated white bl ood ce ll count consisting almost entirely of neutrophil s would seem to suggest an infectious etio logy. This is certa inly supported by the hi gh pl atelet count, C reacti ve prote in, and erythrocyte sedimentati on rate. (Indeed, in this case, Shane remai ned on airborn e contact precauti ons until tubercul osis was fonnall y rul ed out with a negative acid- fast bacilli culture.) Neverthe less, a compl ete blood count characteri zed by neutrophilia, eo inophili a and thrombocytos is is cia sic for Hodgkin 's Di sease in children, and is not du e to underl ying in fec ti on [I , 2, 5]. The presence of elevated lactate dehydrogenase would lead to some suspect tumor lysis syndrome. The elevated levels seen in thi s case ac tuall y represent a hemo lytic anemia, which is not un common in Hodgkin 's Di sease [6]. The norm al serum electrol ytes and urate leve ls seen here stand aga inst the presence of ongoing tumor lysis.

WHAT lS THE PROG NOS IS? Shane has stage NB Hodkin 's Di sease acco rding to the Ann Arbor Staging C lass ificati on [5]. He has diffuse invo lvement of I or more extral ymphati c organs (stage IV) and has 8 symptoms (B). Thi s places Shane in the hi gh-ri sk category [5, 7]. Even so, with proper treatment and monitoring the 5-year survi va l for children like Shane is up to 90% [7 , 8]. Shane was started on induction therapy whil e in hospita l, consisting of cyc lophosphamide, v incri stine (Oncovin), procarbazine, and prednisone (COPP). He was di scharged home once hi s breathing improved and will complete three more courses of treatment be fore rece iving radiati on therapy.

UWOMJ I 80:2 I Fall 2011

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REFERENCES I. Gottschalk SM, McClain KL (20 I 0) Overview of Hod kin lymphoma in children and adolescents. UpTo Date. www uptodate com. 2. Hay WW, Levin MJ , Sondheimer JM , Deterdin g RR (2009). C urrent Diag no is a nd Treatm ent Pedi atri cs, 19th Ed. Th e McG raw - Hill Companies, Inc. : New York . 3. Andreoli TE, Carpenter CCJ, Griggs RC, Losca lzo J (2007). Ceci l E enti als of Medicine, 7th Ed. Sa unde rs : Phil adel phi a. 4. Klein PA (20 I 0). Pi tri a i s Lichenoides. eMedicine . emedicine.medscape.com. 5. Kliegman RM , Marcdante KJ , Jenson HB , Behrman R.E (2006). el on E en ti a! of Pediatrics, 5th Ed. El evier aunders: Philadelphia. 6. McMillan JA , Feigin RD. DeAnge li C, Jones MD (2006). 0 ki' Pediatrics. Principles and Practice, 4th Ed. Lippincott, Williams & Wilkins: Philadelphia. 7. Schwartz C L (2005). Special issues in pediatric Hodgkin 's di ease. Eu ropean Journal of Hemato logy uppl e ment 66: 55 . 8. Foltz, LM , Song, K W, onn ors, JM (2006). Hodgkin's lymph oma in adol e cents. Journal of C lini ca l Oncology 24:2520.

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UWOMJ I 80 :21 Fall2011

Schulich MEDICINE & DENTISTRY


Obstructive sleep apnea in children: the when, how and why of screening Kirsten Jewell, BSc, BPHE (Meds 2012) Faculty Reviewer: Dr. Murad Husein, Department of Otolaryngology, UWO

bstructive sleep ap nea syndrome (OSAS) is part of the spectrum of sleep disordered breathing (S OB) and is estimated to occur in about 2% of the pediatric population , 1 whereas 2-5% of adults are affected 2 The peak incidence of OSAS is in pre-schoo lers, when ton illar hypertrophy i most common .3 Like adu lt OSAS, pediatric OSAS is caused by periods of complete or partial upper airway collap e during leep, disrupting nonnal sleep patterns and resu lting in intennittent hypoxia durin g apne ic and hypopneic episodes. It i believed that OSAS res ults from a combination of anatomic abnormalities resulting in decreased space and increased pressure in the upper airway, and neuromuscular or funct ional abnorma lities that cause decreased muscle tone wh il e sleeping and lead to periodic a irway co ll apse.3•4

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There is an increas ing awarene s about th e preva lence a nd consequences of OSAS in the adult popul ation among primary care physic ian s, a ll ow ing for improved screeni ng, diagnosis and treatment. 5 However, the recognition of thi s disorder in the ped iatric population is much more diffi cult, and current screening among primary care ph ysicians is inadequate 6 Children with OSAS present with different symptoms, have different ri sk factors , different pathophysio logy, and require different manage ment strategies than in adults.4 •5.7

CLINICAL IMPORTANCE OSAS in chi ldren has been shown to contribute significantl y to childh ood morbidity with consequences seen in multiple systems.The severity of sleep apnea has a dose-dependent re lationship with decreased left ventricular function leadin g to congestive heart failu re and cor pulmonale. 1 Plasma C-reactive protein level , a marker of inflammation with an important ro le in atherogenesis, have a lso been shown to be elevated in children with SDB,8 and fasting in ulin levels a lso seem to correlate with the disease severi ty, independent of BMJ.9 Failure to thrive and a low weight index have been noted in children with OSAS , possibly du e to changes in hormonal release during apneic episodes. 1o

It is known that OSAS in adu lts resu lts m daytime hypersornnolence and psychological seque lae such as di sturbed

concentrat ion and memory,2 however in ch ildren the deficits in neuropsychologica l and behavioural functioning caused by untreated OSAS can severely affect deve lopment, interfere with learning, and cause symptoms that may be diagnosed as attention-deficit hyperacti vity disorder (ADHD). In one well- known tudy, it was found that 33 % of chi ldren with ADHD exhibited symptoms of SOB w hile only about I 0% of children without AD HD in the study ex hibited such symptoms, with the auth ors postulat ing a causa l relati onship . 11 This hypothe is has been strengthened by the finding that symptoms of inattention and hyperactivity predictably improve after surgica l treatment for OSAS . 12

DI AGNOSIS RJ SK FACTORS Obesity is a common ri sk factor in both adu lts and chil dren, as increased fatty tissue in th e neck resu lts in increased upper airway resi tance. 13 However in childrenOSAS is sti ll most common ly related to ade notonsillar hypertroph y.3.7 Obstructive leep apnea is also assoc iated with oth er medi ca l disorders such as Down syndrome, anatomic crani ofac ial abnorn1a li ties such as micrognathi a, neuromuscular disease including cerebral palsy, and conditi ons such as sickle cell disease and laryngo malac ia. 1 Children with any of th ese conditi ons should be seen as high-ri sk and carefu ll y screened .

HISTORY A thorough sleep hi story should be taken from the parents, aski ng spec ifica ll y about I) snoring, 2) apneic episodes,3) laboured mouth breathing, and 4) restles ness.3 Habitual (ni ghtl y) snoring is the most sen iti ve indicator, as OSAS is rarely seen in its absence. I However, snorin g occurs in up to 12% of chi ldren and therefore ha poor spec ificity. I Differentiati ng between primary noring and OSAS can be difficult based on hi story alone. Note that th e loudness of snorin g does not necessaril y corre late to the degree of obstru ction !1 Dayt ime symptoms may include excessive daytime sleepi ness, or more commonl y, hyperactivity with attention and concentrat ion prob lem , possibly resulting in behavioura l difficulties and learning prob lems. The Canadian Paedi atric Society and Coll ege of Fami ly

Table 1. Differences in th e C linical Presentation ofOSAS between Children and Adults Most Common Ri sk Factor Daytime Symptoms Epidem io logical Di stribution Polysomn ograph Findings Most Common Treatment

C hildren rronsillar hypertrophy Obesity is secondary) Hyperacti vity!Jnattention 1:1 Males to Females !Awakening durin g REM sleep Fewer arousa ls Surgery (adenotonsi lectomy)

UWOMJ I 80 :21 Fall2011

Adults Obe ity !Daytime sleepiness ~ : 1 Ma les to Females !Awakenin g during slow-wave sleep More arousals CPAP

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Phys icians of Ca nada endorse the Greig H ealth Record which recommends ask ing about s leep habits, daytime somno lence as well as co ncentration and irritabili ty at a ll periodic hea lth visi ts for children ages 6-17. 14 The ' BEA RS' scree nin g qu esti o ns, a use r-fri endl y too l th at encourages obta ining sleep informati on fro m pediatric patie nts, has been shown to increase the like lihood of identifying s leep problems in a primary ca re setting, 15 a lthough it has not been va lidated to spec ifi call y identi fy OSAS.

PHYSICAL EXAM Adenotonsillar hypertrophy may be u pected o n phy ica l exam by the observation of mouth breathing, hyponasa l speech, or direct vis ualizati on on exa minati on of the o ropharyngea l cav ity, I a lthough vis ual inspecti on may give a fa lse impress ion of to nsill ar s ize and is therefore not a re liable method of diagnosis. 1 Refe rra l to an otolaryngologist wi ll a ll ow c loser visua lization of the tonsil s, adenoi ds, tongue base, and soft palate through fl exible laryngoscopy, and may detect subtl e structural abnorm a lities in the a irway. Recognition of risk fa ctors for OSAS such as cra ni ofacia l abnormalitieso r obesity on physical exam may also increase the c linician's suspicion of the diagnosis.

FURTHER TESTING Audi otapes or videotapes taken by the parent of th e sleep ing child may sometime be used by healthcare tea m to li ten and watch for observable apneic episodes. tudies exa minin g the reliability of this method of testing have found mixed results w ith genera ll y poo r predi cti ve va lues 3 While this is a non-invas ive and ava ilable means of creening and may be of orne use to c lini c ians, if the results are negative and you are still suspi c ious of OSAS in a pati ent, they sho uld be referred for a sleep tudy. The go ld standard for di agnos is of OSAS is a sleep stud y, or polysomn ograph y. It will re liabl y differentiate betwee n primary snoring and 0 AS, a nd ca n dete rmin e the seve rity of th e syndrome. Results mu t be interpreted based on age-adjusted criteri a, as OSAS affects sleep pattern s in children di ffe rentl y th an in adults. 1 C hildren wi th OSAS ex peri ence grea ter obstru cti on during REM sleep, 16and have fewer aro usals associated with apneic epi sodes. 7 C hildren also ex peri ence greate r desaturati o n durin g apne ic epi odes. 3 Theduration of obstructi on req uired for a definition of apneaand the thresho ld number of apne ic episode for a diag no i of a di order must be adjusted due to th e increased respiratory rate see n at base line in children, and it is common to see hypoxia due to prolonged parti al obstruction rather than the cyc lical complete obstruction see n in adults. I Thi s is known as obstructive hypoventil atio n. World w ide, the demand fo r po lyso mnograph y i hi gh but provi sion is limited and is costl y. The refo re it is often diffi cult to obtain thi s test in a tim e ly fashion 3 In th e absence of a n eas il y accessible s leep lab, ni ght oximetry testing may be co n ide red, meas uring epi sodes of desaturati o n througho ut the ni g ht with an 0 2 saturation probe on the c hild 's finger. Thi s te t ge nera ll y ha a good pos iti ve predicti ve va lue, but if it is negati ve th e pati e nt should sti ll undergo poly omnography to rul e out OSAS. 17

MANAGEMENT Adenotonsillecto my is usuall y the most appropriate the rapy fo r children with OSAS. In children with documented adenotonsillar hypertrophy, 75 to I 00% wi ll have symptom resoluti on as we ll as normal po lyso mnograph res ults afte r surgery. 1 Patients with obes ity or unco rrected crani ofacia l abnormalities may see poorer results on post-o perati ve po lysomn ograph y. 1

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"BEARS" Screening Questions: B=Bedtime Issues E=Excessive Daytime Sleepiness A= Night Awakenings R=Regularity and Duration of Sleep S=Snoring Studies have repeatedl y shown dramatic improvements in quality of life sco res, behavioura l symptom s, depression , hyperacti vity and somatizati o n for c hildren with OSAS after adentons ill ectomy. 18 Interesting ly, c hildren w ith milder form s of sleep di so rdered breathing also show imilar improvements after the surgery. As with a ll therapies, the ri sk of the procedure must be considered. The mo t serious ri sks of ade noto nsillectomy include respiratory complicati ons, and it is thought th at patie nts with more evere OSAS o n polysomnography pre-op a re more likely to ex peri ence respiratory com promi se post-op. 12路 18-20 Therefore these patient hou ld be ho pitalized overnight and mo nito red carefull y post-operatively. For patients with incomp lete resolution of symptoms after surgery, or for those patients w ho are not surg ical candidates, continuou posi tive airway pressure (C PAP) therapy has been shown to be effecti ve. 1 However, it i often not to lerated in the yo un ger population and must be frequent ly adju ted to fit the growing child, resultin g in poor compliance. lt is also importa nt to assess for and treat behav ioural sleep di stu rbance in children diagnosed wi th OSAS, e pecially those that continue to have daytime symptoms. Behavioural sleep di sturbances including bedtime resi tance, problematic leep a ociation , a nd prolo nged nocturn a l awakeni ngs, have a hi gh co-morbidity with OSAS in children, and inde pende ntl y put th e c hild at an increased risk for neurocogniti ve and behavioural issues. 21 Therefore it is important to implement behavioural interventions w hile concurrently in vest igating and treati ng for OSA

SUMMARY Primary ca re phy icians have an impo rtant rol e to play in the identificat ion and di agnosis of OSAS in c hildre n. However sleep di sorder are underdi agnosed in primary care practices, primarily beca use ph ys icians do not ask pa re nts about the symptoms of di so rde red lee p. In genera l, it i difficu lt to accurately diagnose OSAS on hi story and physica l examin ation alone. Howeve r, primary ca re ph y icia ns s hould be perfo rmin g reg ular creening for symptoms of OSAS as recomme nded by Ame rican Acade my of Pedi atri cs. norin g is the most sens itive indicator. If clinical suspic ion is hi gh based on risk factors and/or hi story and phy ical exa minati on, th e chi ld ho uld be referred to an otolaryngo log ist or direct! ~ to po lyso mnography for furth e r testing. Complex patient , mcludmg mfants and those with co ngenital abnormalities, should be refened to an otolaryngologi t. It is important to ide ntify and treat pediatn c O~AS early in order to prevent serious morbidity, including neurobehav10ural seque lae such as symptoms of inattentiveness and hyperactivity.

REFERENCES I. American Academy of P~di atri cs. C lini ca l practi ce guide line: diagnosis and manage ment of childhood obstructive sleep apnea syndrome. Ped iatrics. 2002; I 09(4):704-12. 2. Chung A, Jairam S, _Hussa in MRG , hapiro M. How, what, and why of sleep apnea. Perspectives for pnmary care phys ic ian . an Fam Phys ician. 2002 ;48 : I 073-80.

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3. Balbani AP , Weber AT, Montovani JC. Update in ob tructive lee p apnea syndrome in children . Rev Bra Otorrinolaringol. 2005 ;71 ( I ):74-80. 4. Powell , Kubba H, O ' Brien C, Trem len M. Paediatric obstructi ve sleep apnoea. Clinical Otolaryngo logy. 20 I 0;35(5):4 18-23. 5. Erl er T, Paditz E. Ob tructi ve sleep apnea syndrome in children: a slateof-th e-art review. Treat Respir Med . 2004;3(2): I07-22 . 6. Meltzer LJ , John on C, Crosette J, Ramos M, Mindel! JA . Prevalence of diagnosed sleep di sorders in pediatric primary care practi ce . Pediatri cs. 20 I0; 125(6):e 1410-8. 7. Choi JH , Kim EJ. Choi J, et al. Obstructive leep apnea syndrome: a child is not ju t a mall adult. Ann Otol Rhinol Laryngol. 20 I0; 11 9( I0):656-6 1. 8. 8. Tauman R, lvanenko A, O' Brien LM , Gozal D. Plasma -reacti ve protein levels among children with Jeep-disordered breathing. Pedi atrics. 2004 ; 113(6):e564-9. 9. 9. Eva RC de Ia, Baur LA, Donaghue K , Waters KA . Metabolic correlates with obstructi ve sleep apnea in obese subjects. J Pedi atr. 2002 ; 140(6):654-9. I0. I 0. Nie minen P, Lopponen T, Tolonen U, et al. Growth and biochemical markers of growth in chi ldren with snori ng and obstructi ve sleep apnea. Pedi at ri cs. 2002 ; I 09( 4):e55. II. II . Chervi n RD , Dillon JE, Bassetti C, Ga noczy DA, Pituch KJ . Symptoms of sleep disorders, inattenti on, and hyperactivity in child ren. Sleep. 1997;20( 12): 11 85-92. 12. 12. Mitchell RB , Kelly J. Behavioral change in children with mild sleepdisordered breathing or obstructive sleep apnea after adenoton illectomy. Laryngo cope. 2007 ; 117(9): 1685-8. 13. 13. Verhu lst SL, Van Gaal L, De Backer W, Desager K. The prevalence, anatomical correlate and treatment of sleep-di ordered breathing in obese children and adole cents. Sleep Med Rev. 2008; 12(5):339-46. 14. 14. Greig A, Constantin E, Cars ley S, Cummings C. Preventi ve health care visits for children and adolescents aged six to 17 yea rs: The Greig Health Record- Executi ve Summ ary. Paed iatr Child Hea lth . 20 I 0; 15(3): 157-62. 15. 15. Owens JA , Dalze ll V. Use of the " BEARS" sleep screening tool in a pediatri c residents' continuity clinic: a pilot study. Sleep Med. 2005;6( I): 63-9. 16. 16. Muzumdar H, Aren R. Diagnostic issues in pediatric obstructi ve sleep apnea. Proc Am Thorac Soc. 2008;5(2):263-73 . 17. 17. Wong T. Polysonmnography in Chi ldren : 2006 Update. HK J Paediatr (New Seri es). 2007; 12( I ):42-46. 18. 18. Ye J. Outcome of Adenotonsillectomy for Obstructive Sleep Apnea Syndrome in Chi ldren. Ann Otol Rhino I Laryngol. 20 I 0;(8):506-5 13. 19. 19. Mitchell RB , Kelly J. Quality of li fe after adenotonsillectomy for SDB in children. Otolaryngol Head Neck Surg. 2005 ; 133(4):569-72 . 20. 20. Tran K.D, Nguyen CD, Weedon J, Goldstein NA . Child behavior and quality of life in pediatri c obstructive sleep apnea. Arch Otolaryngol Head Neck Surg. 2005; 131 ( I ):52-7. 2 1. 2 1. Ye J, Liu H, Zhang G, et al. Postoperati ve respiratory compli cati on of adenotonsillectomy for obstructive sleep apnea syndrome in older children : preva lence, ri sk factors, and impact on clinical outcome. J Otolaryngol Head Neck Surg. 2009;38( I ):49-58 . 22. 22. Byars K, Apiwattanasawee P, Leejakpai A, Tangchityongsiva S, Simakajomboom N. Behav ioral sleep di sturbances in children clinica ll y referred for evaluati on of obstructi ve sleep apnea. Sleep Med. 20 II ; 12(2): 163-9.

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An interdisciplinary approach to voice disorders Emma Farley (Meds 2013), Ashley Kim (Meds 2013) Faculty Reviewer : Dr. K. Fung

he larynx serves th e du al purpose of airway protection and phonati on. It is covered by the epig lottis during swallowing, and i patent during re pirat ion and phonati on, during w hi ch a ir passes past the modified sides of the larynx, the voca l fold s or cords. The upper border of the conus e lasti cus is thi ckened , which forms the true voca l fold s. Histolog ically, the outermost layer of the voca l fold is campo ed of tratified squamou epithe lium . Deep to this li es the lamina propri a, a fl exible fibrou s layer contai ning e lastin, collagen, an d fibroblasts. The la mina propria is divided into three c linicall y impo rtant layers - superficial , intermediate and deep, which become gradually mo re stiff a th e co ll agen to e lastin rati o increases. Deep to this membranous cove r lies the body of the thyroaryten o id muscle.

T

Phonation requires the prese nce of not on ly the vibratory voca l fold s, but other upper airway structures - the pharynx, ora l and nasal cavities - for resonance and articu lation . Phonation is produced during the g lotti s cycle. The fir st step is the accum ul ation of air press ure beneath the approximated voca l fo lds. At a particular press ure, call ed th e phonati o n threshold pre sure, th e voca l fold s begin to part in a wave- li ke fashion from inferior to superior. The voca l fold s are s imultaneo us ly moved laterally by the a ir column , and quickly return to the midline du e to the ir intrinsic e lasti c properties. Thi cycle repeats approximate ly I 00 tim es per seco nd in men and 220 times/second in women 1. The a mplitude, frequency, wave morpho logy and periodicity (vo lume, pitch and voca l quality, respecti ve ly) are va ri ed by c hanges in a ir press ure and/or ti ss ue quality. Amp litude is increased or decreased by providing a greater or lesser ex haled force , paired with an in crease or dec rease in tens ion of voca l fo lds (affected princ ipa ll y by the th yroa ry tenoid mu c le) . Pitc h is increased by co ntractio n of the cricoth yro id musc le, whi c h lengthe ns and thin the voca l fold , an d dec rea ed by co ntract ion f th e thyroaryte no id muscle, whi ch sho rten th e fold a nd increases th e ir mass . Di so rde rs o f and di sruption s to th e voca l fold s may have d evas tat in g co nsequ e nce in eve ryd ay co mmuni ca ti o n, a nd es peciall y for th ose who re ly o n thei r vo ices profe s io na ll y. T hi arti c le wi ll address so me of th e most common voca l di sorders of profess iona l s in ge rs, th e ir ca use, ide nti fi ca tion , mana ge ment, prevention , and th e ro le of a multidi sc iplinary tea m in mainta ining voca l hea lth . VOCAL HYGIENE AN D T H ERAPY First- li ne trea tm e nt for many orga ni c voca l diso rders, such as nodu les, po lyps and cysts is voca l therapy. Vocal th erapy serves to impro ve voca li za ti on techn iqu e , a nd to minimi ze harmful beha v iours, whil e max imi z ing hea lthful o ne . Ho lmberg et al. used voice the ra py in the treatment o f voca l fo ld nod ul es, and showed perceptual improvement in voca l qua li ty, a nd reduction in nodul e

24

size2 The ir protocol for vocal therapy co ns ists of 5 d ifferent approaches to voca l health, and it was concluded that the therapy as a who le is required to significantly improve voca l qua li ty 2 . The first is voca l hyg iene, whi ch enta ils patient ed ucation on normal phonation, types of abu ive behav iours (vo ice overuse) and a busive substances (smoke and caffeine), and etiology and conseq uence of voca l nodul es. The second i re piration - a focu s on reducing the effort of speech breathin g and exercises to tra in the proper management of air suppl y. Third are direct faci litation mea ures which aim to reduce loudness, coup led wit h "yawn-sigh" exercises, w hi ch rel axes voca l muscul atu re and so ft en voca l onset. The fourth is relaxation techniques and stress management. Last, the patients were instructed to carry ove r all of th e above tec hniques to real ituations 2 . One rando mi zed control trial demonstrated the efficacy of voca l th erapy in pati ents who acquired voca l impairment after treatment (either laser o r radi o thera py) for early g lo ttic cancer. Significant impro eme nt were no ted bo th subj ective ly by patie nt questionnaire and thro ug h objective vo ice parameters3 . A econd e lement in voca l technique is the voca l warm-up. Wa rm-up exe rc ises inc lude !retc hes of the fa ce and torso, deep breathing tri gge r , sustaini ng vowe l o n various pitches wi th varyi ng intens ity, humming and lip-buzzing, g lide , and the production of con o nants. The a im of the wann-up is to max imi ze pho nati o n, reso nan ce and respira ti on. Elli ot e t al. , hawed that voca l warm-up red uces vi cos ity of the voca l fo lds, but that this result a lone does not uniforml y increase ea e of phona ti on (pho nati o n thre hold pres ure) amon g subjects 4 • It is in tead hypoth e ized that the voca l wa rm -up affect othe r prope rti es of the voca l fold s, uc h as amplitude , vibrati on peri odi c ity, and nervous co nt ro l of laryngea l muscles 4 .5. Bay loc k condu cted pre liminary resea rc h that studied the effect of voca l-wam1 up in four ubj ects w ith vo ice di sorders6. He reported a s ignifi ca nt improve me nt in vo ice produ ction accordi ng to acou tic mea ures and se lf- ratin g, but noted that more studi es were needed to co rroborate th ese re ults6 A rec urring prob lem in the li terature seem s to be the inte r-subject variab ili ty in voca l phys iology, and the d ifficu lty o[ findin g an adequate measure to asses the different effects of th e wa rm-up 4•5•6 . Therefore, the efficacy of wam1 up in vo ice di sorde rs is still inconclusive. A third co ns iderati on in the manageme nt of any voca l di sorde r is th e prompt treatment of secondary dysphonia . Exa mples are acid re flux , acute laryng iti s, and a ll ergic laryng itis. One of the mo t important c~ u ses th at sho uld be rul ed o ut is laryngop ha ryngea l re flu x (LPR). Un hke the sto mach the larynx does not have the intrinsic ab ility to protect from gastri c acid re lated mu co a l damage7.11 . In add1t1 o~ to the mherent u ceptibility of the la rynx to aci d dam age, ca rb~m c a ~h ydrase type 3 ( important in regul ating pH by producing a lkalme bica rbonate) IS normall y present in true voca l fo ld howeve r, dimini shed or abse nt in voca l fo ld s affected by LPR7 . The '

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symptoms of LPR include throat clearing, hoarseness, excessive mucus, cough, globus sensation as well as laryngoscopic findings which include posterior laryngeal edema, true voca l fold edema, and p eudosulcus9 •11(Figure 2). The genera l approach to the treatment of LPR is simi lar to the treatment of gastroesophagea l reflux9. Di etary modifications consi t of limi ting foods and beverages containing caffeine, alcohol and peppermint, which may weaken lower esophagea l sphincter tone 11 . The ev idence surrounding the use of PPis for the management of LPR remains somewhat inconclusive9- 11 . However, for patients with LPR who have symptoms that impact their profess ional or socia l responsibilities (like si ngers, actor , lecturers), it is recommended that treatment with PP! s be started at high do es 11 , as well a adm ini strati on of H2 blocker and antacids when reflux is anti cipated after meals9 In all cases of voice di sorders, a multidi sci plinary team co nsistin g of oto lary ngo logis ts, family physicians, speec h pathologi sts and voca l teachers are required . While speaki ng voice is sometimes unaffected by voca l fold lesions, the reduced vocal range, increased effort and impaired endurance experienced by professional singers, have far greater implications to their ca reer 12. The pos ibility of secondary causes of dysphoni a such as LPR, hi ghli ght the significance of a thorough hi story and physical , which can revea l risk factors and possible etiologies that lie outside the larynx . The role of the family physician is parti cularly important in isolating and directing appropriate treatment or referratl 4 The role of the speech language pathologist lies in the education of regul ar speech, assisti ng in phonati on, articu lation, respiration and resonance 12 Voca l teachers contribute specia lized experti se in vocal hygiene, wam1 ups and education of proper singi ng techniques, as well a profess ional guidance. Not surpri singly, it is wide ly appreciated that combined interdisciplinary treatment modalities support better outcomes for patients 12-14 . PROBLEMS FOR SINGERS: VOCAL FOLD LESIONS

Benign vocal fold le ion are common in profe sional vo ice u er . The most likely culprit of these lesions include voca l overuse, misuse (excess ive mu sc le tension) an d ab use (voice ove ru se o r whi spering) 15. During any of these acts, there is excess ive mechanical stress applied to the voca l folds. The mechanica l stres of excess ive vi brations of the voca l fold affect the voca l fold mucosa itself, rather than the underl yi ng muscu lature 16·17 , resulting in fatigue damage 18. Vocal ti sue traumatized by repeated co lli sion forces, vocal fold accelerations and decelerations, and heat di ssipation , which result in tissue brea kdown and remodelling 16·17·19 The remodelling phase induces mass lesions, including voca l fold nodules, polyps and cyst . While the histo logy and pathology of benign vocal lesions is not fully understood, some studi es try to correlate the different types in order to detem1ine the best pos ib le management 15. Vocal polyps are benign , hyperplasti c lesions of the laryngea l mucosa. They are normall y si tuated unilaterall y20 and anteri orl y on the vocal fold 21. It is hypothesized that voca l polyp are due to areas of vibration-induced hyperaemia and vasodil ation resulting in edema21 . The edema then leads to degenerati on or fibrosis21. Voca l polyps are also associated with smoking and acid reflu x22 . First-l ine treatment is generally regarded to be voca l behav ioural therapy' S, but debate remains over whether patients should primarily attempt voca l therapy measures (as in the case of voca l fold nodule ), or proceed immediately t o s ur gica l int e r ve nti o n . A we ll-d efin e d microphonosurgery ex ists, developed by Hochman and Zeitels, which preserves more of the voca l fold microstructure than typical cold instrument or laser removal22 . Stajner-Katusic et al. , in vestigated the vocal quality of fi ve males, before, one month after and six years after surgical vocal polyp removal. Their data showed significant improvement of vocal quality across several voca l measures,

including elf-estimation by the participants23 . Conversely, Cohen and Garrett showed that voca l therapy was effect ive in improving voca l quality, by reducing the size of voca l polyp (but not eliminating voca l polyps) in 50% of their participants, whil e the other half required surgery 24 The response to treatment was attributed to the polyp type. Translucent (immature, edematous) polyps, seen by videostroboscopy, were significa ntl y more likely to benefit from voca l therapy, when compared to fibrotic , hya line, or hemorrhagic (matu re) polyps 24 In add ition, incomplete glotta l closure after voca l therapy was di scussed as a potential indi cation for surgica l referral. Without glotta l closure, ai r would sti ll escape during si ngi ng and phonation , resulting in persistently inefficient vocal use, sugge ting the need for aggressive treatment 24 . ln this study, longtem1 follow-up wa not performed , and there was no accounting for differences in methodology between voca l therapists. It was concluded that although not for everyone, there is a speci fi e patient populati on that would max imall y benefit from voca l therapy alone, while others should proceed directly to surgery 24 No dul es , o r " si nger ' s nodes " occ ur bilaterally a nd symmetrica lly on the voca l fo ld and are attributed primaril y to voca l abuse or mi suse 11 ·25 (Figure 3). Vocal fold nodul es, simil arly to polyps, are benign areas of edema and fibrosis 25 . It is worth noting that the difference between nodul es and polyps is not always evident, and there is a lack of clear hi stologica l distinction 20 Vocal fold nodules present with hoa rseness and breathiness due to a fa ilure of the vocal folds to approx imate, pitch breaks and fat igabi li ty 25 . As detailed above, the fir t line treatment for voca l nodul es is behaviourall y-ba ed vocal therapy3 An interventi on review in 2009 found that there were no high quality randomized controll ed trial , which compared surgica l and non- surgica l interventions for vocal nodul es 26 The article reiterates the lack of definite hi tologic di stinction between nodules and polyps, as well as the lack of goldstandard assessment measures of voca l quality a barriers to performing adequate trials 26 Other voca l fold pathology that is important to rul e out by an otolaryngologist, include laryngeal papi llomatos is, granul omas, dysplasia and carci noma, all of which have been documented in singers as causes for voice impairment. CONCLUSIONS

Like many other occupati onal hea lth issues, dysphonia is associated with decreased quality of life, and may lead to loss of work in po pul a ti o ns whose profess io ns re ly o n vocal ab ility 27 Otolaryngo logists provide a major role in both surgical and non surgical correcti ons of nodul es that are not amenable to con ervative, behavioural or voca l therapy treatments. Surgery was once beli eved to be profess ional sui cide for singers a decade ago 13 , but thi s rapidly changing perspective reflects the advances in microsurgery that have created positive outcomes for appropriately selected patients22,24 Voice med ici ne reiterates the importance of multidisciplinary care and combined experti se that cater to the overall goals of a particular patient population . A always, health care profe sionals should be aware of these modaliti es that lie outside of tradi ti onal medi cine. REFERENCES I. Sulica L. The Voice: Anatomy, Phy iology and Clinical Evaluati on. Bailey B, John on J, eds., Otolaryngology - Head & Neck urgery, 4th ed. Philade lphia, PA: Lippincott Williams & Wilkins 2006 :817-827 2. Holmberg EB, Hillman RE, Hammarberg B, Sodersten M, ~· Efficacy of a behaviorall y ba ed voice therapy protocol for voca l nod ul es. l..Yci.ce. 200 I Sep; 15(3):395-4 12. 3. van Gogh CD, Verdonck-de Leeuw IM, Boon-Kamma BA , Rinke! RN , de Bruin MD, Langend ijk JA , Kuik DJ , Mahieu HF. The efficacy of voice therapy in patients after treatment for early glottic carcinoma. Cancer 2006 Jan I; I 06( I):95- 105 4 . .El.l.illt.N, Sundberg I, Grammin g P. What happen during vocal warm-up? l..Yci.ce. 1995 Mar;9( 1): 37-44.

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5. Milbrath RL, olamon N P. Do voca l warm-up exercises allev iate voca l fatigue? J Speech Lang Hear Res. 2003 Apr;46(2):422-36. 6. Blay lock TR. Effects of systemati zed voca l warm-up on vo ices with di order of va rious etiologies. J Voice. 1999 Mar; 13( I ):43-50. 7. Habe oglu M. Habesoglu TE. Gunes P. Kini s V. Taros SZ. Eriman M. Egeli E. How does reflux affect laryngea l ti ssue quality? An ex perimental and hi stopathologic animal study. Otolaryngo logy - Head and Neck Surgery 20 I 0. 143(6):760-764 8. Johnston N, Bulmer D, Gill GA, Paneni M, Ross PE, Pear on JP, Pignatelli M, Axford SE, Dettmar PW, Kaufman JA. Cell biology of laryngea l epithelial defenses in health and di sease: further studi es. Ann Otol Rhino! Laryngo l. 2003 ; 11 2(6):48 1. 9. Franco, RA . Laryngopharyngea l reflu x. Uptodate [onlin e) Retri eved 30 June 20 11 from www uptodate com 10. Kaufman JA, Aviv JE, Casiano RR, haw GY. Laryngopharyngea l reflu x: posi ti on sta tement of th e committee on peech, voice, and swall owi ng di orders of th e American Academy of Otolaryngology - Head and Neck urgery. Otolaryngol Head Neck urg 2002 ; 127.32 . II . Detecting the other reflu x di sease. Madani A, Wong E, Sowerby L, Fung K, Gregor JC. J Fam Pract. 20 10 Feb;59(2) : 102-7. 12. Behl au M, Oliveira G. Vocal hygiene for the vo ice profess ional. Current Opinion in Otolaryngology & Head and Neck urgery 2009, 17: 149- 154. 13. Sataloff RT. Arts medicine: an interdisciplinary paradi gm. Ear, Nose, & Throat Journal. 84(8):462-3, 2005 Aug. 14. Rosen CA , Anderson D, Murry T. Eva luating hoar eness : keeping yo ur patient 's voice healthy. Am Fam Phys ician 1998; 57:2775 . 15. Johns MM . Update on th e etiology, diagnosis, and treatment of voca l fold nodules, polyps, and cysts. Curr Opin Otolaryngol Head eck Surg. 2003 Dec; II (6):456-6 1. 16. Haji T, Mori K, Omori K, lsshi ki . Ex perimental studi es on th e viscoelasti city of the voca l fold. Acta Otolaryngol. 1992; 11 2( I ) : 15 1-9. 17. Haji T, Mori K, Omori K, lsshiki N. Mechani cal properties of the voca l fold. Stress-strain studi es. Acta Otolaryngol. 1992; 112(3):559-65. 18. Tao C, Ji ang JJ . Mechanical stress during phonation in a self-osci ll atin g finite-element vocal fold model. J Biomech. 2007;40( I 0):219 1-8. Epub 2006 Dec 2 1. 19. Ti tze IR, Svec JG, Popolo PS. Vocal dose measures: quantifying accumul ated vibrati on ex posure in voca l fold ti ssues. J Speech Lang Hear Res. 2003 Aug;46(4):9 19-32 . 20. Ci priani NA, Martin DE, Corey JP, Portuga l L, Caballero N, Lester R, Anthony B, Taxy JB. The Clinicopathologic Spectrum of Beni gn Mass Lesions of the Vocal Fold due to Vocal Abuse. tnt J Surg Pathol. 20 II Jun 16. 2 1. Kambic V, Radsel Z, Za rgi M, Acko M. Vocal cord polyps: incidence, hi stology and pathogenesis. J Laryngol Otol. 198 1 Jun ;95(6):609- 18. 22. Hochman II , Zeitels SM . Phonom icrosurgical management of vocal fold polyps: the subepithelia l mi croflap resecti on technique. J Voice. 2000 Mar;14( 1): 112-8 . 23. Stajner-Katusic S, Horga D, Zrin ski KV. A longitudinal study of voice before and after phonos urgery for removal of a polyp. Clin Lingui t Phon. 2008 Oct-Nov;22( I0-11 ):857-63 . 24. Cohen SM, Garrett CG . Utility of vo ice therapy in the management of voca l fold polyps and cysts. Otolaryngol Head Neck Surg. 2007 May; 136(5):742-6. 25 . Lancer JM , Syder D, Jones AS, Le Boutilli er A. Vocal cord nodul es: a review. Clin Otolaryngo l Allied Sci. 1988 Feb; 13( I):43-5 1. 26. Pedersen M, McG lashan J. Cochran e Database Syst Rev. Surgical versus non-surgical intervention s for voca l co rd nodu les. 200 I ;(2):CDOO 1934. 27. Ruotsalainen JH, Sell man J, Lehto L, et al. Interventi ons for preventing voice di so rders in adults. Coc hran e Database Syst Rev 2007; 17:CD0063 72.

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Transoral Robotic Surgery (TORS) Jason Xu {Meds 2013), Michal Brichacek (Meds 2013) Faculty Reviewer : Dr. Kevin Fung, Dr. Anthony Nichols

inimall y invas ive surgery has revo lutioni zed surgica l practice in the past two decades and is quickl y becoming the tandard of care aero s multiple di sciplines. In head and neck surgery, organ-preservation protoco ls and transora l lase r microsurgery have laid the fo undation fo r the recent development of transoral robotic surgery (TORS), which uses the da Vinci surg ica l robot to orally approach the throat rather than traditi onal cerv ica l incisions into closed neck spaces. ! The technique was developed at the Uni ver ity of Pennsylva nia, initiall y by demonstrating wide access to the laryngopharynx using mouth gag retractor and perfo m1 ing procedures on a canine mode l. lin 2006, they descri bed its appl ication in human patients fo r resection of oropharyngea l squamous ce ll carcinoma (OPSCC).3The FDA approved the use of TO RS in December of 2009 for resecti on of selected head and neck tumours.2

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The primary adva ntages of roboti c surgery in c lude the minimi zati on of surgica l trauma, superior visuali zati on, improved precision, and the abili ty to recreate an open surgica l experi ence .6 Additional adva ntages include better safety and morbidi ty outcomes for the patient, which are di scussed be low.Conver ely, there are certain di sadva ntages ofTO RS such as a confined operati ve fi e ld and fin ancial limitations such as the high initi al cost of the roboti c system (over a milli on dollars) and the high cost o f instruments (about one thousand doll ars per ca e) .l However, in centers where a robotic console a lready ex ists for genera l or uro logic surgery, adding head and neck cases wi ll augment value of the machine and increase prod ucti vity. I

In Decem ber of 20 I 0, Dr. Kevin Fung and Dr. Anthony N ichols from the Department of Oto laryngo logy - Head and Neck Surgery at the University of Western Ontario (UWO) perfo rmed the first TORS procedure in Canada: a TO RS upraglottic laryngectomy(Figure I ). Other options fo r the pati e nt we re e ith ero pen suprag lotti c laryngectomy with bilate ra l nec k d issecti o ns o r full course radiotherapy for 7 weeks (70 Gy) . With TORS , the patient was able to avoid temporary trac heotomy and nasogastric tube (NG) fee ding, and with negative margi ns and nodes the patient compl etely avoidedpostoperati ve radiotherapy as we ii.Thi case hi ghli ghts some of the advantages of TORS fo r the treatment of head and neck cancer, which wi ll be discussed fu rther below a long with detail s of the procedure and future directions.

SURGICAL PROCEDURE The Da Vi nci surgical platfo rm consists of a conso le, a surg ical cart, and a manipul ator unit. The TORS procedure in vo lves the transoral inserti on of two wri sted instruments anns and a central 3D endoscope.4 The console offers the surgeo n a three-dimensional magnifi ed view and allows control of the twoendowristed roboti c anns, whi ch he lps to enhance manual dexterity.5 The system a ll ows for the surgeo n's hand movements to be motion-sca led and thereby eliminates physiological hand tremor. 6 The first clinica l use of the Da Vinci robot fo r head and neck surgery involved the remova l of a benign oropharyngeal lesion and a thyroidectomy. 7,&Applications have expanded to procedures such as parathyroidectomy and skull ba ed surgery.9, I OHowever, the main application of TORS is in the treatment of ma lignancies caused by squamous cell carcinoma (SCC) which can invo lve the oral cav ity, oropharynx, hypopharynx , and larynx .6Such cases include TORS tonsillectomy, TORS tongue base resection, and TORS supraglotti c laryngectomy.

Figure l. Dr. Anthony N ichols (left) and Dr. Kevin Fung (right) fro m the Department of Otolaryngo logy - Head and Neck Surgery at the Uni ve rsity of Western Ontario,standing next to the control console of the Da Vinc i surgica l robot.

OUTCOMES Due to its relati ve in fa ncy, there are currentl y no contro ll ed studies comparing TORS procedures to their open surgical counterpart or primary chemoradiation for the treatment of oropharyn gea l cancer. However, di ffe rent case series of pati ents who underwent resection of oropharyngeal squamous cell cancer (OPSCC) by TORS show pro mi sing re ults and highlight several advantages . SAFETY No major complicati ons and acute seque lae of TORS have been re po rted . Min o r co mpli ca ti o ns in c lude tran so ra l blee din g, exace rb a ti o n of s lee p apn ea fro m posto pe ra ti ve we llin g , development of moderate tri smus, and temporary hypem asa lity of voice. lin genera l, patients who undergo TORS have lower estimated

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blood loss (<200 mL) when compared to open surgery, and none ha ve required blood transfusions. ! TORS patients a lso have a shorter ho pita! length of stay, as most are di scharged six days after OP CC re sec tion .3 ,4ln co ntr as t , patient after ope n s upr ag lottic laryngecto my wou ld typically stay I 0-14 day in ho pita! postoperatively.

ONCOLOGICAL OP CC re ection with negati ve margins in a ll patients was reported by different ca e series ranging fro m 12 to 45 patients.4, II , 14- 16 For example, in the case se ri es from the Mayo c linic, a ll 45 patients with ei ther ba e of tongue or tonsillar fo a tumors had negative margi ns after TORS resection, and 12 were able to avoid adjuva nt radi ation . II A recent publication from the Univer ity of Pennsylvania reports that, out of 50 cases, 2 patients developed distant metasta es and one patient developed both loca l and di stant recurrence of di ease following TORS resection of OPS (mean follow-up : 2 yea rs). 19More long-term onco logical outcomes are unava ilable at thi s time.

FUNCTIONAL Pre erving airway and swa llowing fun cti o n is a n important determinant of quality of life followin g oropharyngeal surgery, and large ly depends on whether the patient receive po !-operati ve radiation or chemotherapy. To date, none of the four patient trea ted with TORS at UWO have required adju va nt radiation therapy a th ey al l had negati ve margin and nodes po t-surgery (negative nodes weredetermined by patholog ical stag ing of a taged nec k di section two weeks post-TORS). In the event that patients do have positi ve node , th e adj uvant rad iation do age needed (60Gy) will be smaller than primary radiation treatment (70-72Gy), minimizing s ide effects. At other centers, reported rates of temporary tracheotomy in patients who undergo TOR range from 3% to 31 %, with an average time to decannulation of even days.4, II , 15The use of Gtube for enteral feeding shows greater va riance due to surgeon and center preference. In a case se ri es of 45 patients at the Mayo clini c, Gtubes were used in 48% of patients, with a mea n durat ion of 12.5 day .4 In another case erie of 18 patients at the Mount S inai choo l of Medicine, no feedingtubes we re used and patients were fed a pureed di et one day after urgery. I4These data suggest an advantage over primary chemoradiat ion , w he re 17-30% pati e nts a re gastrostomy-tube dependent after one year due to dysphagia 18, and open surgery, where all patients are typ ica ll y kept on NG tube for several weeks due to a pi ration ri k.

FUTURE DIRECTION With th e increasing popularity of ro boti c surgery, training guid e line and opportunities mu t be developed fo r curre nt practitioner lookin g for ce rtifi cation . Similarly, a more re idency programs acquire robot access, standardization of res ide ncy and fe ll ow hip curri culum w ill a lso be important. Currently, a ll Head and Neck Surgery fellows graduating from the Un ive r ity of Penn ylvania are trained in TOR . I The university also run s a TORS tra ining program for surgeo n from arou nd the world . As surgeons become more comfortab le with TORS , new and innovati ve procedures are being deve loped as well. One exa mpl e is transax i ll ary thyroidectomy, w here the th yroid g land i removed without ha ving to c rea te an unaesthetic cervica l sca r. The procedure was deve loped in Korea and has been pe rformed in over 300 patients a of2009.17

from case series uggest possible benefit of TORS over primary chemoradiation at preservation of wallowing function after resection of o roph aryngea l tumours. This offersa very ad_vantageous quality of life consideration, especiall y for the increasmg mctdence ofOPSC~m you ng HPV-posi ti ve pati ents. l9 However, long-ter_m o ncolog tcal outco mes of oropharyngeal cancer afterTORS resection are not yet ava ilab le, and further tudies a re warranted .

REFERENCES 1. Weinstein GS, O ' Ma lletJr BW, De ai SC, Quon H. Tran soral robotic urge ry: does th e e nd s justify the means? Current Opinion in Otolaryngology & Head and eck Surgery 2009; 17:126-13 1. 2. Uni versity of Pen n ylvania School of Medi cine. "F DA c lear TransOral robotic surgery." c ience Daily [updated 6 January 20 I 0; cited 15 March 20 11) . Available from : http "// www sciencedaily com / rel eases/ 20 10/01 / 100 104 114553 .htm 3. O'Malley BW Jr, Wei n tein G , nyde r W, Hoc kstein G. Transoral roboti c s urgery (TOR ) for base of to ngue neoplasms. Laryngoscope 2006; 116: 1465-1472 . 4. Moore EJ , Olsen KD, Kasperbauer JL. Transora l robotic urgery for orop haryngea l quamou ce ll carcinoma : a prospective tudy of feasibility and functional outcomes. Laryngo cope 2009; 199( I ):2 156-64. 5. Moorthy K. Munz Y, Dosis J. Hernandez J, Martin S, Bello F, et al. Dex teri ty enh ancement' ith robotic surgery. urgEndo c 2004 ; 18:790-5 . 6. Arora A, et al. , lini ca l appl ication of Telerobotic E T- Head and Neck surgery. Internati onal Journal of Surgery 20 II ; 1-8. 7. McLeod IK , Melder P . Da Vinci robot-as isted exci ion of a va llecul ar cy t: a case report . ar o e Throat J 2005; 4: 170-2. Lobe TE, Wright K, Irish M . ovel uses of surgica l robotics in head and neck su.rgery. J Laparoendo c dv urg Tech A 2005; 15(6):647-52. 9. Profante r C. Schmid T, Promm egger R. Bale R, Sauper T, Bodner J. Robot-assi ted media tin alparath yro idecto my. SurgEndosc 2004; 18(5): 6 -70. I 0. O ' Malley Jr BW, We in tein G . Robotic skull ba e surgery: preclinical inve ti gati ons to human clinical app li ca tion. A.rch Otolayngol Head eck urg 2007; 133 : 1215-9. II . I e li T, Kulbe r h B, I eli . Carroll W. Rose nthal E, con Magnuson J. Functi onal o utcome after rransora l robotic surgery for head and nec k cancer. Otolaryngo l Head eck Su rg 2009; 141 : 166-7 1. 12. Ikeda Y, Takami H. a aki Y, Takayama J, Niimi M, Ka n . omparative tudy of thyroi dectomies: e ndoscopic surgery versus conventional open surgery. SurgEndosc 2002; 16: 1741-5. 13. Bhayani MK , Ho i inger F , Lai Y. A hifting pa radig m for pati ents with head and neck cancer: tran ora l robo ti c surgery (TOR ). Onco logy (Willi sto n Park ) 20 10 Oct :24( II ): I 0 I 0- 1015. 14. Genden EM, Desai ung C K. Transoral roboti c surgery for the management of head and nec k ca ncer: a preliminary ex perience. Head eck 2009 Ma r;3 1(3):2 3-289. 15. Bo udreaux B . Rosentha l L, Magnu on J , ew man J R, Desmond RA , C lemons L, et al. Robot-assisted surgery for upper aerodi gesti e tract ncop la ms . Arc h Ot laryngo l Head eck urg 2009 Apr; 135(4):397-40 1. 16. Weinstein G . O'Malley BW,Jr, nyder W, hern1an E, Quon H. Transoral ro boti c surgery: rad ica l tonsillectomy. Arch Oto lary11go l Head eck Surg 2007 Dec; 133( 12): 1220- 1226. 17. Kang SW, Lee , Lee S H, Lee KY, Jeong JJ , Lee Y , a m KH , hang H , Chung WY, Park . Roboti c thyro id surgery u ing a gas les , tran ax ill ary approach and th e daVinci system : the operative outcomes of 338 consecutive patients. urgery. 2009; 146(6): 104 -55. 18. Nguyen . P, Moltz , Frank , e t a l. Dysphagia followin g che moradJ atJon for loca ll y advanced head and neck cancer. Ann Oncol 2004; 15:383- 388. 19. ohen MA, Weinstein G , O'Mall ey BW, Jr. , Feldman M, Quon H. Transoral robot1 c urgery and human papillomavirus tatu : Oncologic re ults. Head eck. 20 11 Apr;33(4) :573-80.

CONCLUS IONS TORS is a safe and minima ll y invasive surg ical tec hniquewith many ap plicati o ns in head and neck urgery. Benefits of TORS over tradi tional ope n surgery inc lude hand tre mor redu ction , better visuali za tion , and minimization of surgica l tra uma. Promi s ing data

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The role of FOG-PET and PET/CT in the diagnosis and staging of head and neck cancer Adrian Matthews (Meds 20 13), Jai Prashanth Jaya kar (Meds 2013) and Joshua Ro senbla t (Meds 2014) Faculty Reviewer : Dr. John Yoo, Department of Otolaryngology - Head and Neck Su rgery

n estimated 644,000 cases of head and neck ca ncer are di agnosed wo rldwide each yea r, w ith head and neck squam ous cell carcinoma (HNSCC) acco un ting fo r over 90% of these. Common presenting s ites inc lude the ora l cav ity, oropharynx, nasopharynx, hypo pharynx , and larynx. I While chronic tobacco use and alcohol consumption are well -establi shed ri sk facto rs,2 human papillomav irus (HPV) infection of the upper aerodi gestive tract has been cau a ll y li nked to tumori genesis.3 In particular, the increasing rates of oropharyngea l cancers, especiall y young non-smokers, has been directl y attributed to HPV infect ion.

A

The diagnostic workup of HNSCC typicall y incl udes history and physical examination, endoscopic-guided biopsy and highreso luti on co ntras t-enh anced co mputed to mogra ph y (CT ) o r magnetic resonance imaging (MRI). Whil e CT and MRI have traditionall y been the cornerstones of the imaging workup, 2-fluoro[ 18F] -deoxy-2-D-glucose positron emission tomography (FDG- PET) plays an increasing ro le in the diagnosis, rag ing and fo llow-up of HNSCC patients.! ,4,5

FDG-PET AND PET/CT IMAGING FOG, a glucose ana log labe ll ed with the radi onuc lide 18F, preferentiall y accumu lates in cell s that have an increased g lyco lytic rate - a characteri stic fea ture of cancer cell s.6 FDG-PET is thus a fu nctional imag ing modality that detects cellular metabol ic changes, unlike CT and MRI , which re ly on stru ctura l abnorma litie . The positrons emitted by the radi onuclide an nihilate nearby electrons and create photons that are captured by an array of detectors and reconstru cted into a 3D image. A lthough PET a lone is limited by its lack of anatomic localizati on, the advent of the hybrid PET/CT scanner has overcome thi s by fu sing PET and CT images acqu ired in a single session, permitting deta iled visualizati on of both structu ra l and fun ctional aspects of di sease. I ,4-6

STAGING OF HEAD AND NECK CANCER TNMSTAGING

PRJ MA RY T UMOUR Whil e PET and PET/CT have been shown to be at least as effecti ve as CT or MRI at detecting primary tu mours, these modalities are not used in ta ndard practice to T- tage new ly di agnosed HNSCC because their anatomic reso lution is not as hi gh as that of MRl or contrast-enhanced multi slice CT.9- I 3 An earl y tumour may have poor FOG uptake and its detection on the scan may be obscured by cross contamination of physiologic acti vity from surroun d ing ti ssues - the so-ca ll ed 'spill over effect' . l 4 CT and MRI are usefu l fo r initia l T-staging, since the ir high spat ial resolution and soft-tissue contrast can demonstrate subtle abnorm aliti es and acc urate ly de lineate tumour volume.

CARCINO MA OF UNKNOWN PRIMA RY In 2-9% of patients with new ly di agnosed HNSCC, cervica l node metastases are clinicall y ev ident at bi opsy but the primary tumour cannot be identifie d by conventi ona l workup, which includes phys ica l examination, CT, MRI and endoscopic-guided biopsy. l 5 PET/CT has proven to be sign ifi cantly more sensitive than CT (94 .0 versus 7 1.6%, respecti vely, P < 0.00 I) at detecting carcinomas of unkn own primary. l 6 Rusthoven et al. reviewed 16 studi es published between I 994 and 2003 and found that among 302 patients with a negati ve conventional workup, FOG-PET detected the primary tumour in 74 patients (24.5%). 17 In a more recent review, A llbraheem et al. performed a meta-analys is of 8 stud ies publi shed between 2000 and 2009 .5 FOG-P ET or PET/CT were ab le to detect the unkn own primary in 5 I of 180 patients wi th an otherwise inconclu ive workup . Delineation of a pri mary tumour i e sential fo r delivering targeted therapy, minimizing therapeutic morbidi ty caused by wide- fi eld irrad iation and improving prognosis. IS A recent report noted that findin gs made by FOG- PET changed therapeuti c manage ment in 25% of pati ents. l 9 In light of th is evidence, PET/CT may have an important ro le in the di agnosti c assessment of carcinoma of unkn own pri mary.5

CE RVICAL NO DE METASTASES

HNSCC is staged acco rdin g to the size and extent of the pri mary tumour (T), regional lymph node involvement (N) and the presence of distant metastases (M).4 Accurate stag ing at the time of di agnosis is the most important fa ctor for pl a nning manage ment and determining prognosis.4,7 Since the preservation or restoration of fu nction is a top pri ori ty in the management of patients with HNSCC, fu ncti on-sparing strategies such as minimall y invasive surgery or (chemo)radi otherapy are often considered as fi rst- line treatments .& Thorough clinica l assess ment, including imaging, is vita l to optima l staging of HNSCC. Furthermore, re-evaluation of patients fo llow ing treatment may be especiall y challeng ing in HNSCC, due to difficul ty in obtaining pathology. The fo ll owing subsecti ons rev iew the c li nica l indications for FOG-PET and PET/CT in staging HNSCC.

Cervica l node status is the most important prognosti c factor in HN SCC.7 Cure rate declines by nearly 50% when cervical metastase are present.20 Metastatic lymph nodes are found in approxi mately half of patients at the time of di agnos is.2 1 PET/CT has been shown to have better sensiti vity and specificity for patho logic cerv ica l nodes than MRI and CT, like ly because the latter rely on nodal size and contrast-enhancement criteri a w hich are not specific and can miss metastase in norm all y sized nodes .22 ,23 Neverth eless, CT is generall y used for loca l staging of clinicall y mani fes t cerv ica l nodes at initial di agnosis, due to its c linical ava ilability and accurate T-stag ing of the primary tumour.

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CLINICALLY NEGATIVE (NO) NECKS

l f clinica l examinati on fa ils to identi fy metastati c cervica l lymph nodes in pati ents with primary HNSCC , these pati ents are sa id to have a clinica ll y negati ve (NO) neck. Since th e probability that th ese pati ents actuall y have a pathologica l neck vari es between I 0-45%, electi ve neck di ssection is recommended in cases whe re the ri sk of occult cervical mets is greater th an 20% .4 While PET/CT is th e most acc urate imaging modality for detecting occult metastases, the role o f PET/CT in the asse sment of NO necks is still controversial. ? Microscopic di sease or nodal metastases located adj ace nt to th e primary tum our may evade radiographic detection and contribute to fa lse-negati ves. Two studi es reported sensitivity and specifi city ranging from 67-79% and 82-95%, respecti ve ly, leadin g the auth ors to conclude that PET/CT is not yet accurate enough to inform the need for surgical di ssecti on in cases of occult nodal disease.24,25 SECOND PRIMARY (SYNCHRONOUS) MALIGNANCY AND DISTANT METASTASES Pati ents with adva nced HNSCC are at hi gher ri sk for deve loping dista nt metastases and for prese ntin g with a second primary (synchrono us) tumour;26 the latter being defin ed a a hi sto logica ll y distinct malignancy, se parated from the primary tumo ur by at least 2cm of normal muco a.27 The cost of mi ssing distant metastases o r synchronous tumours at the time of initial di agnosis is hi gh. C urati ve therapies a re ofte n assoc ia ted w ith s ig nifi ca nt mo rbidit y, necessitati ng the careful se lecti on of patients with nonmetastati c di sease who may benefit from the treatment and not eve ntuall y succu mb to previo usly undetected di stant di sease .28 Aggressive subtypes, such as naso pharyngea l carcinoma, have a tendency to metastas ize to the lungs, li ver and bone; hence, th e conventional imaging workup fo r di stant metastases is comprised of chest radi ograph y, abdominal ultrasound, and skeletal scintigraph y (bone scan). Several reports have assessed the efficacy of P ET/CT in staging di stant metastases and sync hronous tumours and found that it is the most sensiti ve, spec ific and acc urate modali ty and may repl ace conventional tec hniques. l4,28,29 A multicentre prospecti ve study of 92 pati ents fo und th at PET/CT had a hi gher ensiti vity (63%) th an chest CT (37%), due to its ab ili ty to image the whole body with a single scan a nd detect di sta nt hypermetaboli c foc i.3 0 PET/CT can therefore be considered as th e moda lity of choice for the di agnostic workup of di stant metastases and sy nchro no us tum ours.7 RESIDUAL AND RECURRENT DISEASE The reli ance o f CT a nd MRl o n morpho logic c riteri a often makes th e detecti o n of post-treatment residual tumo ur acti vity or recurre nt disease diffi cult, since the regiona l head and neck a natom y may be di storted a fter th erapeuti c (chemo)radi oth erapy and/or urgery.4 Allbraheem et al. rev iewed th e utili ty o f PET and PET/CT for

identi fy ing disease recurrence in head and neck cancers.5 Among 7 studies published betwee n 2004 and 2009, PET or PET/CT de monstrated hi g h sensiti v ity (83 -1 00%) and relatively h1gh specificity (78-98% ) and accuracy (~1-90%~, oft~ n significantl y outperformin g CT a nd MRI. InflammatiOn and mfe~t10n are common treatment sequel ae that may increase FDG uptake_m certam . tissues; hence the addition of CT to PET is espec1ally Important m these situat{ons in o rder to distingui sh trul y patholog ic areas from postirradi ated ti ss ue. l2 ,22 The anatomica l landmarks provided by CT have bee n s h ow n to d ec rease the number of equivocal hypermetabo lic foci a nd there fo re reduce the amo~ nt non-in vas ive imaging and in vasive biopsies required for d1agnos ts of recurrence. 12 LIMITATIONS

F a/se-positives In additi o n to the post-irradi ati on cha nges di scussed above, increased FDG uptake may occur in benign hyperpl astic conditions such as th yroid or pleomorph ic adenomas . Regiona l physio logic FDG uptake in lym pho id ti ssue, ali vary g la nds, strained o r excessively used skeleta l muscles a nd activated brown fa t ti ss ue may a lso confound interpretation and be e rro neously attributed to malignancy.4,6 It is recom mended that positi ve res ults be conflfllled by biopsy.6

False-negatives Since the patial resolution of FDG-PET is limited to 4-1 Omm, it ab ili ty to precisely loca li ze sma ll tumours or microscopic tissue involvement is often dimini hed in the head and neck regi on. Tumours with low meta bolic rate and poo r avidity for FDG uptake may also be diffi c ult to c haracterize on PET scans.6 SUMMARY AND RECOMMENDATIONS In 2009 , Yoo and Walker-Dilks reviewed th e data and made recommendati o ns for the use of FDG-PET in head and neck cancer. 3 1 The gu idelines, part of an initiative of the Program in EvidenceBased Care for Cancer Care Ontario, are consistent with the findings reviewed here and are summarized in Tab le I . It is worthwhi le to note that studi es examining PET and PET/CT were not distinguished in th e report; however, th e hybrid syste m clearly confers a di agnosti c adva ntage over either modali ty alone.4-7 De pite its limitations, increa ing use of PET/CT for th e diagnosis, stag ing and follow-up of HN SCC pat ients ha pro vided phys icians with a powerful tool that will continue to improve patient outcomes as the technology advances and clinica l guideline are re fin ed . REFERENCES I. Marur • Forasti ere AA . Head and Neck Cancer: Changing Epidemiology, Diagnosis, and Treatment. Mayo C lin Proc 2008 ;83(4):489-50 I.

Table 1. Recommendations for FOG-PET in head and neck cancer. Adapted from Yoo and Walke r-Dilks3 1 FOG-PET and PET/CT are recommended for :

Diagnosis/Staging

• •

M and bil ~te ra l nodal staging of adva nced HNSCC di splaying equivocal conventional imaging Identifi catiOn of unknown pnm_ary Site, m additi on to conventional imaging and diagnostic panendoscopy stagmg of nasopharyngea l carc moma witho ut ev1dence of distant di sease

Recurrence/Restaging

• 30

restaging pati ents who are being considered for majo r salvage treatment (surgery o r other)

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2. Goldenberg D, Lee J, Koch WM , et al. Habitual ri sk factor for head and neck cancer. Otolaryngol Head Neck Surg 2004; 13 1:986-93. 3. Gi llison ML, Koch WM, Capone RB , et al. Ev idence for a Causa l Association Between Human Papillomav iru and a Subset of Head and Neck Cancers. J Nat! Cancer Lnst 2000;92:709-20. 4. Gordin A, Daitzchman M, Israe l 0. Hybrid Imaging of Head and Neck Malignancies. In: Delbeke D, Israe l 0 , editors. Hybrid PET/CT and SPECT/CT Imaging. New York : Sprin ger; 20 I0. p. 137- 17 1. 5. AI- Lbraheem A, Buck A, Krause BJ , et al. Clini cal App lications of FDG PET and PET/CT in Head and Neck Ca ncer. J Oncol 2009;2009:208725. 6. Fletcher JW, Djulbegovic B, Soares HP, et al. Recommend ations on the Use of 18F-F DG PET in Oncology. J Nucl Med 2008;49:480-508. 7. de Bree R, Castelijns JA, Hoekstra OS, et al. Advances in imaging in the work-up of head and neck cancer patients. Oral Oncol 2009;45:930-35 . 8. O'Sullivan B, Shah J. New TNM Staging Criteri a for Head and Neck Tumors. Semin Surg Oncol 2003;2 1:3 0-42 . 9. Roh JL, Yeo NK, Kim JS. Utility of 2- [ 18F] flu oro-2-deoxy-d-glucose posi tron emission tomography and positron emission tomograph y/ computed tomography imaging in the preoperati ve staging of head and neck squamous cell carcinoma. Oral Oncol 2007;43(9):887-93. 10. Ng SH, Yen TC, Liao CT, et al. 18F-FDG PET and CT/M RI in oral cavity squamous cell carcinoma : a pro pective study of 124 patients with histologic correlation. J Nucl Med 2005;46(7): 1136-43. II. Gordin A, Daitzchman M, Doweck I, et al. Fluorodeoxyglucose-positron emission tomography/computed tomography imaging in patients with carcinoma of the larynx: diagnosti c accuracy and impact on clinical management. Laryngoscope 2006; 11 6(2):273-78. 12.Schoder H, Yeung HW, Gonen M, et al. Head and neck cancer: clinical usefulness and accuracy of PET/CT image fusion . Radiology 2004;23 1( I): 65-72. 13. Ha PK, Hdeib A, Goldenberg D. The role of positron emission tomography and computed tomograph y fusion in the management of early-stage and advanced-stage primary head and neck squam ous cell carcinoma. Arch Otolaryngol 2006; 132( I) 12-1 6. 14. Ng SH, Chan SC, Yen TC. Staging of untreated nasophary ngea l carcinoma with PET/CT: comparison with conventi onal imagi ng work-up. Eur J Nucl Med Mol Imagi ng 2009;36: 12-22. 15. Jereczek-Fossa BA, Jassem J, Orecchi a R. Cervica l lymph node metastases of squamous cell carci noma from an unknown primary. Cancer Treat Rev 2004;30: 153-64. 16.Roh JL, Kim JS , Lee JH , et a l. Utilit y of co mbin ed 18Ffluorodeoxyglucose-positron emiss ion tomography and co mputed tomography in pat ients with cervical metastases from unkn own primary tumors. Oral Oncol 2009;45(3):2 18-24. 17. Rusthoven KE, Koshy M, Pau lino AC. The role of fluorodeoxyglucose positron emission tomography in cervical lymph nodes metastases from unknown primary tumour. Cancer 2004; I 0 I :2642-49. 18. Schmalbach C, Miller F. Occu lt primary head and neck carcinoma. Curr Oncol Rep 2007;9(2): 139-46. 19. Johansen J, Buus S, Loft A, et al. Prospective study of 18FDG-PET in the detection and management of patient with lymph node metasta es to th e neck from an unknown primary tumor. Results fro m the DAHANCA- 13 sutdy. Head Neck 2008;30(4 ):4 7 1-78. 20. Shah J. Cervical lymph node metastases: diagnostic, therapeuti c and prognostic implications. Oncology 1990;4 :6 1-69. 21. Dammann F, Horger M, Mueller-Berg M, et al. Rationa l diagnosis of squamous cell carcinoma of the head and neck region : comparati ve evaluation of CT, MRJ, and 18FDG PET. Am J Roentgenol 2005; 184(4): 1326-31. 22. Gordin A, Golz A, Daitzchman M, et al. Fluori ne- IS flu orodeoxyglucose positron emission tomograph y/computed tomograph y imaging in pat ient with carcinoma of the nasopharynx: di agnosti c accuracy and impact on clinical management. Int J Radi at Oncol Bioi Phys 2007;68(2):370-6. 23. Quon A, Fischbei n NJ, McDouga ll IR, et al. Clinical role of 18F-FDG PET/CT in the management of squamous cell carcinoma of the head and neck and thyroid carcinoma. J Nuc l Med 2007;48 Suppl I :58S-67S. 24. Nahmias C, Ca rl son ER, Dunca n LD, et al. Pos itron emi ss ion tomograp hy/compu terized tomo g raphy ( PET/CT) sca nnin g for preoperative stagi ng of patients with oraVhead and neck cancer. J Oral Maxi llofac Surg 2007;65( 12):2524-35 . 25. Schoder H, Carl son DL, Kraus DH, et al. 18F-FDG PET/CT for detecting nodal metastases in patients with oral cancer staged NO by clinical examination and CTIMRJ. J Nucl Med 2006;47(5) :755-62.

26. Teknos TN, Rosenthal EL, Lee D, et al. Positron emi ssion tomography in the evaluati on of stage Ill and IV head and neck cancer. Head Neck 200 I ;23( 12): I 056-60. 27. Vaamonde P, Martin C, del Rio M, et al. Second primary ma lignancies in pati ents with cance r of the head and neck. Otolaryngo l Head Neck Surg 2003 ; 129( I):65-70. 28. Chua ML, Ong SC, Wee JT, et al. Com pari son of 4 modalities for di stant metastasis stagi ng in endemic nasopharyngea l ca rcinoma. Head Neck 2009;3 1(3):346-54. 29. Liu FY, Lin CY, Chang JT. 18F-FDG PET can rep lace conventional wo rkup in primary M stagi ng of nonkeratini zi ng nasopharyngeal ca rci noma. J Nucl Med 2007;48( 10):1614-9. 30. Senft A, de Bree R, Hoekstra OS, et al. Screening for di stant metastases in head and neck ca ncer pati ent by chest CT or whole body FDG-PET: a prospective multicenter tri al. Radiother Oncol 2008;87(2):22 1-9. 3 1. Yoo J, Walker-Di lks C. PET imaging in head and neck ca ncer: recommendation . Toronto (ON): Ca ncer Care Ontario (CCO); 2009 Jan 19. 43p. (Recommendation report - PET; no. 2).

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Marijuana use: sequelae and implications for health promotion Karl ine Treurnicht Naylor (Meds 2013), Daniel James (Meds 2013) and Stephanie Gottheil (Meds 2014) Faculty Reviewer : Dr. Donald Farquhar

s of 2003 , 40% of Ameri can aged 12 yea r and older had smoked marijuana at least once. 1 Approximately 30% of Canadi an yo uths from G rades 7-1 2 have tri ed cann abi s at least o nce.2 Marijuana is the most widely-used illicit substance in Canada, with l 0.6% of th e Canadi an popu lati on reporting u e in 2009 .3 Thi s is si milar to th e US annu al fi gure of9%. 4 Global reports indicate that th e ave rage age o f first marijua na use is decreas ing, even as the average delta-9-tetrahydrocannabinol (TH C) content of cannabi s is on th e rise. This may lead to an increase in both addi cti ve pote ntial and adverse effects of marijuana use.5

A

A survey of the adult US populati o n comparin g fi gures from 1992 and 2002 suggested that th e prevalence of mariju ana use remained stable over th e decade, but the prevalence o f marijuana dependence increased significantl y. T hi s increase in marijuana use disorders has occurred in th e absence o f increased frequency or quantity of marij uana use, suggestin g that the enhanced potency of TH C may have lead to the rise in rates 6 Treatment admi ssions fo r cann abi s abuse have ri sen steadil y over the past ten yea rs, including a 2-fold increase in the US and 3-fold increases in Australia and Euro pe.7 Although publi c perceptio n remains th at cann abi is "so fter" and less dangerous th an oth er illi cit substances, cann abis use is becomin g a majo r publi c hea lth concern ; some research even sugge ts it may serve as a gateway dru g to " hard er" substances.s Furthe rm ore, mul tipl e studi es have show n an inc rea ed ri sk in marij uana users of oth er long-tenn hea lth conseque nces . In thi s paper, we review c urrent research and und e rstandip g of ma riju a na's impact o n hea lth outcomes. We also prov ide an overview of at-ri sk popu lati ons for use and ab use of marij uana, summari ze mariju ana' potenti al positi ve e ffects, a nd di sc uss implicati o ns fo r hea lth pro moti o n and va ri o us levels of preventi on.

PULMONARY EFFECTS N ume rou s studi es have shown th at the combusti o n of tobacco and marijuana produces simil ar hannful compo und .s,9 T he ri sks of mariju ana may be increased by three facto rs. Mariju ana smoke has three times more ta r and 1.5 times mo re carcinogeni c substances th a n tobacco smoke. 10 Marijuana smoke is typi ca ll y inhaled mo re deeply and held in the lungs longer: the re is more time for depos itio n of parti culate matter. Furtherm o re, marijuana ciga rettes do not conta in th e same filter apparatus as conventi onal to bacco ciga rettes. On th e oth er hand, even heavy marijuana use invo lves far le s smoke inhalation th an th e equi va lent a mount o f tobacco in a pac k-a-day smoker. One analy is of 19 previo us studi es defin ed marijua na use as smokin g I 0 or more ma rijua na ciga rettes per week for 5 or more yea rs. 1 One pac k o f tobacco ciga rettes contains 20-25 ciga rettes, and th e cigarettes ge ne rall y contain more combustib le mate ri al th an their mariju ana co unterparts.

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Smo ke - wheth er fro m ma riju ana, to bacco or any other combustible is noxio us to the airways. Thi s stimulates sho rt-term bronchitic reacti ons, including coug hing, sputum producti o n and wheezing. In tum , th ese activate th e mucocili ary esca la to r, w hi c h carries parti culate matter fro m th e bronc hi c ra niall y to be ex pectorated or swall owed. O ne systemati c rev iew fo und th at inhaling marijuana smoke can ca use clini cal dyspnea and pharyng iti , as we ll as exacerbating preex istin g pulmonary illnesses suc h as asthma and cysti c fibrosis; these effects persi ted after adju ting fo r conc urre nt to bacco use. 5 Despite these apparentl y harm fu l effects, th e review fo und no a sociation between mariju ana smoke inhalati o n and effects o n FEY I (forced !second ex piratory vo lume) or FVC (fo rced vital capac ity), DLco (diffusi ng ca pac ity of the lung of carbon mo nox ide) or airway hype rreacti vity. T he auth ors ex plained these findin gs by sugge ting th at cann abinoid pro mote the T h- 2 anti-infl ammatory immune response while ni cotine suppres es it. O ne stud y noted that the use of a vapo uri ze r when consumin g marij uana was associated with dec reased respiratory sym ptom . 11 A va pourizer is a device that heats the marijua na to th e va po ri za ti on point of the cann abinoids witho ut the use of fla me, thereby o bv iat ing th e consequ ences of smoke inhalati o n. Altho ugh the re are ma ny confo und ers in these analy es, not the least of which is th e fac t that many marijua na users cut the dri ed mariju ana w ith commerciall y-ava ilable to bacco, it can be concluded that smok ing ma riju ana exacerbates pre-ex i ting res pira to ry co mpl a ints by directl y irritatin g th e res pira to ry epithe lium . However, contrary to to bacco moke, ma riju ana smoke does not seem to ca use ob tructi ve pulmo nary di seases.

LUNG CANCE R The _extant_ litera ll.~ re on mariju ana and lun g cancer presents co nfl1 ctm g mfo rm atl on. On the o ne hand, marijuana smoke contain benzopyre ne, a carcinogeni c hydrocarbon also fo und in tobacco smoke, which has bee n _implicated in mutati o ns related to lung cancer. Ex pe nmenta l tud1 es have also demonstrated THC-induced ma lig nant cell pro life rati on a nd sugges ted tha t THC inhibits antitumo ur immunity, thu s promotin g tumor growth. In contrast, othe r v1tro m ~de l s suggest that cannabinoid may actua ll y exhibit ant1 carcmogen1 c effects. 12 In a n attempt to reconc ile these di veraent streams o f tho ught, Mehra, Moore, C roth ers et al. undertook a syste mati c review to detennine the associations between marijuana mo kmg a nd lung cancer incidence, -~i sk fa cto r , or pre malignant 1 changes. The a uth or found that manJuana smokin g bas increased tar de_h ve~ ~o lungs compa red with ciga re ttes, and marijua na smoke conta ms s1mdar carc inogen as tobacco smoke, o ften in inc reased

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concentrations. Marijuana smoking was associated with the presence of more metaplastic cells, impai red alveo lar macrophage function , and increased oxidative stress w hen compared with non-smokers. Six studies included in the systematic review reported hi stopatho logic and molecular findin gs from bronchi al biopsy; in a ll studies, marijuana smo kin g was a soc ia te d with a bn o rm a l a nd /o r precancerous alterations when compared with e ither non-smoker or tobacco smokers. One study in particular reported an additi ve effect between marijuana and tobacco use. All the e findings suggest a biological plausibility for the association between marijuana use and lung carcinogenes is. However, a cohort stud y of 65,000 subj ects showed no increase in lung cancer incidence in marijuana smoker after contro lling for tobacco use. The authors suggested that there may be methodological concerns underpinning the lack of empiri ca l support fo r increased lung cancer incidence in marijuana users, including the need fo r more detailed assess ment of marijuana exposure and longer follow-up periods. They a lso cautioned that physicians should still advise their patients of the potentia l adver e health effects of marijuana use, including premali gnant lung changes . I

While methodological factor may we ll account for the lack of evidence for an association between lung cancer and marijuana use, Melamede 13 ha summarized another line of thought: although marijuana and tobacco smoke contain s imilar carc in oge n , cannabi noi ds and nicotine present with very different cellul ar effects. Firstly, although low-doses of THC may indeed promote tumour growth, the response appears to be biphas ic; a ltern ate doses of cannabinoid have been capable of destroying cancer cells (including lung, breast, prostate, skin, and g lioma) in vitro and in anima l models. Secondly, both nicotine and cannabino id receptors are linked to signaling pathways that can tum on anti-apoptosis (i.e. preventing cell death). Nicotine receptor are fo und in respiratory epithe li al cells, whi le cannabinoid receptors are not. As such, when nicoti ne receptors are stimul ated in res piratory cell s, there is an anti-apoptotic signal; the prevention of cell death under ex posure to such mutage nic conditions (i.e. smoking) is likely to amplify carci nogenic potenti al. Thirdly, while nicotine promotes neovascul arization and thus tumour growth, cannabinoids inhibits angiogenesis and results in tumour regression. Finally, the introduction of partic ulate matte r and carcinogens into the respiratory system res ults in the creation of a pro-inflammatory state. In this ci rcumstance, cannabino ids redu ce the associated free radical production by dri ving a re lative ly anti inflammatory Th2 immune cytoki ne profile. Melamede suggests that all these critica l facto rs can ex plai n the lack of association between cannabis use and lung cancer. 13 Even in light of this controversy surroundin g cannabino ids and their association with lung carci nogenesis, Guzman has go ne so far as to suggest that cannabino ids could be used to deve lop novel anticancer therapi es. 14 In additi on to evidence uggesting inhibiti on of tumour growth, marijuana may a lso be beneficial to chemotherapy patients- it has the potentia l to miti gate nausea, vom iting, and pa in while also sti mulating appeti te.

NEUROPSYC HOLOGICAL EFFECTS Aside from its respiratory and pulmonary effects, marijuana use has been associated with neuropsycho logica l consequences. C hroni c marijuana use has hi storica ll y been associated with impaired cognition, including reduced attention, memory, higher cogniti ve function (e.g. executi ve function) and psychomotor defi cits. One study showed that after 25 days of abstinence, moderate (8-35 marijuana cigarettes/week) and heavy (53 -84 marijuana cigarettes/ week) users had decreased activity in the ri ght latera l orbitofrontal cortex and the right dorsolateral prefrontal cortex, and increased activity in the left cerebellum, compared to the contro l group, during a decision-making game . 15 Another imaging stud y, using transcranial

Doppl er sonography, showed increased cerebrovascu lar resi tance in chroni c li ght to heavy users. 16 However, these studies were small , with II and 54 su bj ects, respectively. One meta-analysis of tudies tota lling 623 chron ic marijuana users fo und that a lthough these indi viduals may show decreased ab ili ty to learn and remember new inforn1 ati on in the long tern1, other cogniti ve proces es were unaffected. Thus, while there may be neurophysiological and neurovascul ar effects of chronic marijuana use, some of these effects may be sil ent. Marijuana use has been shown to have negative psycho logical conseq uences, specifica ll y an increased ri sk of psychosi . It is poss ibl e that cannabino ids ' effects on dopam ine release contribute to the onset of psychosis. 17 A ystematic rev iew of 35 popu lation-based longitudinal stud ies concluded that individuals who had ever used marijuana had an increased risk of developing p ychosis later in life. 18 Furthermore, a dose-dependent relationship was observed w here heavier users had a further increased ri sk of psychosis (adj usted OR 1.41 , 95% CI 1.20- 1.65 vs. 2.09, 1.54-2.84 , res pectively) . Of course, a possible interpretat ion of these re ults is that an underl ying, undi agnosed psychotic disorder leads to cannabi s u e, which faci litates the di scovery of the pre-exi ting psychological illness. Simil arl y, the oft-c ited 'amot iva tional syndrome,' in which the sufferer is chronica ll y unprodu cti ve, a imless and unmoti va ted, is One study found that assoc iated with chronic marijuana use. indi viduals who have used marijuana a minimum of 5000 times were signifi cantl y less likely to graduate from co llege and less likely to earn more than $30 000 (US) per year. 19 However, like psychosis, thi s may be expl ained by the presence of many confounders inc luding pre-ex isting depression. Gruber et al. have recently published data indicating significant alterations in fronta l white matter tracts in chronic marijuana smokers. The authors suggest that these changes are associated with increased impulsivity, whi ch may contribute to the initiation of chroni c marijuana use or the inab ility to di scontinue use20

HEALTH PROMOTION Risk factors for marijuana use and abuse: Ri sk factors for marijuana use include male gender and age 18-25 , while risk fac tors for dependence, defi ned a a maladapti ve pattern of use despite negati ve effects, increa ed use, unsuccessfu l attempts at cessation and phys iologic withdrawa l, include ma le gender, age 12- 17 and absence of post-secondary edu cati on 4 Stinson et a l. 2 1 ha ve underscored that cannabi s abuse and dependence are genera lly phenomena of ado lescence and youn g adulthood, and onset of dependence after age 30 is rare. Stinson et al. 's results confirmed that, unlike w ith alcoho l (where ri sk of dependence persists for decades after first use) , there is a shorter developmenta l peri od of risk for cannabi s dependence. As such, there is a window of o pportunity in ea rl y ado lesce nce for the impl eme ntati on of preventi on and intervention programs, in order to have max imum impact. A pro pecti ve long itudinal study of a community sampl e (n = 302 1) aged 14-24 years in Munich, Gennany,22 found that 56% of all repeated cannabi s users (five times or more) still reported cannabi s use at 4-year fol low-up . At 10-yea r fo ll ow-up, thi s proportion had decreased onl y sli ghtl y to 46 .3%. Among youth who are repeated cannabi s u er , patterns of use remain table, and rates of cessation are low, until age 34. Such patterns suggest that preventi ve measures sho uld de lay first use and reduce the number of uses, as these factors appear cruc ial in the transition to persistent and dependent use of cannabis.22 A lthough males may have hi gher rates of marijuana use, Schepis et a l. 23 have suggested , based on results from a cross-sectional survey of Connecti cut ado lescents, that fe ma les may have a more rapid tran ition from initi al marijuana use to regul ar or dependent use. The

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authors also suggested that marijuana use was assoc iated, not surprisingly, with ri sk behaviour parti cipation (e.g. other substance abuse) and that partic ipati on in ex tracurri cular activities was protective agai nst marij uana use. A prospective cohort study of Swiss teenagers and youn g adu lts was performed to evaluate different lei sure time acti vities and the persons (e.g. partn er, friend, si bling) with who m the acti vities we re undertaken 24 The choice of compani ons for leisure act ivity was mo re important than the activity itse lf as a predi ctor of initi ati on and progressio n of cann abi s use, supporting the widespread view that peer influences are parti cul arl y important in you ng people's risk behaviour . This finding was rei nforced by data from the German study 18 cited above, in whi ch peer use of cannab is, stressful life events and alcohol depende nce predi cted long-term mariju ana use.

Treatment of marijuana use disorders: Despite public perceptio ns of marijuana as a relative ly innocuo us drug, exposu re. to ps yc ho ac ti ve ca nnabinoid s can indu ce st ro ng drug- seek mg behaviours; these are medi ated by increased dopamine release m the brain 's reward pathway.29 Abrupt w ithdrawa l of canna bm01ds after long-term ex posure can produce dysphoric effects, wh1.ch ~ay contribute to relapse. Although cannabis shares neurobwlog1cal features associated with de pe nd e nce o n o th e r dru gs , on ly approximatel y one-tenth of individuals who abuse cannabi S had ever rece ived treatment. 17 Psychosocial interventions, although effect1 ve in the short-term, often lead to long-term relapse, and the ava tlable beha vioural treatments are onl y modestly effective. As such, there IS a need to develop pharmaco logical intervention , and currently none have been va lidated throug h clinical trial s.25

Marijuana and tobacco: Health promotion for marijuana cessation is

As described above, cogniti ve impairments may not be fully reversible even I month after cessation of marijuana use. It re mains un clear if these findings refl ect long-term effects of marijuana, or si mpl y an impairment of baseline cogniti ve functioning in marijuana users. Nonetheless, cogniti ve impairments in marijuana users may result in poor treatment response,3째 particul arl y in light of the lack of motivation and increased impu lsivity that is assoc iated wi th c hro nic marijuana use. Studies have suggested that c ho linesterase inhibitors may ha ve a ro le in improving cann ab is- indu ced cognitive impairments, but these drugs have not yet been evaluated in humans for the treatment of marijuana dependence. Cogniti ve re habilitation has improved function an d treatment outcomes in individuals addi cted to oth er drugs. ofuoglu et al. have thu suggested that improving cogniti ve function may serve as an important treatment strategy for marijuana use disorders 2 6

pa rti c ul a rl y importa nt g ive n the hi gh co-m o rbidit y between mariju ana and tobacco use, and the potentiall y damag ing interact ion of these two ubstances on respiratory outcomes. Leatherdale, Hammond, Kaiserman et at.2 5 described results fro m a 2004 tobacco use survey of 20,000 yo un g adu lt Canad ians (aged 15-24). The rates of marijuana use were hi ghest among current tobacco smokers, and lowest a mong yo uth who had never smoked. Those who use marij uana are less likely to quit smoking (odds rati o 1.94); th ose who use marijuana dai ly are even less li ke ly to quit than th ose who have used at some point in the past 30 days 26 Thus, whil e marijuana use itself may or may not be assoc iated with an increased ri sk of lung cancer, marijuana use may secondaril y increase th e ri sk of lung cance r throug h its assoc iati o n with pe rsistent to bacco use . Conve rsely, through use of prospecti ve survey meth odology, Schaub et at.2째 found that nicotine use increases the ri sk for both the initiation and the progression of cann abi s use. The auth ors also repo rted that tobacco use remai ned hi gh even afte r reduction or cessati o n of cannabis use. Thus, there appea rs to be a bidirecti ona l ri sk between tobacco and marij uana use, with use of either substance increasing the likelihood of using the oth er. Clini cians should ask about marijuana hi story and take marijuana use into account when recommending tobacco smoki ng cessati on meas ures for th e ir patients, and vice ve rsa.

Mental health disorders and use of cannabis: A study of 884 1 Australian adults aged 18- 85 year found that participants wi th affecti ve disorders and anxiety di sorders were at increased ri sk of harmful drug use and drug dependence. 27 This corre lati on was parti cul arl y strong for you ng males, a group already identified ea rli er as hi g h-ri sk for ma rijuana dependence. Another stud y reportin g o n cannabis use disord ers and mood and a nxiety disorder co-morbidity showed th at bipolar diso rd ers, pa ni c disorder with ago raphobia, and generali zed anx iety disorder had th e stro ngest associa ti o ns wi th cann abis abuse and dependence. 17 Whi le th e directi o nality o f thi s assoc iati on re mains un clea r, one th eory is th at th e ex peri ence of untreated affective disorders and anxiety disorders may lead to se lfmedi cati on with psychoactive substances such a mariju ana. A uc h, it is important for hea lth practitioners to identi fy a nd treat und erl yi ng men tal hea lth conditi ons in a timely and effective manner. Indeed, there is evidence th at such practi ces can reduce ma rijua na use, as demonstrated by two ra ndomi zed controll ed tri als included in a systemati c rev iew.28 For exampl e, in a flu oxetin e treatment gro up, ca nn abi use decreased in patients with depression. In patients with psychoti c disorders, both olanza pine and ri sperid one treatment grou ps also reduced cannab is use. From a health system-level perspecti ve, overcoming th e treatment fragme ntati on between mental health and drug and alcohol serv ices wo uld mea n that the iss ue of comorbidity among clients (particularly yo un g peopl e) can be more adeq uately addressed.7

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Harm redu ction through use of va po uri zers : Given the widespread use of marij uana, th e increasing abuse a nd depende nce on this sub tance, and the paucity of effective treatment trateg ies, it is important to consider harm reducti on approaches to mitigate marijuana' potential adver e con eq uences. This pragmati c approach is parti cul arly com pelling given marijuana 's increasing use for medi cinal purpo es. Accord ing to resu lt from a 1998 Canadi an survey, medi ca l use of marij uana was less common than its recreati o nal use (2% ve rsu 7%),31 but thi picture may change in light of the shi ft ing legal la ndscape surrounding medic inal marijuana. Cann abinoids acti va te the arne neu rotra nsmitter pathways as e ndocannab inoids, prod uci ng effects ranging from a nalgesia to appetite stimulati o n to nausea reduction . They al o cau e a reduction of intraocul ar pressure, hence the usefulnes of ma riju ana in treating the ymptoms of g laucoma.32 The main challenge for the medi cal u e of cannab ino ids is the deve lopment of safe and effective methods of use th at lead to therapeutic be nefi t, without res piratory conseq ue nces o r oth er adverse effects. Ea rl eyw ine a nd Ba rnw e ll 11 ha ve desc ribed th e use of vapo uri zers among marij uana smokers : vapo uri zers release active cann a bino ids but not smoke o r carcinogens a sociated with combu tion . The use of a va pouri zer is assoc iated with decreased respiratory sympto ms, a nd this effect increases with th e amount of cannab is used. Furthe m1o re, vapourizer can deliver ca nnabi s with no carci nogeni c potenti al. This has importa nt implications for safe use of. medi ca l mariju ana as we ll as harm reduction among recreatwn al smokers. In o ne study, twenty frequent cannabi s users who reported respiratory complaints were eva luated befo re and after the use of a vapourizer for one month 33 Among participa nts who did not develop a res piratory illness during th e trial , there was a significant improvement in respiratory symptoms a nd FVC and a non- ignifi cant improvement in FEY I . These improvements c~u ld be even more meaningful in cannabi s users who al o smoke tobacco The . authors c?ncluded, given . th ese. ~eani.n gfu l recovery of resptratory functiOn, that a randomi zed cltnt ca l tn al of the cannabi s

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' vapourizer should be performed. The va pouri zer has potential for the administration of medical cannabis and as a harm reduction technique, particularly for those unin terested in marijuana cessation or who have been chronic, heavy users.

CONCLUSION A lthough the prevalence of marijuana use has not changed sign ificant ly in recent years, the higher cannabinoid content of current plants may be contributing to the observed increase in rates of dependence in ado lescents. Both phenomena - increased dose of psychoactive drug, and increased rates of serious dependence - have catalyzed more research into the long-term neuropsychi atric effects of marijuana use. Long-term marijuana use is associated with an increased risk of psychosi s and 'amotivational syndrome '. However, the direction of causation remains unclear, not least because the risk of marijuana dependence during ado lescence is clearly increased by co-morbid psychiatric di sorders and has been characterized as a fonn of 'self- medication '. Marijuana is also associated with specifi c longterm cogn itive abnormalities; the possibility of reverse causation seems remote for these findings, but further research is needed. Marijuana has immediate adverse effects on respiratory mucosa simi lar to tobacco; however, evidence for chronic respiratory disease related to marijuana is weak. For lung cancer, imilarly, heavy marijuana use produces metaplastic changes but there is no compelling evidence for an association w ith clinical di sease. The contradictory evidence for both conditions may reflect differences in the chemistry and cellular effects of marijuana as contrasted with tobacco, as well as the high frequency of joint exposure. In that latter regard, the more significant risk for respiratory illness, including malignancy, may arise from the strong association of tobacco and marijuana use, and the reduced likelihood of smoking cessation in the presence of joint dependence. From the standpoint of health promotion , we can draw a number of key conclusions. Primary prevention of marijuana dependence wi ll require health education targeting pre-adolescence. The preva lence of comorbid psychiatric disorders in dependent adolescents highlights the need for an integrative approach to treatment and secondary prevention . Awareness of the conjoint use of tobacco and marijuana is important for clinicians seeking to promote smoking cessation. Lastly, vapourizers have the advantage of miti gating respiratory ri sk and may serve as an effective harm reduction strategy fo r those who are chronica lly dependent or using cannabinoids for clini ca l indications.

REFERENCES I. Mehra R, Moore BA, Crothers K, Tetrault J, Fiellin DA. The assoc iation between marijuana smoki ng and lung cancer: a systemati c rev iew. Arch Intern Med. 2006 Jul 10; 166( 13): 13 59-67 . 2. Hea lth Canada. Youth Smoki ng Survey 2006-2007 . http://www.hcsc. gc. ca / h c -p s / t o bac- ta bac / r esea r e b - r ec h e rc h e /s t a tl _ s ur veysondage_2006-2007/tabl e- 12-eng .php. 2008 Dec 22. 3. Hea lth Canada. Canadian Alcohol and Drug Use Monitoring Survey : Summary of Resu lts For 2009. bttp -ljwww bc-sc gc ca!bc-ps/drugsdrogues/statl 2009/summary-sommai re-eng pbp#cann abis. 20 I 0 Jun 30. 4. Kandel D, Chen K, Warner LA, et al. Prevalence and demographic correlates of symptoms of last yea r dependence on alcohol, nicotine, marijuana and cocaine in the U.S. population . Drug Alcohol Depend 1997 ; 44 :11. 5. Sofuoglu M, Sugarman DE, Carroll KM . Cognitive functi on as an e mergi ng treat me nt target for mariju a na a ddi ctio n. Ex p C lin Psycboph armacol. 20 10 Apr; 18(2): I 09-19. 6. Compton WM, Grant BF, Co lli ver JD, Glantz MD, Stinson FS. Prevalence of marijuana use disorders in the United States: 199 1-1 992 and 200 1-2002. JAMA. 2004 May 5;291 ( 17):2114-21 . 7. Vandrey R, Haney M. Pharmacotherapy for ca nnabi s dependence: bow close are we? CNS Drugs. 2009;23(7):543-53 .

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8. Raphae l B, Woodin g S, Stevens G, Connor J. Comorbidity: cannabis and co mplexity. J Psycbiatr Pract. 2005 May; II (3): 161-76. 9. Tetrault JM , Crothers K, Moore BA , et al. Effects of marijuana moking on pulmonary fun ction and respiratory comp lications: a systematic rev iew. Arch Intern Med 2007 ; 167(3): 22 1-228 . I 0. Wu TC, Tashkin DP, Djahed B, Rose JE . Pulmonary haza rds of smoking marijuana as compared with tobacco. N Engl J Med 1988 ; 3 18: 347 . II . Earl eywi ne M, Barnwell SS. Decreased respiratory symptoms in cannabi s u ers who vapori ze. Harm Reduct J. 2007 Apr 16; 4: II . 12. Ha ll W, Chri stie M, Currow D. Cann ab inoi ds and cancer: ca usation , remediation , and pal liation. Lancet Oncol. 2005 Jan;6( I ):35-42 . 13. Melamede R. Can nabis and tobacco smoke are not equal ly carc inogeni c. Harm Reduct J. 2005 Oct 18;2:2 1. 14. Guzman M. Cann ab in oids: potenti al anti cancer agents. Nat Rev Cancer. 2003 Oct;3( 10):745-55 . IS. Bolla Kl , Eldreth DA, Matochik JA, Cadet J L. Ne ural substrates of faulty dec ision-making in abstinent marijuana users. Neuroimage. 2005 ; 26(2): 480-492 . 16. Heming RJ , Better WE, Tate K, Cadet JL. Cerebrovascu lar perfusion in marijuana users during a month of monitored abstin ence. Ne uro logy. 2005 ; 64(3): 488-493 . 17. Fergusson DM , Pou lton R, Smith PF, Boden JM. Cannabis and psychosis. BMJ . 2006; 332(7534): 172-175. 18. Moore TH , Zammit S, Lingford-Hughes A, Barnes TR, Jones PB, Burke M, Lew is G. Cannabis use and ri sk of psychotic or affective mental health outcomes: a ystemati c rev iew. Lancet. 2007 ; 370(9584) : 3 19-328. 19. Gruber AJ , Pope HG, Hudson Jl, Yurgelun-Todd D. Attri butes of longtenn heavy cann abis users: a case-control study. Psycho! Med. 2003 ; 33(8) : 14 15-1422. 20. Gruber SA, Si lveri MM , Dahl gren MK, Yurgelun-Todd D. Why so impu lsive? White matter alterations are associated with impu lsivity in chronic marij uana smokers. Ex p C lin Psychoph armaco l. 20 11 Jun ; 19(3): 23 1-42 . 2 1. Stinson FS, Ruan W J, Pi ckerin g R, Grant BF. Cannab is use di sorders in the USA : preva lence, correlates and co-morbidity. Psycho! Med . 2006 Oct;36( 10): 1447-60. 22. Perkoni gg A, Goodw in RD, Fiedl er A, Behrendt S, Beesdo K, Lieb R, Wittcben HU. The natural course of cannabis use, abuse and dependence during the first decades o f life. Addiction. 2008 Mar; I 03(3):439-49. 23. Schepis TS, Desa i RA , Cavall o DA , Smith AE, McFetridge A, Liss TB, Potenza MN , Kri shnan -Sarin S. Gender differences in ado lescent marijuana use and associated psychosocia l characteri stics. J Addict Med 20 11 ;5: 65- 73. 24. Schaub M, Gme l G, Annaheim B, Muell er M, Schwappacb D. Leisure time acti viti es that predict initiati on, progre ion and red uction of cannabis use: A prospective, population-based panel survey. Drug Alcohol Rev 20 10;29;378- 384. 25. Leatherdale ST, Hamm ond DG , Kaiserman M, Ahmed R. Marijuana and tobacco use among young ad ults in Canada: are they smoki ng what we think they are smok in g? Cancer Causes Contro l. 2007 May; 18(4) :39 1-7. 26. Ford DE, Vu HT, Anthony JC. Marijuana use and ce ati on of tobacco smoki ng in adults from a communi ty sampl e. Drug A lcohol Depend. 2002 Aug I ;67(3):243-8. 27. Li ang W, Chikritzhs T, Lenton S. Addicti on. 20 11 Jun ; l 06(6): 11 26-34. Affective di sorders and anxiety di sorders predi ct the ri sk of drug harm ful use and dependence. 28. Baker AL, Hides L, Luhman Dl. Treatment of cann abi use among people with psychotic or depressive di sorders: a ystemati c review. J C lio Psychi atry 20 10;7 1:247- 54. 29. Vandrey R, Haney M. Pharmacotherapy fo r cannabi dependence: bow close are we? CNS Drugs. 2009;23(7):543-53 . 30. So fu oglu M, Sugarman DE, Carroll KM . Cogniti ve fun ction as an e merging tr eatme nt target fo r marijuana ad di ction. Exp C lin Psycbopharrnaco l. 20 I 0 Apr; 18(2): I 09- 19. 3 1. Hall W, Chri stie M, Currow D. Ca nnabino ids an d cancer: causati on remedi ation, and pal liation. Lancet Oncol. 2005 Jan;6( 1):35-42. ' End ocannab ino ids in the reti na: from marijuana to 32 . Yazu lla S. neuroprotection . Prog Ret in Eye Res. 2008; 27(5): 501-526 . 33. Van Dam NT, Earl eywi ne M. Pulmonary function in cannabis users: Support for a c lini cal trial of the vapo uri zer. lnt 1 Drug Policy. 20 10 Nov· 2 1(6):5 11-3. ,

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An Interview with Dr. David Leasa Lauren Sham (Meds 2014}, Abdu l Naeem (Meds 2014}, Joyce TW Cheung (Meds 2013}

ln disaster management, where eti ologie of disease can be unknown and every second is of the essence, a wellfunctioning inte nsive care unit (LCU) is paramo unt. The SARS (Severe Acute Respi ratory Syndrome) outbreak in 2003 highlighted the importance of efficiency in meeting the challenges of medi cal urgencies. In an area where resources are limited, cri ses exacerbate c hall enges with staffi ng sho rtages and bed reducti ons, compou nd ed by disease transmission w ithin th e lCU , staff quarantine, emotional stre , and a constant influx of criti ca ll y ill patients I. However, the 2003 outbreak also prese nted itself as an opportunity to improve criti cal care delivery, with respect to implementing better infecti on control measures, developing software for handheld devices specific for SARS, and hav ing regul ar teleconference call s to both combat the feelings of iso latio n and increase information dissemination on this unknown illness 1• One needs passion and proficiency in handling "acute medi ca l problems where problems often come in undefi ned," says Dr. David Leasa, a London, Ontario based ICU ph ys ician.

T

Dr. Leasa was born and rai ed in Waterloo, Ontario, and studied Phys iology and Pharmaco logy at the University of Western Ontario (UWO). He continued hi s studi es at UWO in medicine and completed hi s internal medicine residency there as we ll. After specializi ng in Respirology and C riti ca l Care he moved to Seattle, Washington to pursue a year of resea rch. He moved back to Canada, wo rked at St. Joseph's Hospita l and later moved to University Ho pita! where he is currentl y working as an I U physician and Respirologist. When not in the hosp ita l, Dr. Leasa e nj oys being outdoors. He likes to ki (even hope for a retirement in Whi stler!), swim , and run - all act ivities he fee ls help him lead a balanced healthy li fe.

ea rli er, wi th th e ai m of preve nting ICU admi ssio ns. He also has a week in Exte nd ed ICU (E ICU) where he provides care for patients needing prolonged ventilator care for greater than three weeks. In additi on to ICU, he spends o ne week every 2 months on the Respirology service taking consult . Finally, he also has a chest clinic that is evolving into providing care for chro nica ll y venti lated pati ents. In the ICU, Dr. Leasa empha izes, " You need to have a team of peo ple put forth what is the best management for that individual." This team approach reflects th e dynamics on the wards. ln the ICU, all the physicia ns come fro m different pecialties but have added skills in criti cal care. (Criti cal care is an additi o nal two-year RCPSC subspecialty after hav ing completed a base specia lty.) Dr. Leasa admits that a he gets ol der, ICU may be too demanding (especiall y ni g hts!) and that it wi ll be nice to be ab le to fa ll back on his o utpati ent pract ice. He enjoys chatting with hi s pati e nts and meeting people in this setting. This prov ides continuity with pati ents who get very ill initiall y, but he can follow and see them in a different etting as th ey recover - see th ei r per ona li ty and who they are as indi viduals, o mething he cannot alway experi ence in the !CU. However, hi s pass io n has a lways been intensive care. He e nj oys managing a nd problem- o lvin g acute care Res pirology ca es in th e ICU , fro m pneum onia to acute re piratory distress syndro me (ARDS ), to broncho copies and pleural effu io ns.

Being a n ICU phy s ician and a Respirol ogist is demandi ng. Dr. Leasa leads a very act ive and busy work life. He tends to have a week of " days" ( 12 ho ur shifts) in I U, alternatin g with a week of " ni ghts," and is on-ca ll some weeke nds. During ni ghts, a new initi ative is in place where the ICU staff has c riti ca l care ou treach . Qualified ICU ph ys icia ns extend their expe rti se to o th er depa rtm ents if th ey fee l a patie nt might end up in the ICU . By extendin g their services outside of the ir usual bo und ari es, th ey are ass isting patients

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Th e practice of b ot h I CU and Respirology has led Dr. Lea a to hi s interest in lo ng-tern1 mechani cal ventilat ion - he is known as th e " ho me ve nti latio n doctor. " He i presently invo lved in an initiative to provide care for stable chroni cally venti lated patients by moving the m from the ICU environment to othe r community venues, inc ludin g home if pos ibl e. Dr. Leasa believes that "to do it safely, prope rl y and effecti ve ly, we need to do it using a systems approach." He wou ld want to not on ly prevent pati e nts from e ndin g up in the ICU agai n but also improve the ir overa ll qua lity of life through care at ho me or in the community. At the momen t, he is tty ing to advocate that thi s initiative needs the proper fundin g: if we can prevent these patients from us ing ICU beds a nd s hift th ese reso urces to the community, there wou ld be benefits for all. Hi s vision for this project Involves deve lopmg a community-ba ed


mode l for the region of South western Ontario. Currentl y there are more than 180 patients w ho are on both non-inva ive and invasive ve ntil atio n in our catchment area. Ventilator technology has changed dramaticall y over the past decade including its ease of use and increasing app lication using a noninvasive mask interface . However, several hurdl es rema in inc luding cost, need for trained communi ty careproviders and for patients/famil y members to be ed ucated and empowered. Dr. Leasa is currentl y trying to create a coordinated system of people who understand the complicated nature of the care for these chroni call y ven til ated patients. One important task i to identify and support those pati ents for whom chroni c ventilato r care at home improves qua lity of life. Importantl y, this needs to be done in a way that coordi nates all caregivers ' skill s so that pati ents do not end up back in the ho pital. There are man y patients that can bene fit from this type of technology (es peci a ll y those wit h chroni c neuromuscu lar di sease), but in order to do thi s safe ly and effecti vely, a preplanned system needs to be in place, and thi s is what Dr. Leasa is trying to help e tabli h. The future of critica l care holds a plethora of possibi liti es, but also many difficult ethica l issues. Because patients in the ICU are often amongst the sickest people in the hospita l, the difficult issue of death and dying often arises, and proves to be a challenge for both families and the JCU team. Dr. Leasa believe that an important step in improving care for patients in the ICU lies in education on the taboo subj ect of dying. Due to adva nces in med ical technology, patients can be kept a li ve fo r longer than their bodies would natura ll y be ab le to ustain . Difficult issues arise when one has to cons ider the quality of life for a pati ent who is unconscious and unab le to survive without the aid of sophisticated machinery. Dr. Leasa is not one unfamiliar with making difficult decisions. Recentl y, he bad to sit down with the fa mil y of a 95 year o ld man who bad a myriad of comorbiditi es, none of which were easy to manage. As medi cal students we learn: " primum non nocere," or "first do no harm. " You would think that everyone would want to give this man as comfortabl e a death as possibl e. However, hi s fa mily expressed that he wanted to li ve unti l he was I 04, and wanted everything possib le done for him , from intubation to chest compressions. Perhaps it was guilt fro m neglect in previous fa mil y confl icts, or a just desperatio n to cling onto any semblance of life possible, but these situations are not always as clear as they appear, neither to the family nor to the clini cian.

pl anning for surges. He notes, " If yo u stop criti ca l care, yo u stop everything. Everything starts to back up. " He also thi nks we need more di scussions on the ethical use of resources: not ju t at the level of the indi vidua l, but on a soc ieta l level. He poses the question , " If we had SA RS again, and we ran out of ve ntil ator and ICU beds what wo uld we do? Would we use a predetennined algo rithm to see who gets a ve ntil ator and who does not?" He acknowledges that it is difficult to have these di scus ions, but working thro ugh these scenarios is necessary. After go ing through SARS , politic ians fin all y understood it, even ex pressing th at " SARS was good for criti ca l ca re - it created outreach teams, put more nurses into the system , and looked at what 's go ing on with respect to reso urce - what they are, and where they are." Dr. Leasa be lieve that the general public needs to be better educated on the purpose of the ICU, but a lso that it has its limits. He and hi s colleagues spend a lot of their time di scuss ing what critical care reso urces can and cannot do. Edu cation of the ge nera l public becomes increasing ly important as the vo lume in the ICU increases. With the current adva nce in li fe support sy tems we are abl e to extend li fe that previously wo uld have ended . Thi s leads to new cha ll enges. He wants peo ple to understand that we cannot cure everything, and we cannot always delay death. Many times patients are chroni ca ll y ill at the end of their li ves and are in a proce s of dyi ng. Shou ld ICU care and a ventilator be part of that death process? There is still a gap between what patients and or the ir fam ili es ex pect and w hat our current medi ca l technol ogy can ethicall y and reasonab ly deli ve r. Dr. Leasa is hoping we can bring the two c loser together.

REFERENCES I. Communi cati on in the Toronto criti ca l ca re communi ty: important le son learned during SARS. C hri stopher M Booth and Thomas E Stewart . Crit Ca re. 2003 ; 7(6):405-406. http://www. ncbi.nlm .nih .gov/pm c/arti c les/ PM C37438 1/ 2. http ://www. hea lth .gov.on .ca/e ng l ish/prov iders/prog ram/cr i tic a I_ ca re/ cct_strategy. html

So how do we open up and begin talking about these diffi cult issues? Dr. Leasa believes the family unit is critical in these di scussions. The difficulty in talking about the deteriorating health of a loved one is trying to figure out what the patient would have wanted for him or herself. He recall s some fa mili e who have not seen or talked to Dad in ten years but think that prolonging care is what he would want. As criti cal care has bettered itself with improved communication, so too wou ld families. Dr. Leasa lives out this philosophy, which was inspired by the mentors he has had over the years: "The phys ic ians I learn ed a lot from were those who sat with patients and talked honestly to them," he said, noting that they didn 't keep a di stance but instead liked to understand the person they were treating. As past-president of the Canadian Criti ca l Care Society (CCCS), Dr. Leasa has participated in many activities to enhance the quality of care in ICUs across the country. The CCCS has guidelines on how to assist in difficult issues at the bedside, as well as advocate for improvement of patient and fa mil y experience in the ICU. He notes that critical care has had its shake ups, including the SARS outbreak which was an eye opener for governments and health care professionals alike, but they learned that critical care had to be done as a collective. He believes that they have been doing a good j ob in Ontario2 in dea ling with increased occupancies and having clear

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A lung mass and digital clubbing in a young woman Julie Lebert (Meds 2013), Joyce TW Cheung (Meds 2013) Faculty Reviewers: Dr. David Leasa, Dr. S. Nelson

nflammatory myofibroblastic tumo urs (IMT), also kn ow n as plasma cell granul omas or inflammatory pseudotum ours, are the most common paediatric primary lung tumours. 1 Pati ents present at a mea n age of 9.7 yea rs, maki ng it an unusual adult di agnosis 2 IMTs are extremely rare, acco untin g for onl y 0.05% of all th orac ic procedures 3 !MT bas traditi onall y been class ified as a beni gn tum our, but recent studi e suggest loca ll y aggressive behavio ur an d ma li g na nt pote nti a14 Radi og ra phi ca ll y, it is impos sib le to differenti ate between an !MT and a malignant mass, 4 as the presentation of th e tumo urs are hi ghl y vari able. IMT may be cysti c or homogeneous, endobronchial or parenchyma1. 1 It is th ought to result as an inflammatory reaction to an infecti on or an underl ying low grade mali gnancy. Patie nts usuall y prese nt with loca l mass effects with or without systemic features such as fever, weight loss, microcytic hypochrom ic anemia, polyclo nal hyperglobulinemi a, elevated ES R, and hype rtrophi c osteoarthropathy (HOA) 2 •4 Due to its vari ab le natural history, compl ete surgical excision is the treatment of choice.3

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CASE REPORT A 24-year-old female presented to o ur institution with a fo ur-month history of left sided pleuritic c hest pain . The pati ent had a hi story of hypochromic microcytic anemi a and was currentl y taki ng oral co ntrace pti ve pill s a nd iro n s uppl e me nts. Upon ph ys ica l examinati on, a review of systems revea led that she had a no nproducti ve co ugh, dre nching ni ght sweats, fatigue a nd had lost I 0 po unds. She a lso reported joint pai n and mo rnin g stiffn ess, predomina ntl y in vo lving he r wrists, knees and ankl es. The pati e nt had recentl y fini shed a ten-day co urse of a ntibi oti cs with no symptomati c improveme nt. She was a non-s moker with occasional marijua na a nd alco hol use. Her family hi tory wa negati ve for mali gnan cy, but her brothe r had asthm a. The pati ent had te ndem es to palpati o n ove r late ral c hest wa ll on ph ys ica l examinati on. Bilateral clubbing of th e di g its wa noted . Laboratory in vesti gati o ns revea led hypochro mic mic rocyti c anaemia (hae moglobin leve l of 80 g! L, a mea n corpu c ul ar vo lume of 77 . 1 fL , microcytic hypochromas ia). Chest plain fi lm showed a mass- like conso lidatio n in the left lower lobe with enla rge ment of th e left hilum . Computed tomograph y (CT) showed a heterogeneo us soft ti ss ue rn a ex tendin g from th e lateral che t wa ll to th e inferi or aspect of the left hilum . No cav itati o n or cha racteristic ca lci fi catio n was identified. Small blood vessels we re seen within th e les ion, but did not have th e appea rance of norm al lung vesse ls. The mass ex tended centrall y to contact the inferior aspect of th e left hilum . No lymph node, c hest wa ll in vas io n o r rib destru cti on we re identified . Ex pl oratory left th o racoto my with enucleation of the tumo ur was perform ed and an intra-operative frozen section of tumo ur (3 .2 x 2.0 x 1.5 em) showed hi stology consistent with beni gn spindle cell

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tum o ur. Fo ll ow ing this procedure, the tumour increased in size from 4.1 e m to 5.4 em over a six mo nth peri od. Thi s recurrence of the tumour suggested locall y aggress ive behav iour; and it was decided to perfo rm a left pneumo nectomy. Surg ica l patho logy showed no overt cytoli c atypic, however vascul ar invasion and invo lvement of the di aphragmatic ti ssue were evide nt. Clea r resecti o n marg ins were ac hi eved in th e pneumonectomy and resecti on of di aphragm. Adjuvant c hemothera py or radi at io n was not recomme nded . DISCUSSION

Clinical manifestations Infla mmatory myofibroblastic tumour (I_MT) is a rare tumo ur that is mo t commonl y a ociated with th e paedi atri c po pulation . Numerous studi es, however, bas shown that IMT can affect people of any age and eq uall y affects both gender .2.4 It i also important to note that IMT can occur thro ugho ut tb e body. In a review of 44 pati ents with IMT, Ko ach et al. reported IMT occurring in the li ver, gallbladder, orbit, medi astinum, neck soft tissue, trac hea, bowel , brain and others. 4 The orga n wi th th e hi ghest frequency of di agno is is th e lung (9 of the 44 pati ents) 4 The presentati on of IMT depends on the locati o n of the tumour and i influenced by local mass effects fro m the tumour size. 4 IMT can present w ith a variety of symptoms, both syste mic and localized, uch as anaemia, weight loss, feve r, pain, and mas .2 For example, in thi s case, th e patient prese nted with pleuriti c chest pain . The lung is th e most common locatio n of this neoplasm but has been repo rted to present with ex trapulmonary symptoms . There have onl y been a small number of case reports where hypertrophic osteoarthropathy (HOA) was ob erved .5· 6 •7 Furthermore, these cases occurred in children with no reported ad ult cases with HOA . The etiol ogy o f HOA in assoc iation w ith IMT of the lung is unknown .5

Pathology Infla mmatory myo fibrobl astic tumours pathologically consist of myo fibrobl a tic spindle cell s with a n inflammatory ce ll infiltrate.5 The appea rance of IMT under microscopic examination is variable both betwee n th e different site of occurre nce and between patients with tumours in th e same location .4 The etiology of IMT is still under debate and current opini on is changing as new information, especia ll y genetic analys i of the tum our cell s, comes avai lab le. It was initia ll y proposed that IMT arises from uncontrolled, excessive immune response to ti ssue injury (most likely from infection); however, more recent studi es suggest that it mi ght in fact be a true mali gnancy.4•8 Thi s is supported by reports of distin ct mutations in the cell s of th ese tumo urs a nd by the tendency for local recurre nce and invasion , distant metastas is a nd pote ntially sarcom atous degeneration .3.4.S

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Diagnosis A diagnosi s of IMT impossible to determine c linically as it is genera lly a di agnosis of exclusion. Upon imaging, a mass wi ll typically be identified ; however si nce IMTs occur with a wide range of radiol ogical characteri stics, imag ing does not often contribute to the diagnosis 9 Radiologica l reports on IMT, show that these tumours can be cystic or homogenous, endobronchial or parenchymal, and with or without clear margins.9 These qualities make IMT difficult to distingui sh fro m infectious or ma lignant patho logies. 4路9 Furthermore, biopsy of these les ions rarely results in a conc lusive diagnos is, as IMT can mimic many other patho logies such as fibrous hi stiocytoma, leiomyosarcoma or fibrom atosis.2 A confident diagno is can thus only be made fo llowi ng surgical resection and pathological anal ysis of the mass .s

8. van den Heuvel, D.A.; Keijsers, R.G .; van Es, H. W.; Bootsma, G.P.; de Bruin, P.C.; Schra mel, F.M.; van Heesew ijk, J.P. In vas ive infl amm atory myo fibroblasti c tumour of the lung. JO URN A L 2009; 4(7): 923 -926. .K. 9. Rasa lkar, D.D.; Chu , W. .W. ; To, K.F.; C heng, F.W.T. ; Li , Radi olog ica l appea rance of infl ammatory myo fibrobl asti c tum o ur. Pedi atri c Blood & Ca ncer. 20 I 0 ; 54: I 029-103 1.

Treatment There are several treatment options to consider after IMT is diagnosed. The first line treatment is surgical exci ion since IMTs have the potential to local recur, be loca lly invas ive, and occasionall y metastasize. Other suggested options include NSA IDs, steroids, radiation, chemotherapy and observation only. In a retrospecti ve study, 25 patients had complete resecti on of the tumour.3 The 30-day post-operative mortality was 4% and morbidi ty was 8%. 3 The 10-year survi va l was 89%, with one patient's death due to extensive sarcomatous recurrence 2 years post surgery.3 This study demonstrates that IMT has an exce llent prognosis with compl ete surgical excision, however must still be considered a malignancy wi th the potential to have di stant metastasis, local recurrence and sarcomatous degeneration .3 While surgery has shown po itive results in patient cure rates, the natural hi story of IMT has not been well studied 4 In a case series, it was noted that local recurrence occurred in 8% of patients where resection was attempted 4 Local recurrences tended to occur where complete resection of the tumour was not possible or where radiation or chemotherapy was not received 4

CONCLUSIONS IMT is more common in the paediatric population and rare in adu lts. However, it should be considered on the differential diagnosis when a mass presents in a non-smoking adult. 8

REFERENCES I . Chen, C.-K. ; Jan, C-1. ; Tsai , J.-S .; Huan g, H.-C.; Chen, P.-R.; Lin, Y. -S. ; Chen, C.-Y. ; Fang, H- Y. lnfl ammatory myofibrob lastic tumor of the lun g a case report. Journal of Cardiothoracic Surgery. 20 I 0; 5: 55-58. 2. Coffin, C.M.; Watterson, J. ; Priest, J.R.; Dehner, L. P. Extrapulmonary in fl ammatory myofibrob lasti c tum or (Inflammatory Pseudotum or). The Ameri can Journal of Surgical Pathology. 1995 ; 19(8): 859-872. 3. Fabre, D.; Fade l, E.; Singhal, S.; de Montpreville, V.; Mussot, S.; Mercier, 0. ; Chataigner, 0 .; Dartevell e, P.G. Com pl ete re ection of pulmonary inflammatory pseudotum ors has exce llent long-term progno is. General Thoracic Su rgery. 2008; 137(2): 435-440. 4. Kovach, S.J .; Fischer, A.C. ; Katzman, P.J .; Sall oum, R.M. Ettinghausen, S.E.; Madeb, R.; Koniari s, L.G . Infl ammatory Myofibrob lastic Tumors. Journal of Surgica l Oncology. 2006; 94: 385-391. 5. Pi chl er, G. ; Thalhammer, G .; Muntean, W.; Zach, M.S. Arthralg ia and di g ita l c lubb ing in a child : hype rtro phi c osteoa rthropath y wi th Scandinavian Journa l of. inflammatory pseudotumour of the lun g. Rheumatology. 2004; 33: 189-1 9 1. 6. Mas Esell es, F.; Andres, V. ; Vallcanera, A. ; Muro, D.; Co rtina, H. Pl asma cell granuloma of the lung in childhood: atypica l radiologic findin gs and associati on w ith hypertrophic osteoarthropathy. Pedi atric Radi ology. 1995 ; 25: 369-372 . 7. Mikou, N .; Balafrej, A. Pulondary fibro-xanthogranuloma associated with renal amyloidosis in a 5-year-old child . Arch Fr Prediatr. 1993 ; 50: 577-579.

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The economics of health and healthcare: a primer for the medical student Hang Shi (Meds 2013) Faculty Reviewer : Dr. Greg Zaric M.ASc, MS, Ph.D.

he Canadi an medi ca l tud ent, much like the Ca nadi a n publi c, is proud of its healthca re system but believes it is in need of e n ous refo rm . 1 The perceptio n is o ften that cost are increasing to unsustainab le levels, with th e co nundrum th at th e y tern still doe not deli ver a much a it hould, to as many as it should, or in a time ly enough fas hi o n 2 In a 2011 national survey, only 5% graded the hea lthcare y tern a excellent. However, less th an a third of a ll res pondents be li eved they had a strong understanding of how the healthca re ystem worked 3 How ca n one properl y rate a syste m th ey do not understand? While medi ca l students have a bas ic practi cal understandin g of th e medi ca l system, th ey are found lackin g w hen it co mes to th e eco nomi c theorie and princ iples th at govern hea lthca re.4 Thi s i not surpri sing g ive n th e very limited tim e th at ca n be allocated out of packed medi ca l curri culums 5 The concern neverthe less re ma ins th at medi cal stud ents may be un equipped and unprepared for the ir future rol e in hea lthcare reso urce a ll oca tio n a nd ma nage me nt. Witho ut a n appreciati o n o f some bas ic tenet of hea lthca re economi cs, hav ing a health y discussion, takin g a positi on, and making a we ll-in fo rm ed deci ion on issues o f hea lthca re system will be diffi cult. The purpose of this primer is to introduce to th e med ical student th e most funda menta l economi c co ncepts and how they are pertinent to healthcare. Ultimate ly, it will be up to th e students th emselves to buttress th e ir kn ow ledge in thi increas ing ly important subj ect area ; thi s editori al can onl y hope to whet th e pa late just e no ugh to enco urage furth er ex pl orati o n.

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HEALTH CARE IS A SCARCE GOOD The fund amenta l probl em th at unde rlin es th e study o f economi cs is ba ed on the s imple prem i e th at reso urce are finite w hil e hum an needs are infinite 6 When thinkin g abo ut a tang ibl e good uch a fossil fu e ls, the idea is easy to grasp. Everyo ne wa nt an unlimited supp ly of fossil fu e ls to powe r th e ir ge nerators and run th e ir machines. However beca u e thi re o urce i ca rce, there need to be a system that decides the a ll ocati on: name ly wh o gets it and how much they can get. Economists co ncern the mselves over the best way thi s a ll ocation shou ld be made, and a k themse lves how thi a ll ocati on ca n be th e mo t effi c ient while at the same time th e most equitabl e. When it co mes to any good produ ced in th e economy, even one as co mplex as healthca re, the fundam enta l proble m sti ll rema ins. The produ cti on of healthca re require th e mu lti tud e o f ra w materia ls and suppli es required for equipment and fac ilities. In additi on, it requires th e time and train ing of healthca re wo rker .1 All of th ese, inc ludin g time, are ca rce resources. Indi vidua ls sell th e ir time for wages and will even re fu se work and wage if it " isn' t worth th e ir time." Peopl e view the ir time as a va lua ble resource th at if used for work, can no longer be used for other acti viti e such as le isure.6 In much the arne way, once scarce reso urces a re devoted to the production of

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healthcare, they can no lo nger be used in the production of othe r valuab le goods. Each joul e of energy used to power a Magnetic Resonance Imaging ( MRI ) mac hine is one that cou ld have been used to power a school. Eac h year tra ining one doctor cou ld have been used to train several economi sts. (It takes more resources to train a doctor th an an economi st). One aspect of macroeconomic theo ry tries to determine how a nati on's scarce resources should be best a llocated between its variou secto rs. When po licymake r decide on more MRJ s and increasing the number of residency spot , it mea ns we have to g ive up more of something e lse. Cons ider the foll owin g : Canada 's Gross Domestic Product (GDP) has increased an ave rage of 1.7% ann ua ll y o ve r the last decade.8 GDP i a measure th at adds up a ll the goods and services that an eco nomy produces per year. This indicates that on average, the Canadi an economy g rew by I .7% each yea r o ver the last decade. The healthcare sector has increased by an a erage o f 4.7% annua ll y over a s imilar peri od.9 If the entire eco no my is viewed as a pi e, then this mea n that w hile each year the pie get a little bigger, it has not been able to keep up with th e increasing s ize of the hea lthcare lice. If more of the pie is be ing di tributed to healthcare, th en less is left ove r fo r va ri ou sectors such as educat io n agri culture, or hi g h-tech indu try. Everyone rea li ze th at healthcare i ~ important. The diffi cult questi on is how importa nt. If fo r example, we va lue an additi ona l unit of hea lth ca re more than an addit iona l unit of national de fe nse, th en fo regoing more de fen e fo r increased pendin g o n hea lthca re benefit oc iety. If o ur va lue we re reversed then additi onal spending on hea lth care wo uld res ult in Ie s sociai bene fit. Deciding how muc h a nati on should spend o n hea lthcare is a diffi cult questi o n beca use it ca ll into questi on o ur va lue and forces u to a k how much we va lue hea lthca re over everything e l e.

ECONOM ICS A A SOC I AL SCIENCE: UNDERSTANDING THE POWER OF INCENTIVES While th e fi e ld o f modem economi cs relies on a e mpirical-based approach with tati stical analys is, the fi e ld has it roots in the oc ial sc iences. At its hea11 lies th e desire to understand the decisio n makin g of individua l in the ir production or consumption of goods o r erv1 ces 6 Econo mi sts assum e that decision makers are ratio na l and make cho ices that be t furth er their own ends. By under tanding the mcenll ves th at indi vid uals fa ce and how these then motivate a parti cul ar course of acti on, economists ca n predict and the re fore mode l the outcomes.6.7 . . W hen thi s mode ling i app lied on a larger ca le to gro up of md1V1dual s, economists hope to better understand and predict the consequences 111 th e eco nomy based on changi ng incentives. For example, . w hen it comes to physicians deciding the ir location for pract.. ce, 1ncen t1 ves ~lay a hug~ ro le .7路 10 As recently as 2006, 1 in 9 phys1c 1ans educated 111 a anad1a n med1 ca l schoo l practiced in the

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United States. 10 Therefore, they contributed nothing to the production of healthcare in Canada. In trying to understand and reverse thi s phenomenon, anadian economist and poli cymakers have identified a number of incentive at play. The most famili ar is the remunerati ve differenti al with the appeal of higher net income in certain specialti es in the US (due in part to their lower taxation rates).'o By identi fy ing the pertinent incenti ves, policymakers can dev ise new strategies to alter them. However, policymakers al o need to be care ful due to the unde irabl e con equences that may result when all incenti ves have not been taken into acco un t. In many cases, hidden incenti ves are overlooked and lead to unintended consequences. For exampl e, in the physician-patient relation hip, the phy ician is not onl y an agent hired to act in the be t interest of the patient but is also the sell er of health ervices. 7 In a fee-for-service compen ation method, the idea is to compensate the physician based on the services the patients receive. Phys ician who perform more services are thought to provide more healthcare and should be compensated accordingly. However, since the income of the phy ician is linked to how many services he or she provides, there is an incenti ve to promote more procedure than would otherwi se be nece ary. 11 These additi onal services are not onl y wasteful fo r the economy and lower effi ciency, but they may in fact do harm by leading to poorer outcomes in patient who receive superfluous procedures.7•11

HOW TO COMPARE APPLES AND ORANGES: VALUATION AND COST-BENEFIT ANALYS IS The focus of hea lthcare di scussion is frequentl y directed at curbing the ri sing costs, and this cost cri sis of hea lthcare dominates the headlines. 12• 13• 14 It sometimes becomes easy to forget that we value hea lthcare because we wa nt more of its output: health itself. The va lue of healthcare is not in the number of patient appointment or pill s prescribed, but in the number of li ves saved and the improvement in health outcome. By placing a va luation on health , the important outcomes such as quanti ty and qua lity of life can be mea ured and expressed. If two medi ca l intervention have equivalent cost, and intervention A can add 3 years to life expectancy and interventi on B onl y adds one yea r, it becomes quite clear whi ch is superior. In evaluating any project or program, it is important to compare the va lue of what was bought to its cost. Economi sts use this principle of cost-benefit analysi when evaluating healthcare programs.7 When applied on a larger sca le, it offers the potential for comparing different healthcare interventions and even comparing program in health and non-h ealth sectors. Noti ce that the interventions in the examples above could have been compl etely unrelated . Intervention A could be a cancer fi ghting drug and intervention B a surgical procedure for coronary heart di sease. By placing a valuation on both the inputs (the costs of production) and the outputs (the benefits of health improvement) , unrelated interventions can be compared. Through a comprehensive costbenefit evaluation, economic analysis can help policymakers make difficult deci sions such as which projects to all ocate more resources into, assessing whether a new intervention is superior to the old standard, and in choosing between comparable alternatives 7, l6 If applied across all healthcare sectors, policymakers can transfer funding from high-cost low-benefit programs with the reallocation of these resource into low-cost high-benefit programs. By minimizing costs and maximizing benefit, the overall effect has to potential to improve efficiency in the system and increase productivity.7· 15

CONCLUSIONS AND LIMITATIONS Economic principles and methods offer an approach to addressing healthcare problems. Many observers claim that economics is irrelevant to the study of health and some have argued that health

care is fundamenta lly so di ffe rent fro m other good that fina ncial incenti ves do not pl ay much of a role. Many will argue that when dea ling with life and death, hea lthcare consumers cannot be expected to maintain rati onal thinking 7 ·15 Empiri cal evidence suggests thi s is too extreme a posi ti on.? Price and financial incentives definitely do influence both the production and the consumption of hea lthcare. The more challenging questi on is to what ex tent it doe . The hea lthcare sector has a unique combinati on o f fea tures: the pro minent public sector, restri cti ons on competiti on, and lac k o f informati on. Combining this with the ex tensive uncertainty that ex ists both in the suppl y and demand side of hea lthcare compli cates economi c analyses. 7 With certain good , both suppli er and consumer have a good understanding of the product. For example, with orange j ui ce, upplier know how many oranges are needed to produce the juice and are confident of the quali ty of the juice, and consumers know how much sati sfaction they will rece ive when drinking a unit of the juice. With hea lthcare, both the phys icians and pati ents are often uncertain of the outcomes. Rheumatologists are often uncertain of how pati ent will respond to a parti cular anti-infl ammatory and pati ents themselves are un ure of the benefit to their length or quali ty of li fe . With di ffic ulties in measuring outcome and va luation, the accuracy of the analy is can often be ca ll ed into questi on. In the end, modeling can onl y be as good as the info rmati on input. Nevertheless, economi c principles and their methods can be a powerfu l and important tool when thinking about is ues in hea ltbcare. One impl y has to realize that li ke all too ls, economi c analysis in hea lthcare is imperfect and subj ect to limitations.

REFERENCES I. MacQueen K. Our health care delusion. Macleans. Jan 20 II . 2. Canadian Institute for Health In fo rmation. Hea lth Care in Canada 2009: A Decade in Review. Ottawa, Ont. : C!HI , 2009. 3. Deloitte Centre for Health Solutions. 20 II Survey of Health Care Consumers in Canada: Key Find ings, Strategic Implications. Deloitte Development LLC. 20 II . 4. Patel MS, Lypson ML, Davis MM . Medical student perception of education in health care ystem . Acad Med. 2009 Sep;84(9): 1301-6. 5. Bein B. Medical Students Not Satisfied With Trai ning in Health ystems, Medical Economics. AAF P ews Now. Nov 2009. <http -ljwww aafp org/ on Iine/en/home/pub licat ions/news/news-n ow/res ident-s tudent- foc us/ 200911 25med-econ-trng ht ml> 6. Gregory Mank.i w et. al., Principles of Microeconomics. el on College Indigenous. 4th Canadi an Edition, 2008. 7. Folland S, Goodman A, Miron . The Economics of Health and Health Care. Pearson. Fifth Edition, 2007 8. Canadian Industry tati ti cs. Gross Domestic Product (G OP) and GOP Growth : 200 1-20 10. Canadian Economy (NA IC 11 -91). tatistics Ca na d a . < http '// ww w ic gc ca / e ic / s it e/c is - s ic nsf/e ng / h 0001 3 htm l#vla2a> 9. Canadian Insti tute fo r Health In fo rmation. ational Health Expenditure Trends, 1975 to 20 I0. Ottawa, Ont.: C!HJ , 20 I0. I0. Phill ips R.L Jr, Petterson S, Fryer GE Jr, Rosser W. The Canadian contri bution to the US physician workforce. CMAJ. 2007 Apr I0; 176(8): 1083-7. II . Broomberg J, Price MR. The impact of the fee-for-service reimbursement system on the utilisation of hea lth services. Part I. A rev iew of the determinants of doctors' practi ce patterns. S Afr Med J. 1990 Aug 4;78(3): 130-2. 12. 12. Sibonney C. oaring costs force Canada to rea ess health model. Reuters. May 20 I0. <http'Uwww reuters com/article/?0 IO/OS/31/ushealth-idUSTRE64U3X020 I00531> 13. 13. Mason G. This health-care crisis wi ll require more than aving around the edges. Globe and Mail. Jan 20 I0. <hnp '//www theg!obeandmail com/ news/opinion s/thi s-health-care-cri sis-wi 11-requi re-more-than-say ingsaround-the-edges/article 1446642/> 14. Ca nadi an Hea lth ca re in Cri is. CBSnews. Feb 2009. <h.ttp,;lL www cbsnews com/stories/2005/03/20/health/main68180 I shtm l> I5. Cutler D. Your money or your health . Oxford Uni ver ity Press. New York 2004 . 16. Robinson R. Cost-benefit analysis. BMJ. 1993 Oct 9;307(6909):924-6.

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