5th International Hydrocephalus Workshop by ARTION Conferences & Events

ABSTRACT BOOK FINAL PROGRAMME

5th International Hydrocephalus Workshop 20 – 23 May 2010 Creta Maris Convention & Golf Resort Crete – Greece www.hydrocephaluscrete2010.gr Jointly organised by the Hellenic Neurosurgical Society and the Department of Neurosurgery, Medical College of Virginia, Commonwealth University, USA In affiliation with the International Society for Hydrocephalus and CSF Disorders

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

President’s Message Dear Friends and Colleagues, Welcome to the 5th International Hydrocephalus Workshop on the beautiful and historic island of Crete. This 5th Workshop is dedicated to Dr. Anthony Marmarou who conceived of the process of having these meetings and did most of the planning prior to his untimely death. Tony meant a great deal to all of us and was critical in the development of both the science surrounding hydrocephalus, as well as the clinical management of Normal Pressure Hydrocephalus. As part of the meeting, there will be a session emphasizing the vital role that Tony played in the advancement of the understanding of hydrocephalus. Dr. Kouzelis, the President of the Hellenic Neurosurgical Society and Vice President of the Workshop, and I would like to welcome you to the Creta Maris Convention & Golf Resort, an ideal location for scientific interchange in an idyllic setting. We look forward to the active participation of all the attendees and resuming long-standing friendships. This year specific attention will be paid to the completion of a project begun at the Hydrocephalus meetings in Goteborg, Hannover and Rhodes to produce a consensus on a contemporary definition and classification of hydrocephalus. I look forward to the input of all of you in this important task and the active participation of all in the scientific sessions. Your ideas matter and we are looking forward to hearing what you have to say.

Best Regards,

Harold L. Rekate MD President of the 5th International Hydrocephalus Workshop

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Vice President’s Address Dear Colleagues and Friends, The Hellenic Neurosurgical Society is particularly pleased to be involved once again this year in organising the 5th International Hydrocephalus Workshop on the charming Aegean island of Crete. Drawing on the fact that the previous workshops were a complete success, we believe that this event will be a major turning point, and will make a significant contribution to the effort to ensure further understanding of timely diagnosis and treatment of hydrocephalus. The wide number of topics covered, the outstanding credentials of our guest speakers and the option of all workshop participants to become actively involved in its proceedings, guarantee that this objective will be achieved. We would like to hope that we will be able to follow Ariadne’s lost thread through the ruins of the ancient Minoan labyrinth on the mythical island of Crete, and find the much sought after solution to the ancient Hippocratic riddle of hydrocephalus. We are also very pleased that the 5th International Hydrocephalus Workshop will follow the 24th Annual Hellenic Congress of Neurosurgery with international participation and the 4th Annual Neurosurgery Nurses Meeting (19 - 20 May 2010). Simultaneous interpretation of the proceedings into English and the presentation of papers in both Greek and English will also allow you to participate in our Society’s Congress which you are most welcome to attend. The members of the Organizing Committee are making every effort to ensure that you have an unforgettable stay and hope that the island’s boundless natural beauty, Crete’s famed diet and entertainment, as well as the warm local welcome will make sure that the 5th International Hydrocephalus Workshop will become one of your sweetest memories. Best Regards,

Konstantinos Kouzelis MD Vice President of the 5th International Hydrocephalus Workshop

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Organising & Scientiﬁc Committee President

Harold L. Rekate

Vice President

Konstantinos Kouzelis

Gen. Secretary

Panagiotis Selviaridis

Members

Alexandros Andreou Georgios Arhontakis Dimitris Arvanitakis Emmanouil Chatzidakis Nikolaos Foroglou Konstantinos Fountas Evangelos Markakis Ioannis Mpaltas Georgios Orfanidis Konstantinos Paterakis Ioannis Patsalas Sryros Sgouros Antonis Vakis Vasilios Varsos

Invited Speakers Gunes Aygok MD PhD Shlomi Constantini MD MSc Marek Czosnyka PhD Harold F Young MD Neil Graﬀ-Radford MD Andre Grotenhuis MD Masatsune Ishikawa MD PhD John Kestle MD Petra Klinge MD PhD Mark Luciano MD PhD Michael Pollay MD PhD Norman Relkin MD PhD Spyros Sgouros MD FRCS(SN) Carsten Wikkelso MD PhD Michael Williams MD 8

Crete

hosts the 5th International Hydrocephalus Workshop Crete is the southest point of Europe in the crossroad of three continents and five seas. It is the meeting point of different populations, by ancient and disparate cultures of centuries. It is the largest island in Greece and the fifth largest in the Mediterranean Sea, with a unique blend of elements from the creative assimilation of various cultural forms in a natural frame of astonishing beauty. Crete is full of beautiful beaches, traditional villages, each with its own history and huge variety of gorgeous landscapes. Crete’s history dates back to 5,000 years ago. Crete was the centre of the oldest Greek civilization, the Minoan civilization (circa 2600 –1454 BC), which was destroyed by natural disaster. As a Greek city state, Crete successively became part of the Roman Empire, the Byzantine Empire, the Venetian Republic, the Ottoman Empire and the modern state of Greece. The unique combination of tradition with its modern life and the amazing scenery makes Crete one of the world’s favourite travel destinations.

Venue & Accommodation The 5th International Hydrocephalus Workshop will take place at:

Creta Maris Convention & Golf Resort

Limin - Hersonissos, 70014, Crete, Greece T: +30 28970 27000 F: +30 28970 22130 W: www.maris.gr

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Credits of Continuous Medical Education In compliance with UEMS/EACCME, the attendance to the 5th International Hydrocephalus Workshop and the 24th Annual Hellenic Congress of Neurosurgery will be accredited with Credits of Continuous Medical Education (CME-CPD).

Language The official languages of the Workshop are English and Greek.

Thematic Sessions Progress and Controversies in Treatment of Adult and Pediatric Hydrocephalus Advances in Management of Hydrocephalus Pathophysiology Experimental Studies Less Invasive Studies in INPH Identifying Shunt Responders Outcome Scales Clinical Experience in ETV Mathematical Modeling Pulsatile Wave from Utility CSF Outﬂow Resistance Utility Shunt Technology CSF Biomarkers MRI in Hydrocephalus Adjustable vs Fixed Valves Anti-Siphon Devices ICP in Hydrocephalus Tap vs ELD Utility Inﬂuence of Co-Morbidity Alzheimer and NPH Parkinson’s and NPH Guidelines Clinical Trials CSF and Interstitial Fluid

Workshop Secretariat The Workshop Secretariat will operate throughout all sessions of the 5th International Hydrocephalus Workshop during the following hours Thursday May 20, 2010 Friday May 21, 2010 Saturday May 22, 2010 Sunday May 23, 2010

8:00 – 18:30 7:45 – 18:15 8:00 – 18:00 9:00 – 13:30 ARTION Conferences & Events Att: 5th International Hydrocephalus Workshop 9th km Thessaloniki - Thermi, Thomas Building P.O. Box 60705, GR 57001 Thessaloniki Tel.: Fax: E-mail: Website:

+30 2310 250928 (direct line), +30 2310 272275 +30 2310 272276, +30 2310 277964 hydrocephalus10@artion.com.gr www.hydrocephaluscrete2010.gr

Workshop Coordinator Despina Amarantidou

Secretariat – Hotel Accommodation Matina Katsarou, Niki Chatziilia

Sponsorship

Marianna Georgitseli

Publications & Website

Maria Kantziari, Ioanna Kazantzidou 11

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Exhibition area During the 5th International Hydrocephalus Workshop an exhibition of technical equipment and pharmaceutical products takes place in a spacious area adjacent to the Workshop room.

:%53 -AINÜWORKSHOPÜHALL

#ONTROL

3%#2%4!2)!4

%.42!.#%

6%2!.$!

4%#(.)#!, 3%#2%4!2)!4

:%53Ú4%22!#%

Exhibitors Company

Stand

AESCULAP AG

4&5

AKAHAI

AMI S.A.

ΑMVIS HELLAS S.A.

CORMED INTERNATIONAL

8&9

DEPUY – CODMAN

10 -11

GENESIS PHARMA S.A.

G. SURGIWEAR LIMITED INDIA

INTEGRA NEUROSCIENCES LIMITED

16 & 18

KK MEDICAL SPECIALIST S.A.

LIKVOR

6&7

MART HELLAS S.A.

28 & 29

MEDIFIELD Ltd.

MEDTRONIC HELLAS S.A.

20 & 22

ORTHOMEDICAL

PENY SIDERIS PANTAZIS

PHARMEX S.A.

RΕVIVAL SA THE PHYSICAL REHABILITATION CENTER OF THESSALONIKI

UCB S.A.

Z SPINE HELLAS Ltd.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Thankings The Organising Committee is thanking the sponsors for their ďŹ nancial contribution and their support to the 5th International Hydrocephalus Workshop.

Golden Sponsors

Silver Sponsors

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Programme Overview Level 1, Zeus Hall

Thursday May 20, 2010 8:00-18:30

Registrations

19:30

Official Opening Ceremony – Welcome Reception 5th International Hydrocephalus Workshop & 24th Annual Hellenic Congress of Neurosurgery

Friday May 21, 2010 7:45-8:00

Session I

Welcome and Announcements Harold L. Rekate, President of the 5th International Hydrocephalus Workshop Konstantinos Kouzelis, Vice President of the 5th International Hydrocephalus Workshop and President of the Hellenic Neurosurgical Society

Deﬁnition and classiﬁcation

Moderators Carsten Wikkelso, President ISHCSF Petra Klinge, President-Elect ISHCSF

8:00-8:30

The definition and classification of hydrocephalus: A consensus statement from the Hydrocephalus Classification Study Group Harold L. Rekate MD

8:30-9:00

Treatment of hydrocephalus based on the new classiﬁcation Spyros Sgouros MD FRCS(SN)

9:00-9:30

Clinical research in hydrocephalus Where are we now and where are we going? John Kestle MD

9:30-10:00

International study of infant hydrocephalus Shunts vs. ETV Shlomi Constantini MD MSc

10:00-10:30

Coﬀee with exhibitors

Session II

Pediatric hydrocephalus

Moderators Shlomi Constantini, Thomas Brinker

Programme Overview

10:30-12:00

Oral presentations

12:00-13:00

Poster discussions

13:00-14:00

Lunch and poster viewing

Session III

Special session: The importance of Dr. Anthony Marmarou

Moderators Harold L. Rekate, President of the 5th International Hydrocephalus Workshop Konstantinos Kouzelis, Vice-President of the 5th International Hydrocephalus Workshop and President of the Hellenic Neurosurgical Society 14:00-14:30

Modeling of CSF dynamics and cerebral blood ďŹ&#x201A;ow Marek Czosnyka PhD

14:30-15:00

The practice guidelines for the diagnosis and management of NPH History and perspectives Petra Klinge MD PhD

15:00-15:15

The NPH program at Medical College of Virginia: Patient Selection Gunes Aygok MD PhD

15:15-15:30

The NPH program at Medical College of Virginia: Surgical management Harold F. Young MD

15:30-16:00

Break with exhibitors

Session IV

Engineering aspects

Moderators Michael Pollay, Panagiotis Selviaridis

16:00-17:10

Oral presentations

17:10-18:10

Poster presentations

20:00

Cretan night (optional â&#x20AC;&#x201C; please consult the Workshop Secretariat)

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Saturday May 22, 2010 Session V

The basic science of hydrocephalus

Moderators John Kestle, Vasilios Varsos

08:00 – 10:00

Oral presentations

10:00-10:30

Break with exhibitors

Session VI

Physiology and neuroimaging

Moderators Jogi Pattisapu, Spyros Sgouros

10:30-11:00

Overview of the dual CSF outﬂow system Michael Pollay MD PhD

11:00-11:30

Cranial pulsatility: Physiologically important or just a passing wave Mark Luciano MD PhD

11:30-12:00

Disproportionately enlarged subarachnoid-space hydrocephalus Matsasune Ishikawa MD PhD

12:00-12:30

Neuro-imaging of hydrocephalus What’s missing from the picture? Norman Relkin MD PhD

12:30-13:30

Lunch and poster viewing

Level 0, Minos Hall Session VII

Clinical studies

13:30-14:00

Ethical considerations in hydrocephalus research in children and adults Michael Williams MD

14:00-14:30

Alzheimer disease, systemic hypertension and congenital factors What are their roles in normal pressure hydrocephalus? Neil Graff-Radford MD

14:30-15:00

Adjustable valves in the treatment of INPH Carsten Wikkelso MD PhD

Moderators Michael Kiefer, Alexander Andreou

Programme Overview

15:00-15:30

Lessons learned and questions raised during 20 years of ETV Andre Grotenhuis MD

15:30-16:00

Break with exhibitors

Session VIII

Neuroendoscopy

Moderators Martin Schuhmann, George Stratzalis

16:00-18:00

Oral presentations

20:30

Gala dinner

Sunday May 23, 2010 Session IX

NPH and diagnosis

Moderators Michael Pollay, Marek Czosnyka

09:00 â&#x20AC;&#x201C; 10:30

Oral presentations

10:30 â&#x20AC;&#x201C; 10:50

Break with exhibitors

Session X

NPH and shunts

Moderators Mark Luciano, Konstantinos Polyzoidis

10:50-13:00

Oral presentations

13:00-13:30

Summary of the accomplishments of the meeting Harold L. Rekate, Kostantinos Kouzelis, Michael Pollay

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Final Programme Level 1, Zeus Hall

Thursday May 20, 2010 8:00-18:30

Registrations

19:30

Official Opening Ceremony – Welcome Reception 5th International Hydrocephalus Workshop & 24th Annual Hellenic Congress of Neurosurgery

Friday May 21, 2010 7:45-8:00

Session I

Deﬁnition and classiﬁcation

Moderators Carsten Wikkelso, President ISHCSF Petra Klinge, President-Elect ISHCSF

8:00-8:30

The definition and classification of hydrocephalus: A consensus statement from the Hydrocephalus Classification Study Group Harold L. Rekate MD

8:30-9:00

Treatment of hydrocephalus based on the new classiﬁcation Spyros Sgouros MD FRCS(SN)

9:00-9:30

Clinical research in hydrocephalus Where are we now and where are we going? John Kestle MD

9:30-10:00

International study of infant hydrocephalus Shunts vs. ETV Shlomi Constantini MD MSc

10:00-10:30

Coﬀee with exhibitors

Session II

Pediatric hydrocephalus

Moderators Shlomi Constantini, Thomas Brinker

Final Programme

10:30-12:00

Oral presentations

O01. QUALITY AND SAFETY OF HOME ICP MONITORING COMPARED TO IN-HOSPITAL MONITORING Andresen M., Juhler M., Munch T. Clinic of Neurosurgery, Copenhagen University Hospital, Denmark O02. PATHOPHYSIOLOGY OF BRAIN STEM LESIONS DUE TO OVERDRAINAGE Antes S., Eymann R., Schmitt M., Kiefer M. Saarland University, Medical School, Department of Neurosurgery, Homburg-Saar, Germany O03. INAPPROPRIATELY LOW-PRESSURE (NEGATIVE-PRESSURE) HYDROCEPHALUS: EXPERIENCE WITH 20 PATIENTS Hamilton Μ., MDCM, FRCSC Department of Clinical Neurosciences, Division of Neurosurgery, University of Calgary, Canada O04. ADULTS TREATED FOR INFANTILE HYDROCEPHALUS – A VERY LONG TERM FOLLOW-UP STUDY Persson E.K. MD PhD, Lindquist B. PhD, Fernell E. MD PhD, Uvebrant P. MD PhD Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Sweden O05. MEDICATION OVERUSE AS A CAUSE OF CHRONIC HEADACHE IN SHUNTED HYDROCEPHALUS PATIENTS Juhler M., Willer L., Jensen R.H. Department of Neurosurgery, Rigshospitalet, Denmark The Headache Research Centre, Glostrup Hospital, Denmark O06. TREATMENT OF PREMATURE CHILDREN WITH POSTHEMORRHAGIC HYDROCEPHALUS BY TEMPORARY METHODS OF ICP NORMALISATION Zinenko D., Vladimirov M., Haﬁzov F. Moscow Pediatric and Children Surgery Research Institute, Russia O07. SHUNT SURGERY CAN BE AVOIDED IN MOST PATIENTS WITH BENIGN INTRACRANIAL CYSTS Högfeldt M.1, Tisell M.1, Hellström P.2, Edsbagge M.2, Wikkelsö C.2 (1) Department of Neurosurgery, Sahlgrenska University Hospital Gothenburg, Sweden (2) Department of Neurology, Sahlgrenska University Hospital Gothenburg, Sweden O08. ASYMPTOMATIC TREATMENT FAILURE IN PEDIATRIC HYDROCEPHALUS - FEATURES OF AN UNDER-DIAGNOSED (?) ENTITY Schuhmann M. U.1, Speil A.2, Haas-Lude K.2, Alber M.2, Bevot A.2 (1) Section of Pediatric Neurosurgery, Department of Neurosurgery, Eberhard Karls University Hospital, Tuebingen, Germany (2) Department of Pediatric Neurology, Eberhard Karls University Children‘s Hospital, Tuebingen, Germany O09. THE MANAGEMENT AND THE OUTCOME OF INTRAVENTRICULAR HEMORRHAGE IN BABIES WITH LOW BIRTH WEIGHT Inagaki T.1, Kawamoto K.2, Kinoshita Y.3 (1) Pediatric Neurosurgery, Kansai Medical University, Japan (2) Neurosurgery, Kansai Medical University, Japan (3) Pediatrics, Kansai Medical University, Japan 12:00-13:00

Poster discussions

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Associated disorders P01. POSTCRANIECTOMY HYDROCEPHALUS Venetikidis A., Paleologos T.S., Markellos A., Papanikolaou P.G., Stamatiou S., Voidonikolas L., Georgoulis G., Damilakis K., Kiriakou T. Department of Neurosurgery, General Hospital Nikaia-Piraeus, Greece P02. POST-TRAUMATIC HYDROCEPHALUS IN SEVERE HEAD INJURY - SERIES OF 9 CASES Syrmos N.1, Iliadis Ch.1, Barkatsa V.1, Valadakis V.1, Grigoriou K.1, Gavridakis G.2, Arvanitakis D.1 (1) Department of Neurosurgery, Venizeleio General Hospital, Heraklion, Crete, Greece (2) CT Scan Department, Venizeleio General Hospital, Heraklion, Crete, Greece P03. LHERMITTE-DUCLOS DISEASE PRESENTING WITH HYDROCEPHALUS: CASE REPORT AND LITERATURE REVIEW Choong Hyun Kim MD PhD, Jin Hwan Cheong MD PhD, Jae Min Kim MD PhD Department of Neurosurgery, Hanyang University, Guri, Korea Discussion

Complications P04. RARE ABDOMINAL COMPLICATIONS OF VENTRICULO-PERITONEAL (VP) SHUNTS Paidakakos N., Rokas E., Theodoropoulos S., Dimogerontas G., Rovlias A., Makrigiannakis G., Papadopoulos M., Konstantinidis E. Department of Neurosurgery, Asclepeion General Hospital of Voula, Athens, Greece P05. INFECTIONS AFTER CEREBROSPINAL FLUID SHUNT IN ELDERLY PATIENTS Syrmos N.1, Iliadis Ch.1 , Barkatsa V.1, Valadakis V.1, Grigoriou K.1, Gavridakis G.2, Arvanitakis D.1 (1) Department of Neurosurgery, Venizeleio General Hospital, Heraklion, Crete, Greece (2) CT Scan Department, Venizeleio General Hospital, Heraklion, Crete, Greece P06. VENTRICULOATRIAL SHUNTS: PREDICTORS OF FAILURES Batra S., Solomon D., Moghekar A., Blitz A., Rigamonti D. The Departments of Neurology and Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, USA P07. ENDOSCOPIC BRAIN-WASHING ON TREATMENT OF VENTRICULAR INFECTION Qing Xiao, Guo-qiang Chen, Jia-ping Zheng, Jin-ting Wu, Hui Liang, Huan-cong Zuo Department of Neurosurgery, Yuquan Hospital, Tsinghua University, Beijing, China Discussion

Associated disorders P08. A 40-YEAR SERIES WITH 1070 SYRINX- AND CHIARI-PATIENTS Aschoﬀ A.1, Akbar M.2, Wiedenhöfer B.2, Muhcu S.1, Orakcioglu B.1, Geletneky C.1 (1) Department of Neurosurgery, University of Heidelberg, Germany (2) Department of Orthopaedics, University of Heidelberg, Germany

Final Programme

P09. EXPRESSION ANALYSIS OF HIGH MOBILITY GROUP BOX-1 PROTEIN (HMGB-1) IN THE CEREBRAL CORTEX, HYPPOCAMPUS, CEREBELLUM OF THE CONGENITAL HYDROCEPHALUS RAT (H-TX) Mitsuya Watanabe MD, Masakazu Miyajima MD, Madoka Nakajima MD, Hajime Arai MD, Ikuko Ogino, Sinji Nakamura, Miyuki Kunichika Department of Neurosurgery, Juntendo University, Bunkyoku, Tokyo, Japan P10. ATYPICAL MENINGIOMA IN THE POSTERIOR FOSSA ASSOCIATED WITH COLPOCEPHALY AND CORPUS CALLOUS AGENESIS Choong Hyun Kim MD PhD, Jin Hwan Cheong MD PhD, Jae Min Kim MD PhD Department of Neurosurgery, Hanyang University, Guri, Korea

Potpourri P11. EFFECT OF ANTIBIOTIC IMPREGNATED SHUNTS ON INFECTION RATE IN ADULT HYDROCEPHALUS: A SINGLE INSTITUTION’S EXPERIENCE Harrison Farber S., Parker S.L., Adogwa O., McGirt M.J., Solomon D., Rigamonti D. The Departments of Neurology and Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, USA P12. THE OBSTRUCTIVE NATURE OF PEDIATRIC HYDROCEPHALUS RESULTS OF A HIGH-RESOLUTION MRI STUDY Schuhmann M.U.1, Filip Z.1, Ries B.G.2, Tatagiba M.S.1, Nägele T.1 (1) Section of Pediatric Neurosurgery, Department of Neurosurgery, Eberhard Karls University Hospital, Tuebingen, Germany (2) Department of Neuroradiology, Eberhard Karls University Hospital, Tuebingen, Germany P13. SHUNT RELATED OCCLUSIVE EXTERNAL HYDROCEPHALUS Zinenko D. Moscow Pediatric and Children Surgery Research Institute, Russia Discussion 13:00-14:00

Lunch and poster viewing

Session III

Special session: The importance of Dr. Anthony Marmarou

Moderators Harold L. Rekate, President of the 5th International Hydrocephalus Workshop Konstantinos Kouzelis, Vice President of the 5th International Hydrocephalus Workshop and President of the Hellenic Neurosurgical Society 14:00-14:30

Modeling of CSF dynamics and cerebral blood ﬂow Marek Czosnyka PhD

14:30-15:00

The practice guidelines for the diagnosis and management of NPH History and perspectives Petra Klinge MD PhD

15:00-15:15

The NPH program at Medical College of Virginia: Patient Selection Gunes Aygok MD PhD 23

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 15:15-15:30

The NPH program at Medical College of Virginia: Surgical management Harold F. Young MD

15:30-16:00

Break with exhibitors

Session IV

16:00-17:10

Engineering aspects

Moderators Michael Pollay, Panagiotis Selviaridis Oral presentations

O10. SLOW VASOGENIC FLUCTUATIONS OF INTRACRANIAL PRESSURE AND CEREBRAL NEAR INFRARED SPECTROSCOPY – AN OBSERVATIONAL STUDY Czosnyka Z.1, Weerakkody R. A.1, Czosnyka M.1, Balédent O.2, Souraya Stoquart El-sankari2, Pickard J.1 (1) Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK (2) Department of Medical Physics and Imaging, University of Amiens Hospital, Amiens, France (3) Department of Neurology, Cliniques Universitaires Saint-Luc, Brussels, Belgium O11. WHO NEEDS A SHUNT? CSF DYNAMICS PERSPECTIVE Czosnyka M.1, Schuhmann M.2, Werrakody R.1, Keong N.2, Santarius T.1, Schmidt EA.4, Balédent O.1, Pickard JD.1, Czosnyka Z.1 (1) Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK (2) Department of Neurosurgery, University of Tuebingen, Germany (3) Department of Medical Physics and Imaging, University of Amiens Hospital, France (4) Neurosurgery, Hopital Pourpan, Toulouse, France O12. SIMULATION OF SHUNT VALVES IN A HYDROCEPHALUS MODEL Krause I.1, Walter M.1, Kiefer M.2, Leonhardt S.1 (1) Chair for Medical Information Technology, Helmholtz-Institute, RWTH Aachen, Germany (2) Neurosurgery, Saarland University, Medical School, Homburg-Saar, Germany O13. REALISTIC PHANTOM OF CRANIO-SPINAL HYDRODYNAMICS Bouzerar R.1, Czosnyka M.2, Czosnyka Z.2, Balédent O.1 (1) Department of Medical Physics and Imaging, University of Amiens Hospital, Amiens, France (2) Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK O14. CSF DYNAMIC PROFILE OF POTENTIAL SHUNT CANDIDATES IN COMPARISON WITH HEALTHY ELDERLY Frankel J. MSc1, Eklund A. PhD1,2, Malm J. MD PhD3 (1) Department of Biomedical Engineering, Umeå University Hospital, Sweden (2) Department of Radiation Sciences, Umeå University, Sweden (3) Department of Clinical Neuroscience, Umeå University, Sweden O15. ESTIMATION OF OUTFLOW RESISTANCE – MODEL DEPENDENCY Eklund A. PhD1,2, Andersson K. MSc2, Malm J. MD PhD3 (1) Department of Biomedical Engineering, Umeå University Hospital, Sweden (2) Department of Radiation Sciences, Umeå University, Sweden (3) Department of Clinical Neuroscience, Umeå University, Sweden

Final Programme

Poster presentations

Engineering aspects 1 P14. ICMPLUS SOFTWARE USED FOR ASSESSMENT OF CSF DYNAMICS Czosnyka Z., Czosnyka M., Pickard J.D., Smielewski P. Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK P15. PROGRAMMABLE SHUNT ASSISTANT TESTED IN CAMBRIDGE SHUNT EVALUATION LABORATORY Czosnyka M., Czosnyka Z. Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK P16. FAST FOURIER TRANSFORMATION (FFT) FOR ICP SLOW WAVES DETECTION Kiefer M.1, Schmitt M.1, Antes S.1, Krause I.2, Eymann R.1 (1) Department of Neurosurgery, Medical School, Saarland University, Homburg-Saar, Germany (2) Philips Chair for Medical Information Technology, Helmholtz-Institut, Aachen, Germany P17. EXAMINATION OF DEPOSITS IN CSF SHUNT VALVES USING SCANNING ELECTRON MICROSCOPY Charalambides C., Sgouros S. Department of Neurosurgery, “Attikon” University Hospital, University of Athens, Greece Discussion

Engineering aspects 2 P18. ICP ANALYSIS IN NPH: COMPARISON OF TIME-DOMAIN DERIVED VERSUS FREQUENCYDOMAIN DERIVED PULSE WAVE AMPLITUDE AND RELATED PARAMETERS Schuhmann M.U.1, Buddhakoralage S.1, Speil A.1, Helm J.2, Jaeger M.2, Eide P.3 (1) Section of Pediatric Neurosurgery, Department of Neurosurgery, Eberhard Karls University Hospital, Tuebingen, Germany (2) Department of Neurosurgery, University of Leipzig, Leipzig, Germany (3) Department of Neurosurgery, Rikshospitalet, Oslo University Hospital, Oslo, Norway P19. AN INNOVATIVE PERMANENTLY IMPLANTED WIRELESS INTRACRANIAL PRESSURE MONITOR USING MEMS TECHNOLOGY AND MICROWAVE TELEMETRY FOR THE DIAGNOSIS OF HYDROCEPHALUS Kralick F.A.1, Kawoos U.2, Warty R.3, Toﬁghi M.R.4, Rosen A.2 (1) Department of Neurosurgery, Hahnemann University Hospital, Philadelphia, USA (2) Department of Biomedical Engineering, Drexel University, Philadelphia, USA (3) Department of Electrical Engineering, Philadelphia, USA (4) Penn State University, the Capital College, Middletown, USA

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 P20. MICROSTRUCTURAL ALTERATIONS OF SILICONE CATHETERS IN AN ANIMAL EXPERIMENT: HISTOPATHOLOGY AND SEM-FINDINGS Eymann R.1, Kim Y.J.2, Bohle R.M.2, Kiefer M.1 (1) Department of Neurosurgery, Medical School, Saarland University, Homburg-Saar, Germany (2) Department of Pathology, Medical School, Saarland University, Homburg-Saar, Germany Discussion

Selecting the right shunt P21. WHAT IS THE APPROPRIATE SHUNT SYSTEM FOR NORMAL PRESSURE HYDROCEPHALUS? Chrissicopoulos C.¹, Mourgela S.¹, Kirgiannis K.¹, Petritsis K.¹, Ampertos N.¹, Sakellaropoulos A.², Spanos A.¹ (¹) “Agios Savvas” Anticancer Institute, Department of Neurosurgery, Athens, Greece (2) “Neon Athineon” Hospital, Pulmonary and Critical Care Medicine, Athens, Greece P22. SURGICAL MANAGEMENT OF ADULT CHRONIC HYDROCEPHALUS BY USING VENTRICULO-PERITONEAL SHUNTS WITH ADJUSTABLE VALVES Paidakakos N., Rokas E., Theodoropoulos S., Dimogerontas G., Makrigiannakis G., Rovlias A., Papadopoulos M., Konstantinidis E. Department of Neurosurgery, Asclepeion General Hospital of Voula, Athens, Greece P23. ADJUSTABLE GRAVITATIONAL VALVES – TECHNICAL OVERKILL OR NECESSITY? Aschoﬀ A.1, Kiefer M.2, Kehler U.3, Jung C.1, Dictus C.1 (1) Department of Neurosurgery, University of Heidelberg, Germany (2) Department of Neurosurgery University of Homburg/S, Germany (3) Department of Neurosurgery, Asklepios Klinik Hamburg-Altona, Germany Discussion

Neuroendoscopy P24. ADULT ENDOSCOPIC THIRD VENTRICULOSTOMY IN OBSTRUCTIVE HYDROCEPHALUS Woodworth G.F., See A., Batra S., Jallo G.I., Solomon D., Rigamonti D. Departments of Neurology and Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, USA P25. EFFICACY AND SAFETY OF THE 2MICRON CONTINUOUS WAVE LASER IN NEURO-ENDOSCOPIC PROCEDURES Schuhmann M.U., Nagel C., Ebner F.E., Tatagiba M.S. Section of Pediatric Neurosurgery, Department of Neurosurgery, Eberhard Karls University Hospital, Tuebingen, Germany P26. BENIGN CEREBRAL AQUEDUCT STENOSIS IN AN ADULT Chrissicopoulos C.¹, Mourgela S.¹, Ampertos N.¹, Sakellaropoulos A.², Kirgiannis K.¹, Petritsis K.¹, Spanos A.¹ (1) “Agios Savvas” Anticancer Institute, Department of Neurosurgery, Athens, Greece (2) “Neon Athineon” Hospital, Pulmonary and Critical Care Medicine, Athens, Greece Discussion 20:00 26

Cretan night (optional – please consult the Workshop Secretariat)

Final Programme

Saturday May 22, 2010 Session V

08:00 – 10:00

The basic science of hydrocephalus

Moderators John Kestle, Vasilios Varsos Oral presentations

Ο17. CHANGES OF FRACTIONAL ANISOTROPY (FA) AND APPARENT DIFFUSION COEFFICIENT (ADC) IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Mase M.1, Demura K.1, Osawa T.1, HattoriI M.2, KasaiI H.3, Miyati T.4, Yamada K.1 (1) Department of Neurosurgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan (2) Department of Neurology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan (3) Department of Radiology, Nagoya City University Hospital, Nagoya, Japan (4) Faculty of Health Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan O18. MR-ELASTOGRAPHY IN NORMAL PRESSURE HYDROCEPHALUS PRE- AND POSTSHUNT – EVALUATION OF A NEW IN-VIVO METHOD AND IMPLICATIONS FOR PATHOGENESIS Sprung C.1, Freimann F.B.1, Streitberger K.J.2, Wiener E.3, Sack I.2 (1) Department of Neurosurgery, Charité - University Berlin, Campus Rudolf Virchow, Berlin, Germany (2) Department of Radiology, Charité - University Medicine Berlin, Campus Charité Mitte, Berlin, Germany (3) Department of Neuroradiology, Charité - University Medicine Berlin, Campus Charité Mitte, Berlin, Germany O19. NEW EPENDYMAL CELLS ARE BORN POSTNATALLY AND SUPPORT VENTRICULOMEGALY IN HYDROCEPHALIC MICE Bátiz L.F.1, Jiménez A.J.2, Toledo C.D.1, Guerra M.1, Vio K.1, Rodríguez-Pérez L.M.2, Páez P.2, Pérez-Fígares J.M.2, Rodríguez E.M.1 (1) Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile (2) Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain O20. GENE EXPRESSION PROFILING OF CHOROID PLEXUS IN ALZHEIMER’S DISEASE REVEAL IMPORTANT IMPLICATIONS FOR CSF DYNAMICS Stopa E.G.1, Nikonova E.V.2, Tanis K.Q.2, Podtelezhnikov A.A.2, Finney E.M.2, Stone D.J.2, Camargo L.M.2, Parker L.2, Verma A.2, Baird A.3, 4, Miller M.C.1, Donahue J.E.1, Gonzalez A.M.4, Eliceiri B.3, Silverberg G.D.1, Klinge P.M.1, Johanson C.E.1 (1) Departments of Neurosurgery and Pathology (Neuropathology Division), Rhode Island Hospital, The Warren Alpert Medical School, Brown University, Providence, RI, USA (2) Molecular Proﬁling & Research Informatics, Merck Sharp & Dohme, West Point, PA, USA (3) Department of Surgery, University of California San Diego Medical Center, San Diego, CA, USA (4) School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, UK 27

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O21. HYDROCEPHALUS AND AQUAPORINS. THE ROLE OF AQUAPORIN-1 Kalani MYS, Filippidis A.S., Rekate H.L. Division of Pediatric Neurosurgery, Barrow Neurological Institute, Phoenix, AZ O22. HYDROCEPHALUS AND AQUAPORINS. THE ROLE OF AQUAPORIN-4 Filippidis A.S., Kalani MYS, Rekate H.L. Division of Pediatric Neurosurgery, Barrow Neurological Institute, Phoenix, AZ O23. EXPERIMENTAL HYDROCEPHALUS INDUCES CHANGES IN CONSTITUTIVE AQUAPORIN-4 EXPRESSION AND CHANGES MORPHOLOGY OF AQUAPORIN-4 POSITIVE EPENDYMA Skjolding A.D.1, Rowland I.2, Soegaard L.V.2, Praetorius J.3, Penkowa M.4, Juhler M.1 (1) University Clinic of Neurosurgery, Rigshospitalet, Copenhagen, Denmark (2) Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital, Hvidovre, Denmark (3) The Water and Salt Research Center, Department of Anatomy, Aarhus University, Aarhus, Denmark (4) Section of Neuroprotection, Department of Neuroscience and Pharmacology, Faculty of Health Science, Copenhagen University, Copenhagen, Denmark O24. PRENATAL MOLECULAR DIAGNOSIS AND STEM CELL RESEARCH IN SEVERE TYPE OF L1CAM SYNDROME (X-LINKED HYDROCEPHALUS) Yamasaki M. MD PhD1,2, Nonaka M. MD PhD2, Shofuda T. MS1, Kanemura Y. MD PhD1,2 (1) Institute for Clinical Research, Osaka National Hospital, National Hospital Organization, Japan (2) Department of Neurosurgery, Osaka National Hospital, National Hospital Organization, Japan O25. EFFECT OF ACETAZOLAMIDE ON AQUAPORIN-1 EXPRESSION OF CULTURED CHOROID PLEXUS CELLS Pouya Ameli, Meenu Madan, Srinu Chigurupati, Amin Yu, Sic L. Chan, Jogi V. Pattisapu Hydrocephalus Research Laboratory, University of Central Florida College of Medicine O26. EXPERIENCE WITH FRONTO-TEMPORAL DEMENTIA IN PATIENTS SHUNTED FOR HYDROCEPHALUS Williams M.A., Wilson R.K., Smith C.A. Sandra and Malcolm Berman Brain & Spine Institute, Adult Hydrocephalus Center, Sinai Hospital of Baltimore, Baltimore, MD USA O27. DIFFUSION TENSOR IMAGING EXPOSES FURTHER LESIONS TO WHITE MATTER IN INPH Lenfeldt N. E.P. PhD MSc1,5, Larsson A. PhD2, Nyberg L. PhD2,3, Birgander R. MD PhD2, Eklund A. PhD2,4,5, Malm J. MD PhD1 (1) Department of Clinical Neuroscience, Umeå University, Sweden (2) Department of Radiation Sciences, Umeå University, Sweden (3) Department of Integrative Medical Biology, Umeå University, Sweden (4) Department of Biomedical Engineering and Informatics, Umeå University, Sweden (5) Centre for Biomedical Engineering and Physics, Umeå University, Sweden O28. QUANTITATIVE EVALUATION OF CSF CIRCULATION AT THE AQUEDUCT OF SYLVIUS IN 3T MR UNIT Kapsalaki E.1, Tsougos I.2, Theodorou K.2, Paterakis K.N.3, Fountas K.N.3 (1) Department of Diagnostic Radiology, University Hospital of Larisa, School of Medicine, University of Thessaly, Larisa, Greece (2) Department of Medical Physics, University Hospital of Larisa, School of Medicine, University of Thessaly, Larisa, Greece (3) Department of Neurosurgery, University Hospital of Larisa, School of Medicine, University of Thessaly, Larisa, Greece 10:00-10:30 28

Break with exhibitors

Final Programme

Session VI

Physiology and neuroimaging

Moderators Jogi Pattisapu, Spyros Sgouros

10:30-11:00

Overview of the dual CSF outďŹ&#x201A;ow system Michael Pollay MD PhD

11:00-11:30

Cranial pulsatility: Physiologically important or just a passing wave Mark Luciano MD PhD

11:30-12:00

Disproportionately enlarged subarachnoid-space hydrocephalus Matsasune Ishikawa MD PhD

12:00-12:30

Neuro-imaging of hydrocephalus Whatâ&#x20AC;&#x2122;s missing from the picture? Norman Relkin MD PhD

12:30-13:30

Lunch and poster viewing

Level 0, Minos Hall Session VII

Clinical studies

13:30-14:00

Ethical considerations in hydrocephalus research in children and adults Michael Williams MD

14:00-14:30

Alzheimer disease, systemic hypertension and congenital factors What are their roles in normal pressure hydrocephalus? Neil Graff-Radford MD

14:30-15:00

Adjustable valves in the treatment of INPH Carsten Wikkelso MD PhD

15:00-15:30

Lessons learned and questions raised during 20 years of ETV Andre Grotenhuis MD

15:30-16:00

Break with exhibitors

Session VIII

Moderators Michael Kiefer, Alexander Andreou

Neuroendoscopy

Moderators Martin Schuhmann, George Stratzalis

16:00-18:00

Oral presentations

20:30

Gala dinner

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O29. ENDOSCOPIC FOURTH VENTRICULOSTOMY ON TREATMENT OF FOURTH VENTRICLE OBSTRUCTIVE HYDROCEPHALUS Guo-qiang Chen, Qing Xiao, Jia-ping Zheng, Jin-ting Wu, Hui Liang, Huan-cong Zuo Department of Neurosurgery, Yuquan Hospital, Tsinghua University, Beijing, China O30. A PROSPECTIVE, RANDOMISED, CONTROLLED TRIAL TO EVALUATE THE EFFICACY AND SAFETY OF ENDOSCOPIC CHOROID PLEXUS COAGULATION WITH THIRD VENTRICULOSTOMY IN THE TREATMENT OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (ISRCTN29863839) Edwards R.J., Aquilina K., Bunnage M., Pople I.K. Department of Neurosurgery, Frenchay Hospital, Bristol, UK O31. NORMAL PRESSURE HYDROCEPHALUS (NPH): INDICATIONS FOR ENDOSCOPIC THIRD VENTRICULOSTOMY (ETV) Paidakakos N., Borgarello S., Naddeo M. Department of Neurosurgery, C.T.O. Hospital, Turin, Italy O32. COMPLICATIONS OF ENDOSCOPIC THIRD VENTRICULOSCOPY. A META-ANALYSIS Bouras T., Sgouros S. Department of Neurosurgery, “Attikon” University Hospital, University of Athens, Greece O33. THE ROLE OF ENDOSCOPIC THIRD VENTRICULOSTOMY IN THE TREATMENT OF SELECTED PATIENTS WITH NORMAL PRESSURE HYDROCEPHALUS Fountas K.N. MD PhD1, Kapsalaki E.Z. MD PhD2, Paterakis K.N. MD PhD1, Lee G.P. PhD3, Hadjigeorgiou G. MD PhD4 (1) Department of Neurosurgery, University Hospital of Larisa, University of Thessaly, School of Medicine, Larisa, Greece (2) Department of Diagnostic Radiology University Hospital of Larisa, University of Thessaly, School of Medicine, Larisa, Greece (3) Department of Neurology, Medical College of Georgia, Augusta, GA, USA (4) Department of Neurology, University Hospital of Larisa, University of Thessaly, School of Medicine, Larisa, Greece O34. THE ROLE OF ARTIFICIAL CEREBROSPINAL FLUID AS PERFUSATE IN NEUROENDOSCOPIC SURGERY-BASIC INVESTIGATIONMasakazu Miyajima, Misuya Watanabe, Madoka Nakajima, Ikuko Ogino, Hajime Arai Department of Neurosurgery, Juntendo University, Tokyo, Japan O35. A TWELVE-YEAR HOSPITAL OUTCOME ON PATIENTS WITH IDIOPATHIC HYDROCEPHALUS Stranjalis G.1,2, Kalamatianos T.1,2, Koutsarnakis C.1,2, Loufardaki M.1,2, Stavrinou L.1,2, Sakas D.E.1,2 (1) Department of Neurosurgery, University of Athens, Athens, Greece (2) HCNR “Professor Petros S. Kokkalis”, Athens, Greece O36. INTRACRANIAL PRESSURE ANALYSIS IN PATIENTS WITH CHIARI 1 MALFORMATION Radek Frič, Per Kristian Eide Department of Neurosurgery, Rikshospitalet, Oslo University Hospital, Norway O37. A 22-YEAR-SERIES OF 1042 PATIENTS WITH 1271 ADJUSTABLE VALVES Dictus C., Biedermann N., Piotrowicz A., Unterberg A., Vienenkoetter B., Schiebel P., Hertle D., Haux D., Jung C., Aschoﬀ A. Department of Neurosurgery, University of Heidelberg, Germany O38. THE IDIOPATHIC ADULT’S HYDROCEPHALUS. A HISTORICAL RESEARCH Missori P.1, Paolini S.2, Currà A.1 (1) Department of Neuroscience, Neurology and Neurosurgery, University of Rome “Sapienza”, Italy (2) University of Perugia, Neurosurgery, IRCCS “Neuromed” Pozzilli, Italy

Final Programme

O39. DYNAMICS OF CSF FLOW IN SLIT VENTRICLE SYNDROME Eymann R.1, Schmitt M.1, Antes S.1, Shamdeen M.G., Kiefer M. (1) Department of Neurosurgery, Medical School, Saarland University, Homburg-Saar, Germany (2) Department of Pediatrics, Medical School, Saarland University, Homburg-Saar, Germany

Sunday May 23, 2010 Session IX

09:00 – 10:30

NPH and diagnosis

Moderators Michael Pollay, Marek Czosnyka Oral presentations

O40. IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) IN A DEFINED POPULATION – LONG-TERM OUTCOME OF 172 SHUNTED PATIENTS Pyykkö O.T. BM1, Koivisto A. MD PhD3,4, Alafuzoﬀ I. MD PhD3,5, Vainikka S. MD, Tamminen J. MD2, Tillgren T. MD2, Savolainen S. MD PhD2, Fraunberg M. MD PhD2, Pirttilä T. MD PhD3,4, Jääskeläinen J.E. MD PhD1,2, Soininen H. MD PhD3,4, Rinne J. MD PhD2, Leinonen V. MD PhD2 (1) Department of Neurosurgery, Kuopio University Hospital, Kuopio, Finland and University of Eastern Finland (2) Department of Neurosurgery, Kuopio University Hospital, Kuopio, Finland (3) Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland (4) Department of Neurology, Kuopio University Hospital, Kuopio, Finland (5) Unit of Pathology, Department of Clinical Medicine, University of Eastern Finland, Kuopio, Finland O41. THE VALUE OF CEREBROSPINAL FLUID DYNAMICS (CSF) AND ITS CORRELATION WITH TAP TEST FOR THE PREOPERATIVE ASSESSMENT OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) PATIENTS Aygok G.A.1, Kayis C.2, Marmarou A.1, Young H.F.1 (1) Department of Neurosurgery, Medical College of Virginia, Commonwealth University, USA (2) Department of Electrical Engineering, Virginia Commonwealth University, Richmond, VA, USA O42. CORRELATION BETWEEN TAP TEST RESULTS AND CSF AQUEDUCTAL STROKE VOLUME IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS ElSankari S.1,2, Fichten A.3, Gondry-Jouet C.4, Csoznyka M.5, Legars D.3, Deramond H.4, Balédent O.2 (1) Neurology Department, Amiens University Hospital, Amiens, France (2) Imaging and Biophysics Unit, Amiens University Hospital, Amiens, France (3) Neurosurgery Department, Amiens University Hospital, Amiens, France (4) Radiology Department, Amiens University Hospital, Amiens, France (5) Academic Neurosurgical Unit, Department of Clinical Neurosciences, University of Cambridge, Addenbroke’s Hospital, Cambridge, UK O43. TAP TEST - TIME WINDOW AND CONSISTENCY Virhammar J.1, Cesarini K.G.2, Laurell K.1 (1) Department of Neuroscience, Uppsala University Hospital, Sweden (2) Department Neurology and Neurosurgery, Uppsala University Hospital, Sweden

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O44. NEUROPSYCHOLOGICAL CHANGES FOLLOWING SHUNT TREATMENT IN THE EUROPEAN MULTICENTRE STUDY ON INPH Hellström P., Klinge P., Tans J., Wikkelsø C. Institute of Neuroscience and Physiology, Göteborg University, Sweden O45. CHARACTERIZATION OF URINARY INCONTINENCE IN PATIENTS WITH NORMAL PRESSURE HYDROCEPHALUS (NPH) Klausner A.P.2, Aygok G.A.1, Young H.F.1, Boling P.A.3, Wolfe L.2, Koo H.P.2, Marmarou A.1 (1) Department of Neurosurgery, Medical College of Virginia Commonwealth University, Richmond, VA, USA (2) Department of Urology, Medical College of Virginia Commonwealth University, Richmond, VA, USA (3) Department Internal Medicine, Medical College of Virginia Commonwealth University, Richmond, VA, USA O46. PROPOSAL AND EVALUATION OF A COMPUTERISED NEUROPSYCHOLOGICAL TEST BATTERY FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) Behrens A.1, Eklund A.2,3,4, Elgh E.5, J. Malm1 (1) Department of Clinical Neuroscience, Umeå University, Sweden (2) Department of Biomedical Engineering and Informatics, Umeå University, Sweden (3) Centre for Biomedical Engineering and Physics, Umeå University, Sweden (4) Department of Radiation Sciences, Umeå University, Sweden (5) Department of Community Medicine and Rehabilitation, Umeå University, Sweden O47. ASSESSING TRIAL DESIGN CHOICES IN A DEVICE-BASED AD EFFICACY STUDY: A POST HOC ANALYSIS OF CHRONIC CSF DRAINAGE Silverberg G. MD1, Saul T.1, Williams J. MD2 (1) Warren Alpert Medical School, Brown University, Providence RI, USA (2) Oxford University, Oxford, UK O48. THE VALIDITY OF JAPANESE INPH GUIDELINES IN A PROSPECTIVE STUDY OF INPH (SINPHONI) Hashimoto M.1, Ishikawa M.2, Mori E.3, Kuwana N.4 (1) Noto General Hospital, Japan (2) Rakuwakai Otowa Hospital, Japan (3) Touhoku University Graduate School of Medicine, Japan (4) Tokyo Kyosai Hospital, Japan 10:30 – 10:50 Session X

10:50-13:00

Break with exhibitors

NPH and shunts

Moderators Mark Luciano, Konstantinos Polyzoidis Oral presentations

O49. ATRIAL SHUNTS – NEUROSURGICAL ATAVISM OR ESSENTIAL SECOND-CHOICE PROCEDURE? Aschoﬀ A., Sakowitz O., Dictus C., Haux D., Steiner-Milz H. Department of Neurosurgery, University of Heidelberg, Germany

Final Programme

O50. DIVERSE MORPHOLOGY IN ARACHNOID CYSTS INDICATES DIFFERENT EMBRYOLOGICAL ORIGIN Rabie K.MD3, Tisell M. MD PhD2, Högfeldt M. MD2, Wikkelsø C. MD PhD3, Johansson BR. MD PhD1 (1) Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Sweden (2) Department of Neurosurgery, Sahlgrenska Academy, University of Gothenburg, Sweden (3) Department of Neuroscience, Sahlgrenska Academy, University of Gothenburg, Sweden O51. CONSERVATIVE VERSUS SURGICAL TREATMENT OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Toma A., Papadopoulos M., Stapleton S., Kitchen N., Watkins L. O52. AMPLITUDES OF ICP PULSATIONS IN A WIDE PRESSURE RANGE Qvarlander S. MSc1, Malm J. MD PhD2, Eklund A. PhD1,3 (1) Department of Radiation Sciences, Umeå University, Sweden (2) Department of Clinical Neuroscience, Umeå University, Sweden (3) Department of Biomedical Engineering, Umeå University Hospital, Sweden O53. SYMPTOMS AND SIGNS IN 158 PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Tullberg M. MD PhD, Skagervik I. MD, Edsbagge M. MD, Hellström P. MSc, Blomsterwall E. RPt MSca, Wikkelso C. MD PhD Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden O54. TEN YEARS OF EXPERIENCE WITH THE USE OF PROGRAMMABLE AND FIXED PRESSURE VALVES. A RETROSPECTIVE COMPARATIVE STUDY OF 159 PATIENTS Gatos H., Mpakopoulou M., Paterakis K., Fountas K. Department of Neurosurgery, University Hospital of Larisa, School of Medicine, University of Thessaly, Larisa, Greece O55. A 25-YEAR-SERIES OF 700 PATIENTS WITH GRAVITATIONAL VALVES Vienenkoetter B., Haux D., Jung C.S., Unterberg A., Dictus C., Aschoﬀ A. Department of Neurosurgery, University of Heidelberg, Germany O56. SUBDURAL OR INTRAPARENCHYMAL PLACEMENT OF LONG-TERM TELEMETRIC ICP MEASUREMENT DEVICES? Schmitt M., Eymann R., Antes S., Kiefer M. Department of Neurosurgery, Medical School, Saarland University, Homburg-Saar, Germany O57. VENTRICULOATRIAL (VA) SHUNT CAN IMPROVE SAFELY HIGHER CORTICAL FUNCTION IN THE PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) Kiyoshi Takagi1,2, Katsuhiko Takeda3 (1) Department of Neurosurgery, Chiba-Kashiwa Tanaka Hospital, Japan (2) Department of Neurosurgery, Fujita Health University, Japan (3) Department of Neurology, Mita Hospital, International University of Health and Welfare, Japan O58. VIRCHOW-ROBIN SPACES IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS: A SURROGATE IMAGING MARKER FOR MICROVASCULAR DISEASE? Tarnaris A., Tamangani J., Fayeye O., Murphy H., Kombogiorgas D., Gan Y.C., Flint G. O59. BRAIN CT SCAN INDEXES IN THE NORMAL PRESSURE HYDROCEPHALUS: PREDICTIVE VALUE IN THE OUTCOME OF PATIENTS AND CORRELATION TO THE CLINICAL SYMPTOMS Stamatiou S., Chatzidakis E., Fratzoglu M., Barkas K., Markellos A., Voidonikolas L., Kyriakou T. Department of Neurosurgery, General State Hospital of Nikaia, Piraeus, Saint Panteleimon, Greece

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O60. PROSAIKA - PROGRAMMABLE SHUNTASSISTANT IN INITIAL CLINICAL APPLICATION. DESIGN OF A PROSPECTIVE MULTICENTER STUDY Kehler U.1, Kiefer M.2 (1) Department of Neurosurgery, Asklepios Klinik Hamburg-Altona, Germany (2) University Homburg/Saar, Germany O61. BRAIN LOCALIZATION OF LEUCINE-RICH Α2 GLYCOPROTEIN AND ITS ROLE Nakajima M.1, Miyajima M.1, Ogino I.1, Hagiwara Y.2, Arai H.1 (1) Department of Neurosurgery, Juntendo University School of Medicine, Japan (2) Department of Pathology and Oncology, Juntendo University, School of Medicine, Japan 13:00-13:30

Summary of the accomplishments of the meeting Harold L. Rekate, Kostantinos Kouzelis, Michael Pollay

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Oral Presentations (O) O01. QUALITY AND SAFETY OF HOME ICP MONITORING COMPARED TO IN-HOSPITAL MONITORING Andresen M., Juhler M., Munch T. Clinic of Neurosurgery, Copenhagen University Hospital, Denmark INTRODUCTION: ICP monitoring sessions are usually conducted in-hospital using a stationary device, placing restrictions of mobility for the duration of the test. Modern mobile ICP monitoring systems present new monitoring possibilities closely resembling the patients’ daily life. This study compared patient safety, quality of technical data and adequacy for clinical evaluation in ICP monitoring in the home setting versus in-hospital monitoring. MATERIALS AND METHODS: We prospectively included all ICP monitoring sessions from June 2007 – November 2009 since a new monitoring device was introduced. Patients were divided into two subgroups (home or hospital monitoring) based on clinical assessment by the attending physician. We reviewed technical curve quality and clinically useful parameters for both subgroups. RESULTS: Forty-four patients (age 1–55, mean 16,26) were included, with 50 monitoring sessions (home/in-hospital monitoring: 21/29). No difference was found in technical curve quality when comparing number of interruptions (p = 0,22), percentage of measurement duration with valid curve (p = 0,57), or in the ability to perform adequate clinical evaluation of the data (p = 0,52). No clinically detectable complications were encountered in either group. DISCUSSION: We propose home-ICP monitoring as a feasible and safe alternative to in-hospital monitoring in select cases where the patient’s caregiver can adequately observe the patient during the monitoring session. Successful performance of home-ICP requires prior meticulous information and instruction to patient/parents. O02. PATHOPHYSIOLOGY OF BRAIN STEM LESIONS DUE TO OVERDRAINAGE Antes S., Eymann R., Schmitt M., Kiefer M. Saarland University, Medical School, Department of Neurosurgery, Homburg-Saar, Germany INTRODUCTION: Mesencephalic lesions resulting from overdraining hydrocephalus shunts typically present as Parinaud’s syndrome and parkinsonism. Contrary, peripheral facial palsy, blepharospasmus and hypersalivation have not been described as a consequence of overdrainage, yet. MATERIALS AND METHODS: During the past 10 years we have treated six patients with typical clinical signs of a dorsal midbrain syndrome (DMS) resulting from overdraining shunts. Clinical work-up included TRUFI-MRI, DaTSCAN™, parallel supra-/ infratentorial ICP-monitoring and r-CBF measurement. RESULTS: Classical DMS symptoms and paraspastic occurred in all patients. Vigilance, short-term memory and endocrine functions were affected in five patients while hypersalivation combined with peripheral facial palsy and blepharospasmus have been diagnosed in one patient each respectively. Decreased vigilance state, parkinsonism and Parinaud’s syndrome result from direct mesencephalic lesion in the tentorial notch. Endocrine- and short-term memory dysfunction occur when upward-herniation of the midbrain and concomitant secondary aqueductal stenosis have been so strongly consolidated that even later underdrainage cannot restore normal anatomy. Rather third ventricle enlarges and affects mamillary bodies and hypothalamic structures. Blepharospasmus, hypersalivation and peripheral facial palsy can be explained as direct lesions of the nucleus sensorius 36

Oral Presentations (O)

principalis nervi trigemini (N.V1), inferior and superior salivary nuclei (N. IX, N.VII) and the motor strip of N.VII due to its superficial location on the IV. ventricle’s floor if its outlets are structurally or functionally occluded with tetraventricular hydrocephalus or IV. ventricle’s entrapment. DISCUSSION: Beside classical symptoms of DMS, further upper or lower brain stem lesions can occur if secondary aqueductal stenosis or IV. ventricle’s outlet obstructions aggravate this seldom overdrainage consequence. O03. INAPPROPRIATELY LOW-PRESSURE (NEGATIVE-PRESSURE) HYDROCEPHALUS: EXPERIENCE WITH 20 PATIENTS Hamilton Μ., MDCM, FRCSC Department of Clinical Neurosciences, Division of Neurosurgery, University of Calgary, Canada INTRODUCTION: Most patients with acute hydrocephalus have ventriculomegaly and high ICP. However, there is a subset of patients who are symptomatic with acute ventriculomegaly and inappropriately low ICP. MATERIALS AND METHODS: Two patient groups are presented. Each patient experienced clinical deterioration that included a significant decrease in level of consciousness with new and significant ventriculomegaly. Group 1 patients (n=10) were managed without endoscopic third ventriculostomy (ETV). Group 2 is a series of patients (n=10) managed with ETV. RESULTS: Treatment for both groups involved insertion of an EVD with ICP < 5 cm H2O. Further treatment consisted of either neck wrapping with a tensor bandage, and/or lowering the EVD to negative levels to facilitate drainage of CSF, which resulted in clinical improvement, and resolution of ventriculomegaly. All 20 patients had obstruction to CSF flow into the subarachnoid space (SAS). Group 1 patients were treated until shunt revision/insertion was possible (n=7), ICP normalized and the EVD could be removed (n=2), or death (n=1). Patients in Group 2 all underwent ETV and ICP patterns normalized in all. Group 2 patients were managed with an EVD until shunt revision/ insertion was required (n=2), ICP normalized and the EVD could be removed (n=7), or death (n=1). DISCUSSION: Inappropriately low-pressure acute hydrocephalus is an important entity in both children and adults. A possible hypothesis invokes loss of an effective subarachnoid space (SAS). ETV reestablishes communication between the SAS and ventricles producing a rapid return of normal ICP patterns and a significant decrease in the number of shunt-dependant patients. O04. ADULTS TREATED FOR INFANTILE HYDROCEPHALUS – A VERY LONG TERM FOLLOW-UP STUDY Persson E.K. MD PhD, Lindquist B. PhD, Fernell E. MD PhD, Uvebrant P. MD PhD Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Sweden INTRODUCTION: Shunt treatment of hydrocephalus started in the 1960s. This is a very long term follow-up of children born and treated in 1967-78. It is the first population based study that reports the quality of life (QoL) and long term clinical and cognitive outcome. MATERIALS AND METHODS: Of the population-based series of 72 shunt-treated children participating in a clinical follow-up study in the early 1980s, 43 had an IQ over 73. Twenty-eight of the 43 (mean age 35 years) accepted to participate in a clinical interview and to answer a questionnaire on QoL, 25 also agreed to a cognitive assessment with WAIS-III. The semi-structured interview focused on health, medical problems, shunt complications, employment and living conditions. RESULTS: The majority (26/28) were born at term. All but three individuals had experienced some kind of shunt problems. Motor dysfunction (including cerebral palsy) was present in 12 (41%), five 37

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 (18%) had epilepsy and 9 (31%) visual impairments. Seventeen (61%) individuals had finished upper secondary school, 18 (64%) worked full time and 19 (68%) were living with a partner. They rated themselves normal on most QoL-items except on vision and mental functions. Eighteen (75%) of 24 fully tested had a normal full scale IQ (90-109, median 99), three (13%) had a result in the lower normal area (80-89) and three (13%) had an IQ above 109. DISCUSSION: This group of normally gifted early shunt-treated adults performs very well cognitively, medically, socially and reported a good quality of life. It is important to consider that nowadays children born very preterm constitute a significant proportion of those with hydrocephalus and this kind of study needs to be performed also in that population. O05. MEDICATION OVERUSE AS A CAUSE OF CHRONIC HEADACHE IN SHUNTED HYDROCEPHALUS PATIENTS Juhler M., Willer L., Jensen R.H. Department of Neurosurgery, Rigshospitalet, Denmark The Headache Research Centre, Glostrup Hospital, Denmark INTRODUCTION: Some shunt patients suffer from chronic headache and continue to complain of chronic refractory headache despite intense medical effort, a shunt in perfect working order, several admissions or outpatient contacts and surgical revisions without certain findings of mechanical shunt failure. This relatively small group utilizes a disproportionally large amount of resources and their quality of life is seriously affected. We have identified medication overuse as a cause in such cases and describe the positive effect of medication withdrawal. MATERIALS AND METHODS: Patients with hydrocephalus and shunt referred from the neurosurgical department to The Danish Headache Centre were identified. In all cases over- and underdrainage was ruled out prior to referral. We used the ICDH-II definition of chronic headache. RESULTS: The table shows hospital admissions and shunt revisions before and after medication withdrawal. Values averaged pr. year over the last 3 years before withdrawal and as an average pr. follow-up year after withdrawal. * P< 0.05 using the Wilcoxon test. Furthermore, improvement of headache intensity was found in three out of six patients and a reduction in headache duration was found in two out of six patients. DISCUSSION: This study indicates that it is important to identify shunt-patients with persistent chronic headache from other causes than shunt malfunction. By reducing their analgesic intake, it is possible to reduce headache, number surgical interventions and hospital contacts. Hopefully this will raise awareness and lead to further research on the subject. Age at withdrawal

Annual number of operations before vs after withdrawal

Number of ICP measurements before vs after withdrawal

Number of hospital admissions before vs after withdrawal

Number of days admitted to hospital before vs after withdrawal

Number of out-patient contacts before vs after withdrawal

2.7

16.3

1.3

0.4

9.3

1.2

9.2

0.8

1.3

3.3

18.3

2.7

0.5

1.5

1.3

1.1

15.7

11.3

3.7

1.6

1.7

3.3

20.7

7.5

1.3

0.3

0.7

0.2

1.3

0.9

33.8

2.3

0.6*

1.2

0.07*

3.6

0.6*

20.5

4.7*

2.8

0.9*

Mean values

Oral Presentations (O)

O06. TREATMENT OF PREMATURE CHILDREN WITH POSTHEMORRHAGIC HYDROCEPHALUS BY TEMPORARY METHODS OF ICP NORMALISATION Zinenko D., Vladimirov M., Hafizov F. Moscow Pediatric and Children Surgery Research Institute, Russia INTRODUCTION: Posthemorrhagic hydrocephalus in premature children manifest on the second week of life when most of them are sick, have artificial breathing and big amount of blood inside the skull. All this factors limits neurosurgical activity in inserting shunts. To prevent secondary damage of the brain with increased ICP temporary methods, such as punctures, external and ventriculosubgaleal drainage (V-S), subcutaneous reservoirs and conservative treatment, are used. But optimal treatment remains controversial. MATERIALS AND METHODS: 305 premature children with posthemorrhagic hydrocephalus were treated during 1997-2009years in our clinic. 151 patients were treated with diuretics, subcutaneous reservoirs, external drainage and ventricular punctures. In second group (154 children) patients with communicating hydrocephalus were treated with LP and with occlusive form by inserting of V-S drainage. RESULTS: In the first group results were insufficient - ventricular punctures, diuretics and subcutaneous reservoirs didn’t allow to achieve stable normalization of ICP and had 29% of complications. In second group LP was used in communicated cases and avoid shunts in 34, 8%, and in 65,2% to win time necessary to prepare patients for shunt surgery. V-S drainage was used in occlusive hydrocephalus and in 14,2% avoid shunts, and in 85,8% normalize ICP for 18,5 days (average). If it was not enough we insert V-S drainage 2-4 times. After LP we had no and after V-S only 3% of complications. DISCUSSION: Our experience showed that best methods for temporary normalization of ICP in premature children with posthemorrhagic hydrocephalus are LP in communicating and V-S drainage in occlusive form of hydrocephalus. O07. SHUNT SURGERY CAN BE AVOIDED IN MOST PATIENTS WITH BENIGN INTRACRANIAL CYSTS Högfeldt M.1, Tisell M.1, Hellström P.2, Edsbagge M.2, Wikkelsö C.2 (1) Department of Neurosurgery, Sahlgrenska University Hospital Gothenburg, Sweden (2) Department of Neurology, Sahlgrenska University Hospital Gothenburg, Sweden INTRODUCTION: Benign intracranial cysts are treated with either shunt surgery which has a high risk of long term complications or microsurgical fenestration. Despite several studies regarding the management of intracranial cysts the question of indication and choice of surgical procedure still remains controversial in the management of this heterogeneous patient group. The objective of this study was to examine the effectiveness of microsurgical fenestration. MATERIALS AND METHODS: During a 5-years period (2003 to 2008), 142 patients with de-novo cysts were included in this prospective, consecutive case-control study. All patients with symptoms that considered to be caused by their cyst and without present surgical contraindications were offered surgical fenestration of the cyst. The follow-up included clinical, neuropsychological and radiological investigations at three months and at one year for surgically treated patients and at one year for conservative treated patients. RESULTS: 142 patients were examined. After evaluation 69 patients were considered to have symptomatic cysts. 41 females and 28 males (mean age 41, range 0,5-80) were operated with microsurgical fenestration as firsthand surgery. After fenestration two patients had remaining symptoms and were shunted; one had multiple cysts and one had concomitant hydrocephalus. 39

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 DISCUSSION: Microsurgical fenestration is effective in treating patients with symptomatic benign intracranial cysts. Only two of the 69 operated patients eventually needed secondary shunt surgery after a minimum follow-up of one year. O08. ASYMPTOMATIC TREATMENT FAILURE IN PEDIATRIC HYDROCEPHALUS - FEATURES OF AN UNDER-DIAGNOSED (?) ENTITY Schuhmann M. U.1, Speil A.2, Haas-Lude K.2, Alber M.2, Bevot A.2 (1) Section of Pediatric Neurosurgery, Department of Neurosurgery, Eberhard Karls University Hospital, Tuebingen, Germany (2) Department of Pediatric Neurology, Eberhard Karls University Children‘s Hospital, Tuebingen, Germany INTRODUCTION: It is common belief, that shunt/ETV failure is associated with symptoms/signs of raised ICP. Are those absent, especially in children with developmental delay or behavioral problems, shunt/ETV failure might remain undiagnosed or considered not relevant. In reality, children might suffer subclinical damage from uncompensated intracranial CSF dynamics. We report on imaging features and ICP monitoring results of asymptomatic patients, in whom shunt blockage/ETV reclosure was confirmed. MATERIALS AND METHODS: Patients were critically re-evaluated for treatment failure by careful clinical assessment, followed by high-resolution MRI and/or computerized overnight ICP-analysis/ shunt infusion study. If the suspicion of shunt/ETV malfunction and uncompensated CSF dynamics could be substantiated, children underwent repeat surgery. RESULTS: We identified 15 children with suspected treatment failure. In 5 with large ventricles or migrated catheters, ICP overnight monitoring showed the same pathognomonic features of shunt malfunction (baseline ICP>15mmHg, peak ICP>25mmHg, RAP>0.6) as we found previously in symptomatic patients. In 5 children ICP recordings were normal. There was a pathological and a normal shunt infusion study, respectively. In 3 children post ETV, ICP recordings were pathological. At surgery, a blocked shunt or closed ETV was found. DISCUSSION: Asymptomatic treatment failure in hydrocephalic children seems to the more common the more thorough children are evaluated. A hallmark in non-gravity assisted shunt systems is the failure of ventricles to get significantly smaller. High-resolution MRI can detect scarring around the shunt tip or ETV re-closure. ICP overnight monitoring or shunt infusion study are excellent diagnostic tools, since shunt-failure has characteristic patterns. O09. THE MANAGEMENT AND THE OUTCOME OF INTRAVENTRICULAR HEMORRHAGE IN BABIES WITH LOW BIRTH WEIGHT Inagaki T.1, Kawamoto K.2, Kinoshita Y.3 (1) Pediatric Neurosurgery, Kansai Medical University, Japan (2) Neurosurgery, Kansai Medical University, Japan (3) Pediatrics, Kansai Medical University, Japan INTRODUCTION: Intraventricular hemorrhage and posthemorrhagic hydrocephalus are common causes of neonatal morbidity and mortality among preterm and low-birth weight infants. The management of posthemorrhagic hydrocephalus is difficult and not well standardized. In this study, we aimed to determine the incidence of hydrocephalus after intra ventricular hemorrhage and the associated risk factors for surgical intervention in those patients.

Oral Presentations (O)

MATERIALS AND METHODS: Eighteen patients were diagnosed as intraventricular hemorrhage during the period between January 1998 to September 2005. The number of the patients admitted to our institute was 1346 at the same period. The survivors were followed more than five years. RESULTS: Six out of 18 patients required the surgical treatment. There was correlation between the Papille grading and the outcome. The most risk factor for V-P shunt was the severity of IVH. The patients who required any surgical management tended to stay in the hospital longer than the others. DISCUSSION: In this study, we presented the strategy of the management of intraventricular hemorrhage in patients with low birth weight. Low birth weight children with severe intraventricular hemorrhage that requires surgical management are at greatest risk for adverse neurodevelopmental and growth outcomes. O10. SLOW VASOGENIC FLUCTUATIONS OF INTRACRANIAL PRESSURE AND CEREBRAL NEAR INFRARED SPECTROSCOPY – AN OBSERVATIONAL STUDY Czosnyka Z.1, Weerakkody R. A.1, Czosnyka M.1, Balédent O.2, Souraya Stoquart El-sankari2, Pickard J.1 (1) Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK (2) Department of Medical Physics and Imaging, University of Amiens Hospital, Amiens, France (3) Department of Neurology, Cliniques Universitaires Saint-Luc, Brussels, Belgium Study partially supported by EC INTERREG (cooperation Amiens-Cambridge) grant INTRODUCTION: Increased slow wave activity in intracranial pressure (ICP) signifies an exhausted cerebrospinal compensatory reserve across a range of conditions including hydrocephalus, craniosynostosis and cerebral oedema of various aetiologies. Their underlying physiological basis remains unclear. In this study we describe synchronisation between slow waves of ICP and of near infrared spectroscopy (NIRS) variables induced by controlled elevation of ICP during an infusion study. MATERIALS AND METHODS: Nineteen patients presenting with symptomatic hydrocephalus underwent a diagnostic intraventricular constant-flow infusion test. During the infusion test NIRSderived indices, including deoxygenated, oxygenated and total haemoglobin (Hb, HbO2, HbT), tissue oxygenation and haemoglobin indices, ICP and arterial blood pressure (ABP) were recorded simultaneously. RESULTS: ICP increased from 9.3(6.0) mmHg to a plateau of 17.1(8.9) mmHg (P < 5 x 10-9) during infusion. Slow waves in ICP were accompanied by concurrent waves in Hb, HbO2, HbT, TOI and THI of the same periodicity. The mean coherence between NIRS variables and ICP slow waves was > 0.7, with no significant phase shift. In the same frequency range, ABP fluctuations occurred with a coherence of 0.77 and phase lead of 40o with respect to ICP. The power of ICP slow waves increased significantly from baseline to infusion plateau which correlated with a corresponding increase in power of Hb waves. DISCUSSION: Slow waves in ICP seen in hydrocephalic patients coincide with fluctuations of Hb and HbO2 detected with NIRS.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O11. WHO NEEDS A SHUNT? CSF DYNAMICS PERSPECTIVE Czosnyka M.1, Schuhmann M.2, Werrakody R.1, Keong N.2, Santarius T.1, Schmidt EA.4, Balédent O.1, Pickard JD.1, Czosnyka Z.1 (1) Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK (2) Department of Neurosurgery, University of Tuebingen, Germany (3) Department of Medical Physics and Imaging, University of Amiens Hospital, France (4) Neurosurgery, Hopital Pourpan, Toulouse, France Study partially supported by EC INTERREG (cooperation Amiens-Cambridge) grant INTRODUCTION: The term ‘hydrocephalus’ encompasses a range of disorders characterised by clinical symptoms, abnormal brain imaging and derangement of CSF dynamics. Is this description, neglecting ‘vascular factors’, complete? Is improvement in CSF circulation always equivalent to clinical improvement? MATERIALS AND METHODS: Cerebrospinal compensatory reserve have been studied from 2665 CSF infusion tests and 305 overnight ICP-monitoring sessions performed in 1423 patients over a 17 year period. Parameters describing CSF dynamics as derived by infusion testing include: baseline ICP, pulse amplitude of ICP, elasticity, resistance to CSF outflow and power of slow vasogenic waves in ICP. In addition, a derived index called RAP, provides an insight into cerebrospinal compensatory reserve. RESULTS: We demonstrate how variables: resistance to CSF outflow, pulse amplitude of ICP waveform, RAP index and slow vasogenic waves may be used to differentiate clinically overlapping entities with disturbed and normal CSF dynamics. Similarly, in shunted patients, CSF compensatory variables allow the detection of shunt malfunction (partial or complete blockage) or overdrainage. The presence of an increased RAP, increased frequency and amplitude of slow waves vasogenic waves at normal baseline ICP are a hallmark of exhausted cerebrospinal compensatory reserve and may be detected by overnight ICP monitoring. DISCUSSION: This observational study is intended to serve as an update for our understanding of quantitative testing of cerebrospinal dynamics using the CSF infusion test and overnight ICP monitoring. We still cannot be sure if, when correcting CSF dynamics, we always improve clinical status of our patients. O12. SIMULATION OF SHUNT VALVES IN A HYDROCEPHALUS MODEL Krause I.1, Walter M.1, Kiefer M.2, Leonhardt S.1 (1) Chair for Medical Information Technology, Helmholtz-Institute, RWTH Aachen, Germany (2) Neurosurgery, Saarland University, Medical School, Homburg-Saar, Germany Hydrocephalus, a challenging illness of the brain, has been evaluated by several models before. However, the effect of a shunt has not been considered within these models. In this work, an adapted version of Ursino’s model is extended to include the effect of shunt valves on overall cerebrospinal fluid (CSF) dynamics. The behaviour is examined in simulations. A Matlab Simulink model is proposed which incorporates the effect of cerebral blood flow through four compartments (namely arteries, arterioles, capillaries and veins), autoregulation, oxygen and carbon dioxide partial pressures, pathological changes in the elastance coefficient and CSF outflow resistance. Key features of previous test rig measurements of shunts are integrated in the shunt model. During the simulation, the effect of the shunt on P-, B- and A-waves are explored. The simulation of the model clearly shows that the shunt lowers the intracranial pressure (ICP). P- and B-waves still 42

Oral Presentations (O)

exist but at a lower ICP level and because of the exponential P-V curve also with considerably lower amplitude. Because the valve drains enough liquor, A-waves cannot develop. The resulting ICP is above the opening pressure depending on the drain and the resistance of the shunt. This simulation confirms the hypothesis that a shunt can indeed prevent the dangerous A-waves. With reduced ICP baseline the amplitude decreases as well. Up to know, no in vivo shunt parameters of flow and pressure exist. This simulation allows the analysis of the behaviour of the shunt in interaction with ICP and cerebral hemodynamics. O13. REALISTIC PHANTOM OF CRANIO-SPINAL HYDRODYNAMICS Bouzerar R.1, Czosnyka M.2, Czosnyka Z.2, Balédent O.1 (1) Department of Medical Physics and Imaging, University of Amiens Hospital, Amiens, France (2) Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK INTRODUCTION: Inside the cranio-spinal system, CSF and blood compartments interact in order to stabilize cerebral blood flow, volume and avoid unstable ICP. Blood and CSF interactions occurring through volume exchanges are still not well understood. Using our experience from human ICP recordings, cerebral blood and CSF flow measurements; we constructed a realistic phantom of the global cranio-cerebral fluid dynamics. The objective of this work is to study experimentally, in strictly controlled conditions, the hydrodynamic mechanisms underlying pathogenesis of hydrocephalus. MATERIAL AND METHODS: A polycarbonate structure representing the cranium is connected to the spinal channel ended with a specific compliance. The cranium is divided into various compartments, mimicking the simplified anatomical regions as ventricles and aqueduct cerebri. Resistances and compliances of blood and CSF compartments can be assessed or measured using the pressure and flow sensors incorporated in the model. Realistic arterial blood flow is generated by a numerically programmable pump. The flows and pressures inside the system are simultaneously recorded. RESULTS: The preliminary results show that the model can mimic venous and CSF flows in response to arterial pressure input. The experimentally measured intracranial pressure is directly influenced by the choice of deformable structures used to simulate veins and dural sac. Propagation of pulse waveforms and volume flows were simulated and the results partially replicated the data previously obtained with Phase-Contrast MRI. DISCUSSION: ICP measurements show that the model verifies a Marmarou’s relationship between pressure and intracranial volume expansion. The phantom will be useful to investigate hydrodynamics mechanisms of hydrocephalus. O14. CSF DYNAMIC PROFILE OF POTENTIAL SHUNT CANDIDATES IN COMPARISON WITH HEALTHY ELDERLY Frankel J. MSc1, Eklund A. PhD1,2, Malm J. MD PhD3 (1) Department of Biomedical Engineering, Umeå University Hospital, Sweden (2) Department of Radiation Sciences, Umeå University, Sweden (3) Department of Clinical Neuroscience, Umeå University, Sweden INTRODUCTION: The presumed typical CSF dynamic profile (i.e., increased pulsations, outflow resistance and ICP) of NPH has never been validated against age-matched healthy subjects. The objective was to compare CSF dynamic parameters in healthy elderly to patients with ventriculomegaly and gait or cognitive disturbances (“suspected NPH”), admitted to a tertiary hydrocephalus center for preoperative investigation.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 MATERIALS AND METHODS: Forty-one healthy subjects (mean age 70 yrs; 56% women) and 66 consecutive patients investigated for “suspected NPH” (73 yrs; 33% women) were included. All were investigated with a lumbar infusion method. ICP (at rest), outflow resistance and the pulsation amplitude of the pressure at resting level were analyzed. The parameter means were compared in two-sample t-tests. RESULTS: The difference in mean ICP between the two groups, 0.33 mmHg, was not significant (p=0.491), whereas the difference in mean outflow resistance, 6.17 mmHg/(mL/min), was (p<0.001). The mean pulsation amplitude differed slightly between the two groups, 0.37 mmHg, but the difference was not statistically significant (p=0.175). DISCUSSION: The comparison with healthy elderly revealed that typical patients investigated for NPH had normal pressure, possibly with slightly increased pulsation amplitudes. The expected disturbed CSF-dynamics was primarily confirmed through an elevated outflow resistance. Overlap for all distributions suggests that a more complex model than a single parameter will probably be needed to separate between healthy and NPH patients, and ultimately between shunt responders and non-responders. O15. ESTIMATION OF OUTFLOW RESISTANCE – MODEL DEPENDENCY Eklund A. PhD1,2, Andersson K. MSc2, Malm J. MD PhD3 (1) Department of Biomedical Engineering, Umeå University Hospital, Sweden (2) Department of Radiation Sciences, Umeå University, Sweden (3) Department of Clinical Neuroscience, Umeå University, Sweden INTRODUCTION: The CSF-absorption is described by the Davson equation which states that the net absorption is equal to the difference between ICP and venous pressure divided by outflow resistance (Rout). Rout is accordingly determined by estimating the slope between flow and pressure at a number of increased pressure levels, or by estimating the pressure increase from baseline resting pressure (Pr) from a constant inflow. Main difference between these methods is if they use Pr or not in their model. The aim of this analysis was to compare Rout (or outflow conductance Cout) estimates based on models with or without Pr. MATERIALS AND METHODS: A constant pressure infusion investigation with six elevated pressure levels was performed on 86 subjects. Model without Pr: Rout was calculated from linear regression based on the six pressure-flow points. Model with Pr: flow from all six static levels was averaged into one pressure and flow point. Rout was then calculated as the pressure difference between that point and Pr, divided with the mean flow. RESULTS: The difference in Rout was 1.44±6.8 mmHg/ml/min (mean±SD, p=0.02), with a lower Rout for the Pr -model. Corresponding values for Cout was -1.72±3.2 ul/s/kPa (p<0.001). The correlation between the methods was 0.68 for Rout and 0.81 for Cout. DISCUSSION: Although there was a good general agreement, for some patients there was a distinct difference causing a reduced correlation. When comparing results between studies and for setting thresholds for prediction this will be important. We should aim for standardization. The physiological background behind these findings should be further investigated.

Oral Presentations (O)

O16. ENDOSCOPIC IIIRD VENTRICULOSTOMY (ETV). SURGICAL TECHNIQUE AND PITFALLS Bouramas D.1,2, Paidakakos N.2, Sotiriou F.1, Kouzounias K.1, Sklavounou M.2, Gekas N.1 (1) Department of Neurosurgery, Athens Naval Hospital, Greece (2) Department of Neurosurgery, Athens Bioclinic, Greece INTRODUCTION: Our experience in the variety of pathological entities causing obstructive hydrocephalous is being reported, and the effectiveness of endoscopic treatment is being evaluated, with particular attention to surgical technique and pitfalls. MATERIALS AND METHODS: We reviewed the cases of 57 consecutive patients (43-89 years old) treated with ETV in the last 9 years. The etiology of the hydrocephalus was benign aqueductal stenosis (30 cases), tumors (15), intraventricular cysts (5), intraventricular or subarachnoid hemorrhage (4) and post-infection aqueductal stenosis (3). All patients were evaluated with MR and phase contrast cine MR scans both pre- and postoperatively. The authors used a rigid endoscope to perform a blunt fenestration of the third ventricle floor. A septostomy was also performed in 10 cases. The follow up period ranged from 4 to 36 months. Operative videos were also reassessed and surgical nuances reconsidered. RESULTS: ETV was accomplished in all but 3 cases. The overall rate of good results (shuntindependent patients with clinical remission or improvement) was 81.5% (44/54). From 10 patients with ETV failure 5 were re-ETVed successfully and 5 were shunted. Patients with benign aqueductal stenosis and tumor compressing the aqueduct had the greatest profit from the ETV. There were no permanent morbidities or mortalities. Complications were venous bleeding in three cases, and intracerebral bleeding in one case. 3 patients had transient memory loss. DISCUSSION: ETV for obstructive hydrocephalus of various origins is safe and effective, and should be considered as a first line treatment. Familiarity with the ventricular anatomy and its variations in hydrocephalus is key to success. Preoperative planning is mandatory. Ο17. CHANGES OF FRACTIONAL ANISOTROPY (FA) AND APPARENT DIFFUSION COEFFICIENT (ADC) IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Mase M.1, Demura K.1, Osawa T.1, HattoriI M.2, KasaiI H.3, Miyati T.4, Yamada K.1 (1) Department of Neurosurgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan (2) Department of Neurology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan (3) Department of Radiology, Nagoya City University Hospital, Nagoya, Japan (4) Faculty of Health Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan INTRODUCTION: Since ventricular dilation and periventricular abnormal intensities on MR (magnetic resonance) images are commonly seen in patients with idiopathic normal pressure hydrocephalus (iNPH), dysfunction of white matter may have an important role for the mechanism causing symptoms of iNPH. In order to clarify the pathophisiology of iNPH, we analyzed axonal water dynamics using diffusion tensor MR imaging (DTI). MATERIALS AND METHODS: 36 patients with possible iNPH were included. Regional fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were measured bilaterally in the frontal periventricular region, the posterior limb of the internal capsule, corona radiata, centrum semiovale, and corpus callousm before and 24 hours after a cerebrospinal fluid tap-test (CSF-TT; withdrawal of 30ml of CSF by a lumbar puncture). The patients were divided into two groups; patients showed 45

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 significant improvements in neurological status after the CSF-TT (CSF-TT positive, n=17), and no neurological improvement (CSF-TT negative, n=19). RESULTS: After CSF-TT, ADC values were significantly decreased in the frontal periventricular region and the body of corpus callosum in the CSF-TT positive group (p<0.05), whereas no significant change was shown in the CSF-TT negative group. FA values were significantly increased in the body of corpus callosum in both groups after CSF-TT (p<0.05). DISCUSSION: After CSF-TT, water molecules at the extracellular space could move to intraventricular space by reduction of the CSF in the lateral ventricle, resulting in decreased ADC values in the periventricular regions. This suggests that changes of water dynamics in white matter may have a role for mechanism causing symptoms of iNPH. O18. MR-ELASTOGRAPHY IN NORMAL PRESSURE HYDROCEPHALUS PRE- AND POSTSHUNT – EVALUATION OF A NEW IN-VIVO METHOD AND IMPLICATIONS FOR PATHOGENESIS Sprung C.1, Freimann F.B.1, Streitberger K.J.2, Wiener E.3, Sack I.2 (1) Department of Neurosurgery, Charité - University Berlin, Campus Rudolf Virchow, Berlin, Germany (2) Department of Radiology, Charité - University Medicine Berlin, Campus Charité Mitte, Berlin, Germany (3) Department of Neuroradiology, Charité - University Medicine Berlin, Campus Charité Mitte, Berlin, Germany INTRODUCTION: While several divergent theories are discussed, knowledge about pathogenesis of Normal Pressure Hydrocephalus (NPH) remains a matter of contoversy. Magnetic Resonance Elastography (MRE) allows studying in vivo alterations of viscoelastic properties of brain tissue to enlighten new aspects of NPH pathophysiology. MATERIALS AND METHODS: We compared MRE of 20 patients suffering from idiopathic (n=15) and secondary (n=5) NPH before shunt surgery with an age-matched collective of 25 healthy volunteers. Measurements were carried out with multifrequency MRE. Viscoelastic constants related to stiffness (µ) and micro-mechanical connectivity (α) of brain tissue were derived from the dynamics of storage and loss modulus within the experimentally achieved frequency range between 25 Hz and 62.5 Hz. In a second step we correlated clinical grading of Hakim`s triad with MRE-values and finally compared the µ - and α - measurements 3 months post-shunt. RESULTS: We found a decrease of elasticity (loss of stiffness) in NPH brain tissue, expressed by a roughly 20% decreased µ compared to healty volunteers (p<0,001). Alterations in micro-mechanical connectivity of brain tissue could be observed by a decrease of 9% in α (p<0,001). We did not find a clear correlation between alterations of tissue properties and clinical severity of NPH, but a tendency towards recovery of the visco-elastic properties parallel to clinical improvement postoperatively was evaluated. DISCUSSION: The results show a distinct alteration with decrease of elasticity in NPH. We conclude that MRE is capable to measure the viscoelastic changes in vivo pre- and postoperatively, thus it may elucidate the pathophysiology of NPH.

Oral Presentations (O)

O19. NEW EPENDYMAL CELLS ARE BORN POSTNATALLY AND SUPPORT VENTRICULOMEGALY IN HYDROCEPHALIC MICE Bátiz L.F.1, Jiménez A.J.2, Toledo C.D.1, Guerra M.1, Vio K.1, Rodríguez-Pérez L.M.2, Páez P.2, Pérez-Fígares J.M.2, Rodríguez E.M.1 (1) Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile (2) Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain INTRODUCTION: Ependymal cells act as a protective barrier that covers the surface of the cerebral ventricles. They are derived from radial glial cells and most of them are primarily born during embryonic stages. The extent to which mature ependymal cells can divide and self-renew postnatally is still a matter of debate. Both, the period when ependymal cells are born and the putative proliferative capacity of them gain significance under pathological conditions that involve enlargement of ventricular walls such as hydrocephalus. The aim of the present study was to investigate the adaptative changes in the ventricular zone/ependymal lining of a mouse model developing congenital hydrocephalus. MATERIALS AND METHODS: Brains of wild type (wt) and mutant (hyh) hydrocephalic mice were analyzed by light and scanning electron microscopy at various postnatal ages (P1-to-P30). Proliferative activity was studied by PCNA and Ki-67 immunostaining. Phenotype of proliferative cells was addressed in pulse or cumulative BrdU-labelling experiments using radial glíal/ependymal markers. RESULTS AND CONCLUSIONS: In wt mice, we found proliferative cells in the ventricular zone of two distinct regions: the dorsal wall of the third ventricle (3v) and the dorsal wall of cerebral aqueduct (SA). Most of the proliferative cells correspond to monociliated nestin+ cells. Cumulative BrdU-labelling experiments suggest that these cells can originate ependymal cells postnatally. Increased proliferative (ependymogenic) activity was observed in hydrocephalic animals. Thus, new ependymal cells are born postnatally from monociliated (radial glial?) precursor cells in discrete regions of the cerebral ventricles and this phenomenon is enhanced during ventricular enlargement. Furthermore, pulse BrdU-labelling or Ki-67 immunostaining showed the presence of scarce proliferative multiciliated cells. Therefore, self-renewing proliferation of mature ependymal cells should also be considered. O20. GENE EXPRESSION PROFILING OF CHOROID PLEXUS IN ALZHEIMER’S DISEASE REVEAL IMPORTANT IMPLICATIONS FOR CSF DYNAMICS Stopa E.G.1, Nikonova E.V.2, Tanis K.Q.2, Podtelezhnikov A.A.2, Finney E.M.2, Stone D.J.2, Camargo L.M.2, Parker L.2, Verma A.2, Baird A.3, 4, Miller M.C.1, Donahue J.E.1, Gonzalez A.M.4, Eliceiri B.3, Silverberg G.D.1, Klinge P.M.1, Johanson C.E.1 (1) Departments of Neurosurgery and Pathology (Neuropathology Division), Rhode Island Hospital, The Warren Alpert Medical School, Brown University, Providence, RI, USA (2) Molecular Profiling & Research Informatics, Merck Sharp & Dohme, West Point, PA, USA (3) Department of Surgery, University of California San Diego Medical Center, San Diego, CA, USA (4) School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, UK In aging, NPH, and Alzheimer’s disease (AD) there are changes in CSF composition related to altered choroid plexus (CP) function. Human Affymetrix 48K gene arrays were used to determine diseaserelated changes in gene expression within CP. Tissue samples from control (age/PMI: 58 years/22 47

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 hours) and patients with advanced (Braak V-VI) AD (79/18) were snap-frozen and stored at -80°C. Diseased control samples with frontotemporal dementia (72/NA) and Huntington’s disease (71/19) were also collected. RNA was extracted using Trizol followed by NuGEN Ovation amplification. cDNA was hybridized to custom chips at Rosetta/Merck. After RMA normalization, the data was analyzed using one-way ANOVA. Significant gene sets were further analyzed for biological enrichment using individual (Ingenuity) and combined (Target and Gene Information System) pathway tools. Clear differences were observed in gene expression levels in CP of AD patients relative to normal and diseased controls. 648 sequences could significantly separate four experimental groups (p<0.001, FDR~8%). Half were upregulated in neurodegenerative diseases. The upregulated genes represented 15 highly-enriched biological functions (multiple correction Expectation value below 10E01). Strikingly, cell adhesion and extracellular matrix re-modeling along with post-translational modification (phosphorylation) were highly enriched in AD patients (E value below 10E04). A significant increase in immune response was evident in AD patients, while oxidative phosphorylation and amyloid processing were downregulated. Other observations included decreased PPARa/ RXRa nuclear receptor/retinoic acid; a-adrenergic, glucocorticoid, and melatonin signaling; as well as N-glycan, glutathione (antioxidant). and ubiquinone metabolism in AD. This unique resource is available for sharing with investigators working on aging, CSF, and hydrocephalus. O21. HYDROCEPHALUS AND AQUAPORINS. THE ROLE OF AQUAPORIN-1 Kalani MYS, Filippidis A.S., Rekate H.L. Division of Pediatric Neurosurgery, Barrow Neurological Institute, Phoenix, AZ INTRODUCTION: Aquaporins (AQPs) are membrane proteins that facilitate water and small solute movement in tissues. Hydrocephalus is a major central nervous system disorder associated with defective cerebrospinal fluid (CSF) turnover. Aquaporin-1 is a water channel located mainly at the choroid plexus epithelium and plays an active role in CSF production. The aim of this study is to review the pertinent literature concerning the role of aquaporin-1 in the pathophysiology of hydrocephalus. MATERIALS AND METHODS: We performed a MEDLINE search using the terms “aquaporin AND hydrocephalus”. The results of the search were further refined in order to exclude studies not related to aquaporin-1. RESULTS: Five studies were identified. Three of these studies utilized an animal model while only two studies referred to few human cases of hydrocephalus. Most of the studies indicate that there is a downregulation of AQP1 expression in choroid plexus in models of hydrocephalus. A small series of human choroid plexus tumors showed that AQP1 expression is upregulated. In cases of human choroid plexus tumors there are indications that AQP1 may have alternative physiologic roles but it is not clear whether this is associated with a specific type of hydrocephalus or the genetic burden of the tumor. DISCUSSION: There has been a paucity of research on the link between aquaporins and hydrocephalus. Most studies rely on animal models. An adaptive and protective role of AQP1 as a regulator of CSF production is proposed in the pathophysiology of hydrocephalus. Further research is needed in order to clarify if this association exists in humans. O22. HYDROCEPHALUS AND AQUAPORINS. THE ROLE OF AQUAPORIN-4 Filippidis A.S., Kalani MYS, Rekate H.L. Division of Pediatric Neurosurgery, Barrow Neurological Institute, Phoenix, AZ INTRODUCTION: Aquaporins (AQPs) are membrane proteins that facilitate water and small solute movement in tissues. Hydrocephalus is the major central nervous system disorder associated with 48

Oral Presentations (O)

defective cerebrospinal fluid turnover. Aquaporin-4 is a water channel located mainly at the blood-brainbarrier (BBB) and blood-CSF interfaces and is associated with the elimination of cerebral edema via these routes. The aim of this study is to review the pertinent literature concerning the role of aquaporin-4 in the pathophysiology of hydrocephalus. MATERIALS AND METHODS: We performed a MEDLINE search using the terms “aquaporin AND hydrocephalus”. The results of the search were further refined in order to exclude studies not related to aquaporin-4. RESULTS: Six studies were identified. All studies utilized an animal model like AQP4 knock-outs, H-Tx rats, and kaolin and LPS injection models of hydrocephalus. Most studies indicate that there is an upregulation of AQP4 expression at the BBB and blood-CSF interfaces in cases of hydrocephalus. One study, reported sporadic cases of obstructive hydrocephalus in a subgroup of AQP4 knock-out mice. DISCUSSION:Few publications study the association between aquaporins and hydrocephalus. Currently all the existing studies rely on animal models. An adaptive and protective role of AQP4 in order to increase the resolution of the “hydrocephalic”” edema at the BBB and blood-CSF interfaces is proposed in the pathophysiology of hydrocephalus. Further research is needed in order to clarify if this association exists in humans. O23. EXPERIMENTAL HYDROCEPHALUS INDUCES CHANGES IN CONSTITUTIVE AQUAPORIN-4 EXPRESSION AND CHANGES MORPHOLOGY OF AQUAPORIN-4 POSITIVE EPENDYMA Skjolding A.D.1, Rowland I.2, Soegaard L.V.2, Praetorius J.3, Penkowa M.4, Juhler M.1 (1) University Clinic of Neurosurgery, Rigshospitalet, Copenhagen, Denmark (2) Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital, Hvidovre, Denmark (3) The Water and Salt Research Center, Department of Anatomy, Aarhus University, Aarhus, Denmark (4) Section of Neuroprotection, Department of Neuroscience and Pharmacology, Faculty of Health Science, Copenhagen University, Copenhagen, Denmark The water channel Aquaporin-4 (AQP4) is under normal conditions expressed in astrocytes and ependymal cells. Hypothesizing that AQP4 is a future pharmacologic target, we studied the cellular expression of AQP4 in experimental hydrocephalus. Experimental hydrocephalus was induced in rats by intracisternal kaolin injection. Ventriculomegaly was confirmed by in vivo MRI. AQP4 expressing cell types were characterised by using immunohistochemistry (IHC) and double fluorescence staining for AQP4 and cell type markers: Glial fibrillary acidic protein (GFAP) for astrocytes and tomato lectin for microglia/macrophages and endothelium. Western blotting (WB) was used to quantify expression levels of AQP4. Immunohistochemistry IHC revealed changed morphology of the AQP4 positive ependyma. Fluorescence staining revealed that astroglia are the main source of AQP4 expression in the brain, while microglia and endothelial cells are devoid of AQP4 expression in both hydrocephalic rats and in controls. In hydrocephalic animals, periventricular AQP4 expression was reduced at 2 days and increased at 2 weeks indicating that AQP4 regulation could be a compensatory response. Our data confirm an astrocytic and ependymal origin of AQP4 expression during hydrocephalic brain pathology. Hydrocephalus causes extracellular edema, which in the light of the putative differential roles of AQP4, suggests future pharmacological studies of AQP4 as a drug target may be worthwhile.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O24. PRENATAL MOLECULAR DIAGNOSIS AND STEM CELL RESEARCH IN SEVERE TYPE OF L1CAM SYNDROME (X-LINKED HYDROCEPHALUS) Yamasaki M. MD PhD1,2, Nonaka M. MD PhD2, Shofuda T. MS1, Kanemura Y. MD PhD1,2 (1) Institute for Clinical Research, Osaka National Hospital, National Hospital Organization, Japan (2) Department of Neurosurgery, Osaka National Hospital, National Hospital Organization, Japan INTRODUCTION: Mutations in the gene for the neural cell adhesion molecule L1CAM (L1) are now known to be responsible for X-linked hydrocephalus (XLH). XLH show very poor outcome. Prenatal gene diagnosis is very important and there is a need to develop more effective therapeutic strategies. Here, we report prenatal gene analysis of 10 times in eight families, and will introduce our approach for studying molecular properties of stem cells derived from patients of XLH. MATERIALS AND METHODS: DNA was obtained by chorio villi aspiration or ammuniotic fluid aspiration from pregnant obligate carriers of L1 gene mutations from 10 to 16weeks gestations. Amplification of the exons and the exon-intron boundaries of the L1 gene was performed by PCR and Purified PCR amplification products were directly sequenced and analyzed with a capillary DNA sequencer. We isolated neural stem/progenitor cells (NSPCs) derived from tow autopsied patients of XLH. In vitro NSPCs of human origin can be selectively expanded in serum-free culture medium supplemented with FGF-2 and/or EGF as neurospheres, which contain a population of NSPCs. RESULTS: The ethical guideline (2003) related prenatal gene diagnosis in Japan prohibits the carrier check of childhood. Therefore in the resent cases, L1 gene analysis was not performed in the cases of female fetus. Therefore three male and three female fetuses were analyzed. A male fetus had L1 gene mutation and two male did not have. In 3 females, whose gene testing had been performed before 2003, one did not carry the mutation and two had the heterozygote mutation. Mothers who had carried male fetus with L1 gene mutation terminated their pregnancy. The other eight careers continued their pregnancy and delivered normal babies. The diagnosis was made with perfect accuracy. No maternal and fatal complication in chorionic villus biopsy was occurred. NSPCs with L1 gene mutations showed high cell proliferation rate, abnormal differentiation pattern and lack of migration ability compared with normal NSPCs. DISCUSSION: Prenatal L1gene analysis is useful and helpful for their family. Specific stem cells offer an opportunity to reproduce pathologic CNS formation in vitro, thereby giving potential to enable disease investigation and development of new treatments. O25. EFFECT OF ACETAZOLAMIDE ON AQUAPORIN-1 EXPRESSION OF CULTURED CHOROID PLEXUS CELLS Pouya Ameli, Meenu Madan, Srinu Chigurupati, Amin Yu, Sic L. Chan, Jogi V. Pattisapu Hydrocephalus Research Laboratory, University of Central Florida College of Medicine INTRODUCTION: Acetazolamide (AZA), the only drug generally approved for hydrocephalus, is effective in only 25-30% of patients, and its effect on basal fluid flow in choroid plexus (CP) is unknown. The drug reversibly inhibits Aquaporin 4 (AQP4), the most highly expressed ‘water pore’ in the brain, and it is postulated that it reduces CSF production by modulating the expression and/or function of AQP1 (mostly found in the apical membrane of CP). In this study, we sought to elucidate the direct effect of AZA on basal fluid flow in CP. MATERIALS AND METHODS: CP tissues were harvested from 10-day Sprague-Dawley rat pups. CP cultures were grown to confluence in Transwell permeable supports and tested using: a) Kir 7.1 immunocytochemistry to confirm CP cell morphology; b) Lucifer Yellow assay and trans-epithelial 50

Oral Presentations (O)

electrical resistance (TEER) to determine level of confluence; c) fluid assays using TRITC-labeled Dextran to assay the direction and extent of fluid flow through the monolayers; d) expression of AQP1 protein by immunoblotting and immunocytochemistry. RESULTS: Immunblotting and immunocytochemical analyses showed that AQP1 protein level decreases rapidly with 10 um AZA treatment. The reduction of AQP1 protein was transient as its level returned to baseline 12 hours after AZA exposure. Transwell fluid assay indicated that the early loss of AQP protein is correlated with decreased basal fluid flow in CP. DISCUSSION: The observed effect of AZA on AQP1 protein level suggests that AZA can directly modulate basal fluid flow in CP. The AZA induced effect in CP resulted in an initial fluid flow into the basolateral side of the transwells, with subsequent flow into the apical side of the CP membranes. Our results indicate that modulating AQP1 function via effectively targeted pharmaceuticals could potentially yield new treatments for hydrocephalus. O26. EXPERIENCE WITH FRONTO-TEMPORAL DEMENTIA IN PATIENTS SHUNTED FOR HYDROCEPHALUS Williams M.A., Wilson R.K., Smith C.A. Sandra and Malcolm Berman Brain & Spine Institute, Adult Hydrocephalus Center, Sinai Hospital of Baltimore, Baltimore, MD USA INTRODUCTION: To describe a single center experience of fronto-temporal dementia (FTD) in patients shunted for hydrocephalus. MATERIALS AND METHODS: We searched our patient database from July 2007 to February 2010 for the terms FTD or fronto-temporal dementia and found 44 patients, of whom 8 had a shunt. Results are shown as mean±SD. RESULTS: Sex: men-5, women-3. Age of onset: 67.0±9.1 years (range 52-76). Site of initial evaluation and shunt: Sinai-4, elsewhere-4. Hydrocephalus etiology: colloid cyst-1, possible INPH-7. Presenting signs/symptoms: gait difficulty-5/8; urinary urgency/incontinence-5/8; cognitive/behavioral-8/8. Pre-shunt scans: frontal horn span 4.9±0.6 cm (range 4.2-6.2); ventricular asymmetry-2/8; IIIrd ventricle span 11.3±0.6 mm (range 8-15); corpus callosum effacement on MR-5/5; mild atrophy-4/8; no atrophy-4/8. Pre-shunt testing: tap test-2/8; ELD-3/8; none-3/8. Shunt response/complications: improved-3/8; unchanged/worse-5/8; subdural effusions-3/8; shunt removed and not replaced for low pressure symptoms-1/8. Neuropsychological testing-7/8, showing difficulty with encoding and retrieval, but not storage of information, suggesting more frontal than hippocampal/temporal dysfunction. Diagnoses: 1) FTD without NPH-4/8, including all 3 patients without gait impairment and 1 with mild gait impairment >20 years after colloid cyst surgery and shunt. 2) NPH and FTD-4/8, including 2 definite and 2 possible NPH who later developed FTD. DISCUSSION: FTD is associated with ventriculomegaly and (in some subtypes) impairment of motor and gait function that can be mistaken for NPH. Neither corpus callosum effacement nor absence of atrophy excludes FTD. Neuropsychological testing should be considered for 1) possible INPH patients with ventriculomegaly who lack gait impairment, and 2) shunted patients whose dementia worsens despite improved gait.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O27. DIFFUSION TENSOR IMAGING EXPOSES FURTHER LESIONS TO WHITE MATTER IN INPH Lenfeldt N. E.P. PhD MSc1,5, Larsson A. PhD2, Nyberg L. PhD2,3, Birgander R. MD PhD2, Eklund A. PhD2,4,5, Malm J. MD PhD1 (1) Department of Clinical Neuroscience, Umeå University, Sweden (2) Department of Radiation Sciences, Umeå University, Sweden (3) Department of Integrative Medical Biology, Umeå University, Sweden (4) Department of Biomedical Engineering and Informatics, Umeå University, Sweden (5) Centre for Biomedical Engineering and Physics, Umeå University, Sweden INTRODUCTION: This study applies diffusion tensor imaging (DTI) to assess fractional anisotropies (FA) and apparent diffusion coefficients (ADC) in brains of patients with INPH before and after withdrawal of CSF. MATERIALS AND METHODS: Eighteen INPH-patients and ten controls took part in the study. DTI was performed in a 1.5T MRI scanner before and after a three-day external lumbar drainage of approximately 400 ml CSF. Regions of interest (ROI) included genu, splenium and truncus of corpus callosum, anterior, genu and posterior capsula interna, frontal and lateral periventricular white matter, and centrum semiovale including areas related to SMA and pre- and postcentral gyri. FA and ADC were compared between patients and healthy, and between patients before and after drainage. The level of significance level was 0.05 corrected for multiple comparison. RESULTS: FA was decreased in INPH patients in three regions (p< 0.002, p< 0.001 and p< 0.0001) in frontal white matter, whereas elevated ADC was found in genu corpus callosum (p< 0.0001) and areas of centrum semiovale associated to the precentral gyri (p< 0.002). Diffusion patterns in these areas did not normalize after drainage. DISCUSSION: DTI reveals further injuries to frontal white matter – interpreted as axonal loss and gliosis –where high-order motor systems between cortical and subcortical structures travel, further supporting that motor symptoms in INPH are caused by a chronic ischemia to the neuronal systems involved in movement planning processes. O28. QUANTITATIVE EVALUATION OF CSF CIRCULATION AT THE AQUEDUCT OF SYLVIUS IN 3T MR UNIT Kapsalaki E.1, Tsougos I.2, Theodorou K.2, Paterakis K.N.3, Fountas K.N.3 (1) Department of Diagnostic Radiology, University Hospital of Larisa, School of Medicine, University of Thessaly, Larisa, Greece (2) Department of Medical Physics, University Hospital of Larisa, School of Medicine, University of Thessaly, Larisa, Greece (3) Department of Neurosurgery, University Hospital of Larisa, School of Medicine, University of Thessaly, Larisa, Greece INTRODUCTION:Accurate quantitative knowledge of cerebrospinal fluid (CSF) circulation through the aqueduct of Sylvius is of paramount importance for decision making in patients with hydrocephalus. Therefore, identification of normal variance of CSF dynamics in that area is essential for defining abnormal circulation patterns. The purpose of our current study was to evaluate the normal CSF flow measurements through the aqueduct in normal volunteers at 3T. MATERIALS AND METHODS: We prospectively performed cine MRI studies in 12 normal volunteers aged 17-42 years (mean 24.3). CSF flow measurements were performed on a 3T GE MR system (GE Medical Systems, Milwaukee, WI, USA). All studies were performed with a cardiac gated Gradient echo sequence at the upper, middle and lower part of the Sylvian aqueduct. Regions of interest (ROI) 52

Oral Presentations (O)

analysis was performed. RESULTS: CSF flow velocities were slightly increased at the upper part of the aqueduct than those obtained from the lower part of the aqueduct. However, these differences did not reach the levels of statistical significance. The mean peak positive velocity was measured 2.96(+/-0.62) cm/sec and the average flow was 0.053(+/-0.012) ml/beat. The obtained measurements had no significant difference compared with those obtained in lower field MR units. DISCUSSION: Normal data of CSF peak velocity and average flow through the cerebral aqueduct in young healthy volunteers were accumulated by using a high-field MR unit for defining normal range. Precise knowledge of normal CSF circulation is important for recognizing abnormal situations. O29. ENDOSCOPIC FOURTH VENTRICULOSTOMY ON TREATMENT OF FOURTH VENTRICLE OBSTRUCTIVE HYDROCEPHALUS Guo-qiang Chen, Qing Xiao, Jia-ping Zheng, Jin-ting Wu, Hui Liang, Huan-cong Zuo Department of Neurosurgery, Yuquan Hospital, Tsinghua University, Beijing, China INTRODUCTION: To summarize the indication, method and effect of endoscopic fourth ventriculostomy(EFV, means Magendie’s foramen fenestration) on treatment of fourth ventricle obstructive hydrocephalus. MATERIALS AND METHODS: 17 cases of fourth ventricle obstructive hydrocephalus treated by endoscopic fourth ventriculostomy with flexible neuron-endoscope from October, 2006 to December, 2009, were analyzed retrospectively. 12 male and 5 female patients whose ages ranged from 33 days to 48 years (mean 16.1 years). Isolated fourth ventricle due to postoperative intracranial infection in 5 cases and membranous obstruction of median (Magendie’s)or lateral(Luschka’s) foramen of fourth ventricle in 12 cases. Individual operation according to the endoscopic exploration was performed through a frontal precoronal burr hole with FUJINON EB-270P flexible neuroendoscope (diameter 3.8-mm, length 30-cm) and homologue appatatus. Single EFV in 7 cases, EFV with ETV(endoscopic third ventriculostomy) in 5 cases, EAP(endoscopic aquductoplasty) with ETV in 3 cases, EFV with EAP in 2 cases. The operative effect was evaluated by cine phase-contrast magnetic resonance imaging. RESULTS: 12 (70.6%) cases showed fine circulation of CSF in Magendie’s foramen. Of 5(29.4%) cases who showed no circulation of CSF in Magendie’s foramen by cine-MRI, 3(17.6%) cases had a fine circulation of CSF in the orificium fistulae of the third ventricle floor and need no other treatment, 2(11.8%) cases had to had ventriculoperitoneal (VP) shunt 1 week later because the intracranial hypertension could not be released. The symptom of all the patients disappeared with no complications related to operation appeared. DISCUSSION: Endoscopic fourth ventriculostomy(EFV) with flexible neuron-endoscope is a safe and effective method for the treatment of fourth ventricle obstructive hydrocephalus, regular CSF circulation can be put back in partial patients, but the operative indication should be obeyed strictly. KEYWORDS: Endoscopic fourth ventriculostomy (EFV), fourth ventricle obstructive hydrocephalus.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O30. A PROSPECTIVE, RANDOMISED, CONTROLLED TRIAL TO EVALUATE THE EFFICACY AND SAFETY OF ENDOSCOPIC CHOROID PLEXUS COAGULATION WITH THIRD VENTRICULOSTOMY IN THE TREATMENT OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (ISRCTN29863839) Edwards R.J., Aquilina K., Bunnage M., Pople I.K. Department of Neurosurgery, Frenchay Hospital, Bristol, UK INTRODUCTION: Previous retrospective studies have suggested that endoscopic treatment of NPH may be as effective as CSF shunting. We report a blinded PRCT comparing NPH patients treated with neuroendoscopy and patients treated with a programmable VP shunt. MATERIALS AND METHODS: Patients were randomised to neuorendoscopy (treatment) or VP shunting (control). Patients in the treatment arm were offered crossover to VP shunting in the event of treatment failure. The primary outcome measure (intention to treat analysis) was the 3-month Raftopoulos gait score assessed on gait video by a blinded assessor. Secondary outcome measures included modified Rankin Disablity Score; Barthel index; Dutch NPH score; Folstein MMSE Score and the Mattis II Dementia Rating Scale measured at 3 & 6 months and 2 years. The neuropsychologist was blinded to the treatment allocation. RESULTS: The trial was stopped early after randomisation of 21 patients due to concerns over a lack of efficacy. There were significant improvements in both gait (p=0.04) and mRS (p=0.001) at 3 months in the shunted group but not the neuroendoscopy group. Cognition, by a number of outcome measures, was significantly better in control patients at 3 & 6 months and 2 years. All patients in the neuroendoscopy arm eventually “crossed over” to CSF shunting. Comparison of preand post-crossover gait and functional scores showed a significant improvement after placement of a shunt, but cognitive scores did not improve. There were no stoma blockages. DISCUSSION: CSF shunting with a programmable valve is superior to treatment with endoscopic third ventriculostomy with choroid plexus coagulation in idiopathic NPH. O31. NORMAL PRESSURE HYDROCEPHALUS (NPH): INDICATIONS FOR ENDOSCOPIC THIRD VENTRICULOSTOMY (ETV) Paidakakos N., Borgarello S., Naddeo M. Department of Neurosurgery, C.T.O. Hospital, Turin, Italy INTRODUCTION: The goal of our study has been to analyze as thoroughly as possible the pathophysiological basis of NPH, so as to propose a diagnostic and prognostic routine able to correctly select NPH patients and to differentiate them in terms of surgical treatment, identifying probable ETV responders. MATERIALS AND METHODS: We have prospectively considered a group of 44 patients (21 male, 23 female; mean age 72.2, range 54-85) with suspected NPH on the basis of clinical symptoms and neuroradiological evidence (cerebral CT scan, MRI and cineMRI), that have undergone supplemental prognostic testing (Tap test, External Lumbar Drainage (ELD), CSF outflow resistance (Rout) determination through lumbar and ventricular infusion test). They have undergone either shunting or ETV or both. Follow up was 21.9 months on average (range 6-36). RESULTS: To choose the kind of treatment (shunt or ETV) we evaluated the individual response during infusion tests; a high ventricular Rout along with a normal lumbar Rout was the indication for ETV (cut-off value 15 mmHg/ml/min). The efficacy of both surgical techniques has been around 70%, with a significantly smaller complication rate in the case of ETV. DISCUSSION: We have evaluated the correlation between the various tests and the post operative outcome, both for shunting and for ETV. Rout has proven useful for preoperative assessment and 54

Oral Presentations (O)

choice of treatment. In carefully selected patients, ETV had similar qualitative results with shunting, presenting all the while an unimportant rate of complications. O32. COMPLICATIONS OF ENDOSCOPIC THIRD VENTRICULOSCOPY. A META-ANALYSIS Bouras T., Sgouros S. Department of Neurosurgery, “Attikon” University Hospital, University of Athens, Greece INTRODUCTION: Endoscopic third ventriculostomy (ETV) is an established treatment of hydrocephalus. Most studies focus on success rate; complications are insufficiently charted. The aim was to perform a meta-analysis of ETV complications. MATERIALS AND METHODS: A Medline search discovered 25 series of ETV (children 7, adults 5, mixed age 12), with detailed complications reports. RESULTS: The analysis included 2672 ETVs performed on 2617 patients. Cause of hydrocephalus was: aqueductal stenosis 25.9%, tumor 37.0%, meningomyelocele 6.1%, posthemorrhagic 5.8%, postinfectious 1.4%, cysts 3.3%, Chiari I 0.4%, Dandy-Walker malformation 0.3%, cerebellar infarct 0.9%, NPH 1.3%, not-recorded 16.8%. Overall complication rate was 8.8%. Permanent morbidity was 2.1%, neurologic in 1.2% (hemiparesis, gaze palsy, memory disorders, altered consciousness), hypothalamic in 0.9% (diabetes insipidus, weight gain, precocious puberty). Intraoperative hemorrhage was 3.9%, severe in 0.6% (including 4 cases -0.14% of basilar rupture). Other surgical complications were 1.13% (3 thalamic infarcts, 6 subdural, 6 intracerebral and 2 epidural hematomas). CSF infections occurred in 1.8%, CSF leak in 1.7%, anesthetic complications (bradycardia / hypotension) in 0.19% of cases. Postoperative mortality was 0.22% (6 patients; sepsis 2, hemorrhage 3, thalamic injury 1). Another 2 children suffered delayed “sudden death” (after 25 and 60 months respectively), caused by acute hydrocephalus due to stoma occlusion. There were no differences between pediatric - adult patients or short - long series (cutoff 100 patients). All deaths were reported in long series. Complications were insignificantly higher in short series. DISCUSSION: Permanent morbidity after ETV is 2.1%, mortality is 0.22%. The incidence of delayed “sudden death” is 0.07%. O33. THE ROLE OF ENDOSCOPIC THIRD VENTRICULOSTOMY IN THE TREATMENT OF SELECTED PATIENTS WITH NORMAL PRESSURE HYDROCEPHALUS Fountas K.N. MD PhD1, Kapsalaki E.Z. MD PhD2, Paterakis K.N. MD PhD1, Lee G.P. PhD3, Hadjigeorgiou G. MD PhD4 (1) Department of Neurosurgery, University Hospital of Larisa, University of Thessaly, School of Medicine, Larisa, Greece (2) Department of Diagnostic Radiology University Hospital of Larisa, University of Thessaly, School of Medicine, Larisa, Greece (3) Department of Neurology, Medical College of Georgia, Augusta, GA, USA (4) Department of Neurology, University Hospital of Larisa, University of Thessaly, School of Medicine, Larisa, Greece INTRODUCTION: The purpose of our study was to evaluate the results of endoscopic third ventriculostomy (ETV) in the management of patients with idiopathic normal pressure hydrocephalus (INPH). MATERIALS AND METHODS: Our prospective study included eight patients (5 males and 3 females; ages ranging between 31 and 78 years) with two or more typical NPH symptoms. Their preoperative work up included brain MRI and cine-MR, MMSE, and CSF lumbar drain test in all cases. 55

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 Additionally, head CT scan, radionuclide cisternogram, intracranial pressure monitoring, and visual field examination were selectively obtained. The clinical status of all participants was graded using the Japanese Intractable Hydrocephalus system. Our selection criteria for ETV candidates were: i) patient’s age less than 80 years, ii) duration of symptoms less than 6 months, iii) absence of any other clinically evident co-morbidity, iv) preoperative Mini-Mental Status Examination (MMSE) score ≥ 18, v) hyperdynamic cerebrospinal fluid flow in the aqueduct demonstrated on the preoperative cine-MR study (aqueductal CSF stroke volume >42 μL), vi) symptom improvement after lumbar CSF drain test, and vii) no previous shunt insertions. An ETV was performed in all participants. Follow up included periodic clinical evaluations, MMSE, and MRI with cine-MR studies. The follow up time range was 12-72months (mean: 36.7 m). RESULTS: The mean postoperative clinical grade was 2.7, while the preoperative was 6.4. Gait disturbance and urinary incontinence were the most responsive symptoms. The mean postoperative MMSE score was 24.3, while the preoperative one was 20. The mean postoperative aqueductal CSF stroke volume, six months after the procedure, was 30.8 μL, while the preoperative one was 49.7 μL. The calculated mean postoperative Evans’ ratio at the sixth postoperative month was 41.8%, while the preoperative one was 47.5%. DISCUSSION: ETV may be a safe alternative surgical option for a limited number of carefully selected INPH patients. O34. THE ROLE OF ARTIFICIAL CEREBROSPINAL FLUID AS PERFUSATE IN NEUROENDOSCOPIC SURGERY-BASIC INVESTIGATIONMasakazu Miyajima, Misuya Watanabe, Madoka Nakajima, Ikuko Ogino, Hajime Arai Department of Neurosurgery, Juntendo University, Tokyo, Japan INTRODUCTION: Neuroendoscopic surgery is most distinct from usual craniotomy in terms of the former being a procedure to be performed in water. We have previously reported that artificial CSF as perfusate in third ventriculostomy is more efficacious in minimizing severe host reaction than normal saline and lactated Ringer’s solution. In this study, we investigated the effects of different perfusion solutions in human cultured astrocytes. MATERIALS AND METHODS: We cultured human astrocytes in growth medium. Then each of them was further cultured for the period of six hours in artificial CSF, lactated Ringer’s solution or normal saline respectively. Using DNA microarray, RNAs were extracted from each of the cells and were comprehensively analyzed to find differences in patterns of gene manifestation. RESULTS: Compared with the use of artificial CSF, in cases where lactate Ringer’s solution or normal saline was used there was little difference in the pattern of gene manifestation while there was increase in gene manifestation related to apoptosis and inflammatory reaction. DISCUSSION: For neuroendoscopic surgery it is considered effective in maintaining brain homeostasis to use artificial CSF as perfusing solution in comparison with normal saline or lactate Ringer’s solution. O35. A TWELVE-YEAR HOSPITAL OUTCOME ON PATIENTS WITH IDIOPATHIC HYDROCEPHALUS Stranjalis G.1,2, Kalamatianos T.1,2, Koutsarnakis C.1,2, Loufardaki M.1,2, Stavrinou L.1,2, Sakas D.E.1,2 (1) Department of Neurosurgery, University of Athens, Athens, Greece (2) HCNR “Professor Petros S. Kokkalis”, Athens, Greece INTRODUCTION: This study aimed in determining the: (a) twelve-year variation rate, (b) age-gender characteristics, (c) shunt type, (d) postoperative shunt-related complications, and (e) hospital 56

Oral Presentations (O)

outcome, of patients with Idiopathic Hydrocephalus (IH) who underwent a first-ever shunt operation in our department. MATERIALS AND METHODS: An electronic database which included all patients that underwent shunt operations from 1998 to 2009 was used to retrieve retrospective demographic, clinical, and hospital outcome data. From this sample, identification of IH patients was based on classical clinical and imaging diagnostic criteria (Hakim’s triad, lack of secondary causes and ventriculomegaly). RESULTS: From a total of 734 patients who underwent 955 shunt operations/reoperations during the 12-year study period, 238 patients (32.4%) were identified with IH. The number of IH cases rose consecutively during the second (+129%) and the last (+91.5%) third of the study period. The mean age and male:female ratio of IH patients were 73.3 (± 7) years and 1.28:1, respectively. Ventriculoperitoneal shunts (n=129; 54.2%) were the most commonly used configurations, followed by ventriculoatrial (n=108; 45.4%) and lumbar-peritoneal (n=1; 0.4%). Intra-hospital postoperative shunt-related complications were hematomas (n=2; 0.84%), meningitis (n=1; 0.42%) and status epilepticus (n=1; 0.42%). A favourable outcome was reported for 66.8% of patients; 31.5% showed no change. Overall hospital mortality was 1.7% (4 postoperative deaths, 3 shunt-related). DISCUSSION: Our findings indicate a progressive rise in the incidence of IH; contributing factors are likely to include improved diagnosis and patient quality-of-life requirements. The immediate surgical results suggest relatively high improvement rates and infrequent postoperative complications. O36. INTRACRANIAL PRESSURE ANALYSIS IN PATIENTS WITH CHIARI 1 MALFORMATION Radek Frič, Per Kristian Eide Department of Neurosurgery, Rikshospitalet, Oslo University Hospital, Norway INTRODUCTION: The authors evaluate the significance of preoperative analysis of intracranial pressure (ICP) monitoring for decision making regarding treatment modality in patients with Chiari 1 malformation. MATERIALS AND METHODS: Data from 20 patients operated on for Chiari 1 malformation between June 2002 and June 2009 were evaluated; 5 children and 15 adults, a female predominance (15:5), median age 34.5 years (range 5-68 years). The patients underwent usual clinical and radiological workup. All 20 patients were investigated by continuous ICP-recording, with evaluation of intracranial compliance by analyzing the pulsatile component of ICP (mean wave amplitude, MWA). The median clinical follow-up was 26 months (range 9-101 months). RESULTS: 20 patients were investigated and 18 of them received a treatment. Based on ICP findings, four patients were primarily treated with ventriculo-peritoneal shunt only and eight with decompression of the foramen magnum. Six patients received subsequently both shunt and decompression, respectively, due to persistent symptomatology after the first procedure; shunt was inserted primarily in three of these patients, while decompression was the first choice in other three. DISCUSSION: Reduced intracranial compliance seems to be present in a significant proportion of patients with Chiari 1 malformation. We found ICP monitoring with analysis of the pulsatile pressure component to be an important tool in preoperative evaluation, particularly with regard to choice of surgical treatment modality. Primary treatment with ventriculo-peritoneal shunt should be considered in patients with significantly impaired intracranial compliance, independent of radiological evidence of hydrocephalus. We feel decompression of the foramen magnum to be safe as a primary treatment in patients with normal compliance, although minority of patients may still require a combined treatment with both decompression and shunting.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O37. A 22-YEAR-SERIES OF 1042 PATIENTS WITH 1271 ADJUSTABLE VALVES Dictus C., Biedermann N., Piotrowicz A., Unterberg A., Vienenkoetter B., Schiebel P., Hertle D., Haux D., Jung C., Aschoff A. Department of Neurosurgery, University of Heidelberg, Germany INTRODUCTION: The first adjustable valves (AV) were introduced by Bush & Matson in Boston in the early fifties and by Kuffer in Bern in 1969. In 1973 Portnoy & Schulte patented a palpatoric OnOff-valve and Hakim concepted the percutaneous adjustment using rotating magnets. In 1984 both adjustable Sophysa and Medos-Hakim-valves (Medos-P) were patented and Sophy-implantations started. The serial Medos-P was clinically introduced in our hospital in 1990. Later on followed STRATA-, ProGAV- and ProSA-valves. Inspite of numerous papers high volume series with a longterm follow-up are still missing. MATERIALS AND METHODS: Since 1988 we prospectively registrated 1042 patients with 1271 AVs; 665 had Medos-P, 325 Miethke-ProGAV, 15 Heyer-Schulte-ON-OFF, 16 Sophy-SU3/8, 3 SophysaPolaris, 17 Miethke-ProSA and one a Medtronic STRATA. RESULTS: The follow-up ranges 1 day to 20 years. 189 Medos-P-valves (27%), 34 ProGAV- (10.4%), 10 Sophy- and 2 ProSA-valves required at least one substitution, mainly due to adjustment-troubles (especially Medos-P, 7.9%), occlusions or infections. In vitro tests 100% of all testable AVs without gravitational devices showed overdrainage even in the highest adjustment when we simulated vertical positions, confirmed in vivo by ICP-measurements with unphysiological low ICPs in upright. Children with AVs alone developed a high quote of slit ventricles/± syndrom, microcephaly and aquired isolated forth ventricles (34), adults more subdurals. DISCUSSION: On one hand the optional “titration” of ICP is helpful, sometimes essentially for clinical success and handling mild overdrainage, on the other hand the lack of robustness, unsolved safety as well frequent adjustment and handling problems counterbalance the advantages. Published comparative clinical studies of conventional vs. AV-DP-valves showed similar results, while the combination AV + g-valve seems to be superior. However, improvements of robustness and handling are necessary in all existing AV-products. KEYWORDS: Hydrocephalus, Shunts, Adjustable valves, Valve failures. O38. THE IDIOPATHIC ADULT’S HYDROCEPHALUS. A HISTORICAL RESEARCH Missori P.1, Paolini S.2, Currà A.1 (1) Department of Neuroscience, Neurology and Neurosurgery, University of Rome “Sapienza”, Italy (2) University of Perugia, Neurosurgery, IRCCS “Neuromed” Pozzilli, Italy INTRODUCTION: Reports of idiopathic adult hydrocephalus prior to the 1965 description of idiopathic normal pressure hydrocephalus by Salomón Hakim and Raymond Adams are lacking in the literature. At that time, the literature available on this subject was very scarce; Hakim and Adams found only three papers dealing with symptoms associated with adult hydrocephalus, and in only one of McHugh’s cases did the symptoms and radiological studies fit with a diagnosis of INPH (Foltz et al., 1956; McHugh, 1964; Riddoch, 1936). MATERIALS AND METHODS: Through traditional or digital libraries and internet search engines, the historical sources dealing with idiopathic adult hydrocephalus were explored. The various hydrocephalus denominations appearing throughout the centuries in the different languages (hydrocephalus, dropsy in the head, dropsy of the brain, watery head, water in the head, hydrocephale, eaux dans le cerveau, wassersucht, wasserkopf, bol-hooft, idrocefalo, idropisia della testa, hydrocephalo, hidrocefalo) were considered. 58

Oral Presentations (O)

RESULTS: Early descriptions of the disorder were related to autopsy studies in the eighteenth and nineteenth centuries. The first observations of idiopathic adult’s hydrocephalus were related to the cadaver reports of Giambattista Morgagni. From the second half of the 1800s, idiopathic adult hydrocephalus appeared to have been forgotten in the medical literature. DISCUSSION: Many European physicians (anatomists, pathologists, pediatricians) have contributed to the discovery of the idiopathic adult’s hydrocephalus. Salomón Hakim and Raymond Adams conjoined the gait, urinary, cognitive impairment with the responsiveness of these patients to lumbar tap test and shunt surgery. O39. DYNAMICS OF CSF FLOW IN SLIT VENTRICLE SYNDROME Eymann R.1, Schmitt M.1, Antes S.1, Shamdeen M.G., Kiefer M. (1) Department of Neurosurgery, Medical School, Saarland University, Homburg-Saar, Germany (2) Department of Pediatrics, Medical School, Saarland University, Homburg-Saar, Germany INTRODUCTION: CSF flow dynamics in slit ventricles and slit ventricle syndrome are still under debate. MATERIALS AND METHODS: We used an ICP controlled automated computer controlled transport for external temporary CSF drainage via the new Möller-LiquoGuard® system in a child with known slit ventricle syndrome. External drainage was necessary due to intraperitoneal infection. The LiquoGuard allows presetting the drainage rate in ml/h and the ICP which had to be kept with a hysteresis of 1.5 mm Hg. If ICP increases over the preset value the LiquoGuard actively drains CSF with the preset volume-rate until the aimed ICP is reached. RESULTS: To achieve well tolerated values the ICP had to be set at 4 mm Hg. It was quite difficult to find initially an adequate drainage rate, since to keep the ICP at 4 mm Hg. Widely within time intervals of 2 hours varying drainage-rates between 0 – 35 ml/h were necessary. Choosing a too low presetting resulted in intolerable headache since ICP increased rapidly. If the drainage rate was set to high negative ICP and a loss of ICP-amplitude were measured in prone position indicating a ventricular collapse with EVD closed side-holes. The optimal drainage rate was about 25 – 30 ml/h since it avoided ICP-crisis as well as ventricular collapses. To maintain the desired ICP periods lasting 2 – 3 h could be identified during which the flow rate had to increase from 0 ml/h up to 30 ml/h steadily building a sawthoot CSF flow-pattern. DISCUSSION: Rapid CSF-flow alterations characterize the slit-ventricle-syndrome. O40. IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) IN A DEFINED POPULATION – LONG-TERM OUTCOME OF 172 SHUNTED PATIENTS Pyykkö O.T. BM1, Koivisto A. MD PhD3,4, Alafuzoff I. MD PhD3,5, Vainikka S. MD, Tamminen J. MD2, Tillgren T. MD2, Savolainen S. MD PhD2, Fraunberg M. MD PhD2, Pirttilä T. MD PhD3,4, Jääskeläinen J.E. MD PhD1,2, Soininen H. MD PhD3,4, Rinne J. MD PhD2, Leinonen V. MD PhD2 (1) Department of Neurosurgery, Kuopio University Hospital, Kuopio, Finland and University of Eastern Finland (2) Department of Neurosurgery, Kuopio University Hospital, Kuopio, Finland (3) Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland (4) Department of Neurology, Kuopio University Hospital, Kuopio, Finland (5) Unit of Pathology, Department of Clinical Medicine, University of Eastern Finland, Kuopio, Finland INTRODUCTION: Idiopathic NPH (iNPH) causes dementia that can be alleviated by shunting. Data on the incidence of iNPH as well as the long-term outcome and causes of death of shunted iNPH 59

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 patients in defined catchment populations are scarce. MATERIALS AND METHODS: Neurosurgery of Kuopio University Hospital solely serves a defined geographical area in Eastern Finland. Between 1993 and 2006, 368 patients were evaluated for a possible iNPH, including an ICP monitoring and a cortical biopsy. A total of 172 (47%) were shunted for iNPH, 71 males and 101 females at mean ages of 70 and 72 years. From 1993 to 2006, the catchment population decreased from 882 744 to 853 686. All 172 patients were followed up until death or the end of 2008, with a median follow up time of 4.7 years. The causes of death were obtained from the Statistics of Finland and hospital records. Logistic regression analysis with Cox models was applied. RESULTS: The average incidence of shunted iNPH was 1.4 / 100 000 / year, with a slightly increasing tendency. Of the 172 iNPH patients, 138 (80%) improved after shunting. The most frequent causes of 71 deaths were cardiovascular disease (26%), stroke (19%) and dementia (11%). Clinical dementia until death was observed in 59% of the patients. DISCUSSION: Cognitive decline in spite of shunting in iNPH, evaluated by an ICP monitoring and a cortical biopsy, in the absence of known etiology such as SAH or brain trauma, indicates that iNPH is still a heterogeneous syndrome. New approaches to elucidate its pathogenesis and to define it clinically are required. O41. THE VALUE OF CEREBROSPINAL FLUID DYNAMICS (CSF) AND ITS CORRELATION WITH TAP TEST FOR THE PREOPERATIVE ASSESSMENT OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) PATIENTS Aygok G.A.1, Kayis C.2, Marmarou A.1, Young H.F.1 (1) Department of Neurosurgery, Medical College of Virginia, Commonwealth University, USA (2) Department of Electrical Engineering, Virginia Commonwealth University, Richmond, VA, USA INTRODUCTION: To identify the role of a spinal tap with lumbar infusion study of CSF in determining which patients would benefit with shunting. MATERIALS AND METHODS: 125 patients diagnosed with INPH according to recommended guidelines were studied prospectively from 2005 to 2008. All patients underwent a lumbar infusion study using bolus technique followed by a 30 cc CSF removal. Video assessment of gait was conducted before and 30 minutes after the tap. A shunt procedure was then recommended to patients whose gait improved 30 minutes or 72 hours after tap. Shunt outcome was assessed at 3 months and 1 year. RESULTS: Of the 125 patients, gait improved in 61 immediately after tap. The mean pressure and PVI equaled 11.8+/- 3.6 mm Hg and 21.8+/-7.8 ml respectively .4 patients had Ro less than 4 mmHg/ ml/min. 59 of the 61 patients were shunted and 55 (93 %) improved at follow-up. Of the 64 patients who had no improvement at 30 minutes, the mean pressure and PVI equaled 9.5+/- 3.5 mm Hg and 20.5+/-8.6 ml respectively. 33 patients had Ro less than 4 mmHg/ml/min. 24 patients improved within 72 hours, 22 of the 24 patients were shunted and only 13 (59 %) improved at follow-up. DISCUSSION: Improvement with shunt was significantly different between those patients improving at 30 minutes and 72 hours (p <0.001). The overall accuracy of the tap equaled 80 %. Moreover, patients with Ro greater than or equal to 4 mm Hg/ml/min are most likely to have a positive tap response.

Oral Presentations (O)

O42. CORRELATION BETWEEN TAP TEST RESULTS AND CSF AQUEDUCTAL STROKE VOLUME IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS ElSankari S.1,2, Fichten A.3, Gondry-Jouet C.4, Csoznyka M.5, Legars D.3, Deramond H.4, Balédent O.2 (1) Neurology Department, Amiens University Hospital, Amiens, France (2) Imaging and Biophysics Unit, Amiens University Hospital, Amiens, France (3) Neurosurgery Department, Amiens University Hospital, Amiens, France (4) Radiology Department, Amiens University Hospital, Amiens, France (5) Academic Neurosurgical Unit, Department of Clinical Neurosciences, University of Cambridge, Addenbroke’s Hospital, Cambridge, UK INTRODUCTION: In spite of guidelines, the diagnosis and management of idiopathic NPH remains unclear. The role of CSF aqueductal stroke volume (ASV) remains unspecified. OBJECTIVES: To compare tap test (TT) and ASV results in patients with clinically defined INPH. MATERIALS AND METHODS: Among 22 patients investigated with both TT and Phase Contrast (PC) MRI for suspected INPH, we identified 2 groups: 1) those with a positive TT (PTT), and 2) with a negative one (NTT), and we compared their ASV as measured by PC-MRI. ASV cut-off value was set at 70 μl/cardiac cycle (mean value + 2 standard deviations in aged matched healthy subjects). RESULTS: In the PTT group (n=10), the mean ASV was of 178± 67 μl. In the NTT group (n=12), the mean ASV was of 96 ± 93 μl (p < 0.05). Among the non-responders, 3 had a hyperdynamic ASV and an associated neurodegenerative disorder diagnosed (Parkinson, vascular or Alzheimer disease). One patient had diagnosis of INPH but was not shunted because of severe dementia. Two patients were finally diagnosed with INPH despite of their NTT, and were improved after ventriculo-peritoneal shunting. Sensitivity and specificity were respectively of 62 and 100%. DISCUSSION: In our population, non-invasive measurement of hyperdynamic ASV correlates with PTT, suggesting a good specificity of PC-MRI for selecting those patients who would benefit from shunting. On the contrary, ASV seems more sensitive than TT. We therefore suggest ASV as a supplemental diagnosis tool in NPH in order to improve sensitivity in selecting shunting indication. O43. TAP TEST - TIME WINDOW AND CONSISTENCY Virhammar J.1, Cesarini K.G.2, Laurell K.1 (1) Department of Neuroscience, Uppsala University Hospital, Sweden (2) Department Neurology and Neurosurgery, Uppsala University Hospital, Sweden INTRODUCTION: The CSF tap test (TT) is one of the diagnostic tools used to select patients with idiopathic normal pressure hydrocephalus (INPH) who may benefit form shunt surgery. The performance of TT and the evaluation time varies between centres. We aimed to identify the optimal time window for gait improvement after TT, to assess the variability between two measurements and the interrater agreement of the gait tests chosen. MATERIALS AND METHODS: Forty patients with clinical and neuroimaging signs suggestive of INPH underwent a TT. Evaluation included standardised gait analysis before and 2, 4, 6, 8 and 24 hours after the TT, and measurements of number of steps and speed for a fixed 10-meter distance. Measurements were repeated and the first walk on every occasion was video recorded. Improvement was defined as 10 % reduction of time and number of steps or 20% reduction in one of each. DISCUSSION: Twenty-seven patients improved after TT. Improvement in both speed and number of steps was significant on every occasion post TT. Interrater agreement of gait assessment was high with a κ value of 0.74.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 In this sample of patients the reliability of the TT was good, with an ICC=0.97 for number of steps as well as for speed. DISCUSSION: Our results suggest that the TT can be evaluated at any time within the first 24 hours. Gait analysis appears reliable regardless of the evaluator. We will also discuss how post lumbar puncture pain can affect the performance. O44. NEUROPSYCHOLOGICAL CHANGES FOLLOWING SHUNT TREATMENT IN THE EUROPEAN MULTICENTRE STUDY ON INPH Hellström P., Klinge P., Tans J., Wikkelsø C. Institute of Neuroscience and Physiology, Göteborg University, Sweden INTRODUCTION: Neuropsychological dysfunction is common in patients with idiopathic normal pressure hydrocephalus (iNPH). The deficits have been shown to be highly interrelated and associated with other signs that characterize the disorder, e.g., the gait, balance and incontinence problems (ref ). The severity of the neuropsychological deficits varies considerably among patients for reasons that are unknown. Shunt treatment is beneficial, some patients reaching complete or almost complete recovery, while others show only minor improvement. The factors behind this heterogeneity are also largely unknown. We aim to describe preoperative neuropsychological findings and changes following three and twelve months of shunt treatment, and to explore the influence of different factors on the pre- and postoperative performance of patients in the European Multi-centre study on iNPH. We will also discuss the need for a common standard for the classification of neuropsychological changes and measurement of their magnitude and present suggestions to such a standard. MATERIALS AND METHODS: One hundred and forty-two iNPH patients were tested with the ReyAuditory Verbal Learning Test (RAVLT), the Grooved pegboard and the Stroop test before and after three and twelve months of treatment. Their performance was compared to that of 108 healthy individuals (HI). RESULTS: Like in previous studies on the neuropsychology of iNPH, the performance of patients was significantly reduced in comparison to HI before surgery. Results were significantly improved after three months of treatment and remained stable until the one year follow up. Despite improvement, patients still performed well below HI. Risk factors for cerebrovascular disease contributed significantly to the severity of neuropsychological deficits before and after treatment, whereas neither ventricular size nor variables derived from csf dynamic tests were associated with neuropsychological test results. DISCUSSION: The neuropsychological impairment of patients with iNPH responds to treatment but performance levels stay below those of HI. Neither ventricular size nor csf dynamics were helpful in the prediction of neuropsychological functions. The need for agreement concerning test choice, and more importantly, regarding methods for classification and measurement of clinically significant neuropsychological changes will be emphasized.

Oral Presentations (O)

O45. CHARACTERIZATION OF URINARY INCONTINENCE IN PATIENTS WITH NORMAL PRESSURE HYDROCEPHALUS (NPH) Klausner A.P.2, Aygok G.A.1, Young H.F.1, Boling P.A.3, Wolfe L.2, Koo H.P.2, Marmarou A.1 (1) Department of Neurosurgery, Medical College of Virginia Commonwealth University, Richmond, VA, USA (2) Department of Urology, Medical College of Virginia Commonwealth University, Richmond, VA, USA (3) Department Internal Medicine, Medical College of Virginia Commonwealth University, Richmond, VA, USA INTRODUCTION: The purpose of this investigation was to characterize the type, severity, and quality-of-life impact of urinary incontinence in patients with NPH. MATERIALS AND METHODS: NPH patients were administered validated surveys from the International Consultation on Incontinence modular questionnaire to assess incontinence, overactive bladder, quality-of-life impact from lower urinary tract symptoms (LUTS), and the AUA symptom index bother score. Patients with moderate to severe LUTS were offered urodynamics. RESULTS: Ninety-eight patients with NPH completed all 4 surveys. For unshunted patients (N=55), the incontinence survey revealed about once/day leakage with small to moderate leakage volumes. The overactive bladder survey demonstrated that the most severe symptom was “nocturia.” Quality of life impact related to LUTS was moderate for both surveys. For 18 patients whose survey data available both pre- and post-shunting, total incontinence scores decreased (8.4 ± 1.2  5.6 ± 0.93, p<0.05) as did scores for leakage volume (2.8 ± 0.4  2.0 ± 0.3, p<0.05). The “frequency” score for the overactive bladder survey decreased (1.1 ± 0.2  0.2 ± 0.1, p<0.05), and the quality of life score (AUASS) decreased (3.2 ± 0.3  2.1 ± 0.4, p<0.05). Urodynamics revealed detrusor overactivity in 24/28 (88.9%) patients, reduced bladder capacities (223.6 ± 23.4ml), elevated peak pressures (85.4 ± 8.8 cm H20) and small residual urine volumes (70.9 ± 20.6 ml). DISCUSSION: This is the first study to establish the type, severity, and quality-of-life impact of LUTS related to NPH using validated surveys and urodynamics. Further research may identify factors that predict favorable responses to shunting. O46. PROPOSAL AND EVALUATION OF A COMPUTERISED NEUROPSYCHOLOGICAL TEST BATTERY FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) Behrens A.1, Eklund A.2,3,4, Elgh E.5, J. Malm1 (1) Department of Clinical Neuroscience, Umeå University, Sweden (2) Department of Biomedical Engineering and Informatics, Umeå University, Sweden (3) Centre for Biomedical Engineering and Physics, Umeå University, Sweden (4) Department of Radiation Sciences, Umeå University, Sweden (5) Department of Community Medicine and Rehabilitation, Umeå University, Sweden INTRODUCTION: A novel computerised neuropsychological test battery for INPH has been developed to provide the clinician with a standardised tool assessing the cognitive domains specific for INPH. The aim of this study was to investigate the reliability, validity and feasibility of the battery. MATERIALS AND METHODS: The tests are presented on a touch-screen monitor connected to a standard computer. Each test is presented by an animation with concurrent speaker sound. The tests were selected from the literature on INPH. The battery takes about 30 minutes to complete. The validity was tested using the following patient cohorts:Test-retest reliability, 44 healthy elderly

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 (62-80 years); Validity (against similar paper and pencil tests), 32 patients with various neurological diagnoses (30-80 years and MMSE 22-30); Feasibility, seven possible INPH before and after a CSF tap test. RESULTS: Test-retest reliability and validity for the different tests (r_xx, r_xy): 2-Choice reaction test (0,60, -), Trail making test A (0,83, 0,87), Trail making test B (0,79, 0,84), 10-Word List (0,63, 0,67), Delayed Recall (0,50, 0,75), Recognition (0,70, 0,36), 4-finger tapping (0,90, -), Stroop color (0,60, 0,88), Stroop test (0,87, 0,71), Copy task (0,47, 0,56). All seven INPH patients managed the test. DISCUSSION: The test battery is the first computer test customised for INPH. Most tests showed good reliability and validity. The battery has potential as a valuable tool for the clinician and in INPH research. O47. ASSESSING TRIAL DESIGN CHOICES IN A DEVICE-BASED AD EFFICACY STUDY: A POST HOC ANALYSIS OF CHRONIC CSF DRAINAGE Silverberg G. MD1, Saul T.1, Williams J. MD2 (1) Warren Alpert Medical School, Brown University, Providence RI, USA (2) Oxford University, Oxford, UK INTRODUCTION: We conducted the first device-based efficacy trial in AD: chronic low flow CSF drainage. Trial design proved problematic. Subject selection, primary end-point sensitivity and statistical modeling adversely impacted outcome. MATERIALS AND METHODS: Post hoc analysis of study data was carried out following closure of the trial. Subject enrollment was analyzed by comparing the Mattis Dementia Rating Scale (MDRS) subject stratification to the screening Mini-mental Status exam (MMSE). Primary end-point selections, MDRS and Global Deterioration Scale (GDS), were analyzed by comparing the primary end-point sensitivity to prospectively collected secondary end-point data. The statistical model chosen was compared to other models using the same outcome data. RESULTS: Study failure was attributable to three design choices: i) screening MMSE: the study enrolled >30% moderate to severe AD patients despite MMSE entry criteria selected to enroll only mild to moderate subjects; ii) the second primary end point: the GDS was not sensitive to change over the nine months double-blind portion of the study. The AD Cooperative Study-Activities of Daily Living Inventory (ADCS-ADL – a secondary end-point) showed benefit to the treatment group (p<0.05); iii) the generalized estimating equation (GEE) could not manage the wide variances in outcome data as did mixed effects models. Using the MDRS and ADCS-ADL as end-points, both subset analysis (MDRS≥100) and the entire data set (n=181) showed benefit to the treatment group using a mixed effects model (p<0.05). DISCUSSION: Increasing CSF turnover and clearance may be of benefit in AD. Post hoc analysis shows that design choices in this clinical trial adversely biased the outcome. O48. THE VALIDITY OF JAPANESE INPH GUIDELINES IN A PROSPECTIVE STUDY OF INPH (SINPHONI) Hashimoto M.1, Ishikawa M.2, Mori E.3, Kuwana N.4 (1) Noto General Hospital, Japan (2) Rakuwakai Otowa Hospital, Japan (3) Touhoku University Graduate School of Medicine, Japan (4) Tokyo Kyosai Hospital, Japan INTRODUCTION: SINPHONI (study of idiopathic normal pressure hydrocephalus on neurological 64

Oral Presentations (O)

improvement) is a 26 multicenter prospective 1-year cohort study performed in Japan to validate the efficacy and safety of MRI-based diagnosis and the ventriculoperitoneal (VP) shunt with CodmanHakim programmable valve (CHPV) for iNPH. In this report, we present the validity of Japanease iNPH guidelines (JINPHGL) from the results of SINPHONI. MATERIALS AND METHODS: The favorable outcome (FO) was defined more than one point on modified Rankin scale (mRS) at one year after surgery. The result of full set 100 cases (averaged age:75 years) analysis was interpretated according to the JINPHGL . RESULTS: The FO was achieved in 69%, and 80% of shunt responder (SR) during one year. In tap responder group (89 cases), shunt responder was observed 77 (82%) in mRS and 83 (93%) in iNPHGS. On the other hand, in tap non-responder group (11 cases), 7 cases (64%) shows SR. In one year follow up period, 11 (7) cases showed temporary shunt effects in mRS (INPHGS). Serious adverse events were recorded in 15 patients including three events related to the VP shunt. Subdural effusion and orthostatic headache were reported as non-serious shunt-related adverse events, which were well controlled with readjustment of valve pressure. DISCUSSION: High-convexity tightness and dilated sylvian fissure on MRI is a valuable sign of shuntresponsive iNPH, and VP shunt with CHPV is safe and effective for patients with iNPH. And then, the validity of JINPHGL in the clinical scene is reconfirmed from SINPHONI results. O49. ATRIAL SHUNTS – NEUROSURGICAL ATAVISM OR ESSENTIAL SECOND-CHOICE PROCEDURE? Aschoff A., Sakowitz O., Dictus C., Haux D., Steiner-Milz H. Department of Neurosurgery, University of Heidelberg, Germany INTRODUCTION: The VA-shunt was common until the 70ties. Due to growth problems in children, the difficult placement and complications the use decreased. More recently Cochrane reported 2.3%, Patwardan 0.5% VA-shunts in children. The number of “trained” VA-surgeons (<20 procedures) or “experts” (>100) decreases, in some hospitals to zero. MATERIALS AND METHODS: We reevaluated 290 atrial shunts since 1987. RESULTS: We had no perioperative death due to atrial catheter, 1 cor pulmonale (0.34%), 2 emboli into A. pulmonalis requiring cardiosurgery (0.7%; external cases) and 1 pericard-tamponade. 4 own and 3 external patients developed a shunt-nephritis (1.4%; together 2.4%; most historical cases). 15 had a sepsis (5.2%), 2 an endocarditis (0.7%). The vital atrial complications were rare; retrospectively they developed over months. With regular cardiologic checks an early diagnosis should be possible. Wandering of 5 catheters (1.7%) into the A. pulmonalis had no cardiopulmonal impact; in all a simple endovascular extraction was possible. The retraction by growth in children was the most frequent problem. Intravenous catheter loops (5) counted 1.7%). – Actual statements (Bayston 07, Bergsneider 07) confirm, that VA-shunts have a fair risk not far from VP-shunts. DISCUSSION: The horror-image of VA-shunts differs from the reality. VA-shunts remain necessary in about 2-3% of children and 5-7% of adults. Every hospital should train at least 2-4 surgeons in this procedure. New techniques such as Seldinger-catheterization and placement control with intracardial ECG are fast and simple. However, a lifelong check one times per year and and information of the inherent risks to all involved doctors are obligatory.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O50. DIVERSE MORPHOLOGY IN ARACHNOID CYSTS INDICATES DIFFERENT EMBRYOLOGICAL ORIGIN Rabie K.MD3, Tisell M. MD PhD2, Högfeldt M. MD2, Wikkelsø C. MD PhD3, Johansson BR. MD PhD1 (1) Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Sweden (2) Department of Neurosurgery, Sahlgrenska Academy, University of Gothenburg, Sweden (3) Department of Neuroscience, Sahlgrenska Academy, University of Gothenburg, Sweden INTRODUCTION: Arachnoid cysts (AC) are fluid containing cyst-like malformations of arachnoid tissue and are found throughout cranial-spinal axis. Some expand over time. Suggested mechanisms for expansion include the one way valve theory, fluid secretion by cells lining the cyst lumen and osmosis. MATERIALS AND METHODS: 17 consecutive patients (10 m, 7 f ) with symptomatic AC were included. Mean age was 37 years (13-73). 10 cysts were located in temporal fossa, 5 in posterior fossa and 2 overlaying frontal cortex. Patients were examined by clinical examination, MRI and radionuclide cisternography (RC) previous to surgery. Surgical samples were divided in two parts; one part was sent for routine neuropathological diagnosis and one part examined by transmission electron microscopy (TEM). Clinical parameters were analysed. RESULTS: All patients improved after fenestration. All cases were diagnosed as AC in pathological exam. At TEM AC membranes were heterogeneous and based on the morphology, the cysts were divided into three different groups. Group A (8) has similar structure to normal arachnoid matter. Group B (3) consisted of thick connective tissue layer. Group C (6) had a differentiated epithelium with 1-3 cell layers lining the cyst lumen. The onset of symptoms was related to cyst morphology. DISCUSSION: The diverse morphology of the cysts indicates different embryological origin of cysts classified as arachnoid cysts. Early embryological perturbations play an important role in cystogenesis. Head trauma might contribute to cyst expansion and debut of symptoms in a subgroup of AC with specific morphology. The morphology might be important for reoccurrence of several years after surgery. O51. CONSERVATIVE VERSUS SURGICAL TREATMENT OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Toma A., Papadopoulos M., Stapleton S., Kitchen N., Watkins L. INTRODUCTION: Idiopathic normal pressure hydrocephalus (INPH) is an adult-onset syndrome where non-obstructive enlargement of the cerebral ventricles occurs concomitantly with one or more of the symptoms of gait disturbance, cognitive impairment and urinary dysfunction, in the absence of raised intracranial pressure. First described in 1965, etiology and pathogenesis remain unclear. Surgical diversion of CSF with a shunt system is the standard treatment for INPH based on class II evidence. Many surgeons, neurologists and radiologists do not believe it exists as a separate condition. MATERIALS AND METHODS: A prospective randomized blinded study has been started in July 2008 at the National Hospital for Neurology and Neurosurgery comparing the surgical and (conservative) treatment of INPH. Patients with probable INPH according to the international guidelines are randomly assigned into two groups: group A have the adjustable shunt valve immediately adjusted to function and group B will have the shunt adjusted on highest setting for 3 months then adjusted to function. The primary endpoint is an improvement in gait while the secondary endpoints are improvement in mental function, improvement in urinary function and incidence of complications. RESULTS: We are presenting the current results from the first few patients recruited in this study 66

Oral Presentations (O)

without uncovering the randomization of the 2 groups of patients. DISCUSSION: This study could provide class I evidence supporting or refuting the role of surgical management in INPH. O52. AMPLITUDES OF ICP PULSATIONS IN A WIDE PRESSURE RANGE Qvarlander S. MSc1, Malm J. MD PhD2, Eklund A. PhD1,3 (1) Department of Radiation Sciences, Umeå University, Sweden (2) Department of Clinical Neuroscience, Umeå University, Sweden (3) Department of Biomedical Engineering, Umeå University Hospital, Sweden INTRODUCTION: Recent research on Idiopathic Normal Pressure Hydrocephalus (INPH) suggests that the cardiac related pulsations in the intracranial pressure may predict the outcome of shunt surgery. In order to better understand the effect of a CSF shunt on the cardiac pulsations, we aim to model the relationship of pressure and pulsations in a wide pressure range, including pressures below the preoperative resting level, where the postoperative resting pressure is likely to be. MATERIALS AND METHODS: Twenty-five preoperative patients with possible INPH underwent a lumbar constant pressure infusion investigation. Pressure evaluation started at the peak, after infusion of Ringer solution, and continued during spontaneous return to resting pressure, as well as during drainage. This provided samples in a wide range, from 30 mmHg down to zero. Mean pressure and pulsation amplitude were determined for consecutive 1.5 second intervals. Data from each patient were normalized and group averages determined. The pressure was plotted versus the amplitude. RESULTS: Two distinct phases were found (see figure): a linear phase was observed for higher pressures, similar to what has been previously described[1]. In the second phase, at low pressures, the pulsations reach a minimum and then remain essentially constant. Resting pressure values of individual patients could be found in either phase. DISCUSSION: Potentially the model could be used preoperatively to identify patients with a possibility for pulsation reduction, and postoperatively to aid in the setting of adjustable CSF shunts by predicting a pressure which should minimize the pulsations and hopefully improve clinical outcome.

Figure. The relationship between pulsation amplitude and ICP exhibited a constant and a linear phase. 67

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 O53. SYMPTOMS AND SIGNS IN 158 PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Tullberg M. MD PhD, Skagervik I. MD, Edsbagge M. MD, Hellström P. MSc, Blomsterwall E. RPt MSca, Wikkelso C. MD PhD Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden INTRODUCTION: The description of the essential symptoms and signs in patients with idiopathic Normal Pressure Hydrocephalus (iNPH) still needs to be elucidated for diagnostic and predictive reasons. MATERIALS AND METHODS: We prospectively registered symptoms and signs, demographic data and co-morbidity in patients with iNPH later operated upon by shunt surgery. In order to identify features not earlier recognised we performed a semi-quantitative neurological examination. 158 consecutive patients diagnosed with iNPH during 1978 to 2005 were included. All patients were clinically evaluated according to a standardized protocol. RESULTS: The patients were aged 69 ± 10 years (mean ± SD). Besides gait disturbance, cognitive impairment and bladder symptoms, the patients presented with paratonia of the lower extremities (72 %), increased need of sleep (63 %), pathological Romberg’s test (62 %), retropulsion (49 %), focal neurological signs (37 %), polyneuropathy (31 %) and cerebellar signs (21 %). The frequency of hypertension was 34%, diabetes 17% and 16 % had other vascular co-morbidity. DISCUSSION: Frequent clinical features in iNPH, besides gait, cognitive and bladder disturbance, are paratonia, postural dysfunction, increased need of sleep and focal neurological and cerebellar signs. Neither the presenting symptom at onset of the disorder nor the dominating symptom seems to reflect the phenotype of the individual patient. O54. TEN YEARS OF EXPERIENCE WITH THE USE OF PROGRAMMABLE AND FIXED PRESSURE VALVES. A RETROSPECTIVE COMPARATIVE STUDY OF 159 PATIENTS Gatos H., Mpakopoulou M., Paterakis K., Fountas K. Department of Neurosurgery, University Hospital of Larisa, School of Medicine, University of Thessaly, Larisa, Greece INTRODUCTION: The purpose of our current study is to present our 10 year-experience from the use of either programmable or fixed-pressure valves and compare them in patients requiring CSF diversion. MATERIALS AND METHODS: In a retrospective study we reviewed 159 patients (89 male and 70 female) suffering from hydrocephalus of various etiology: 36 of post hemorrhagic origin (23%),19 of post traumatic etiology (16%),45 due to an associated space occupying lesions (28%), 49 from NPH (30%) and 3 from pseudotumor cerebri. The valves initially implanted were 40 fixed pressure and 119 programmable. Ventriculo-atrial shunt was implanted in 3 cases, lumbo-peritoneal in 5, while in all other cases a ventriculo-peritoneal shunt was inserted. RESULTS: The observed cumulative revision rate was 40% in patients with fixed-pressure valves. In 20% of these patients, a revision due to valve mechanism malfunction was undertaken and the initially-implanted valve was replaced with a programmable one. Revision of the ventricular or peritoneal catheter was performed in another 20%. Contrariwise, the respective cumulative revision rate for the programmable-valve group was 20%. The observed infection rate for the fixed-pressure group was 3%, while for the programmable valve was 0%. Subdural fluid collection was noticed in 17% of the fixed-pressure cases, while the respective rate for the programmable valve was only 4%. 68

Oral Presentations (O)

DISCUSSION: Analysis of our data shows that the revision and the overdrainage rates were significantly lower with programmable valves compared with fixed-pressure valves. O55. A 25-YEAR-SERIES OF 700 PATIENTS WITH GRAVITATIONAL VALVES Vienenkoetter B., Haux D., Jung C.S., Unterberg A., Dictus C., Aschoff A. Department of Neurosurgery, University of Heidelberg, Germany INTRODUCTION: The first gravitational (g)-valve (Hakim-Lumbar, 1975) was designed for lumbar shunts. After winning excellent results (Richard and our team) testing this valve, we were the first institution to propose the combination of g- with adjustable valves in 1991. MATERIALS AND METHODS: In 700 patients since1984 we implanted 968 g-valves: 11 HakimLumbar, 64 GCA (Cordis), 597 ShuntAssistant, 14 Dual-Switch, 17 adjustable ProSA, 38 GAV and 228 PaediGAV (Miethke). In-vitro we studied 141 gravitational valves (10 different designs). RESULTS: In horizontal valve position the g-valves show identical hydraulic properties like ballvalves with comparable pressures. In vertical position the flow was dramatically reduced. In our experience the selection of the pressure range, relative to hight and BMI of the patients, as well as the exact vertical implantation proved to be surprisingly difficult, especially in children, head and lumbar implantations. Every second g-valve-revision was caused by suboptimal pressure selection, which is potentially solved by adjustable ProSA. The overdrainage was markedly reduced: only 2.5% of the patients required surgery due to spontaneous subdural hematomas. After using g-valves we had no single case of trapped 4th ventricle (before 34), no hyperostatic bone and no acquired Chiari in lumbar shunting. - The rate of infections, catheter problems and valve dysfunctions matched literature values. DISCUSSION: Gravitational valves have largely solved the problems of overdrainage. Residual problems such as adaptation to children´s growth or high abdominal counterpressure in adipous patients require adjustable g-valves. A vertical position must be tightly adhered to. O56. SUBDURAL OR INTRAPARENCHYMAL PLACEMENT OF LONG-TERM TELEMETRIC ICP MEASUREMENT DEVICES? Schmitt M., Eymann R., Antes S., Kiefer M. Department of Neurosurgery, Medical School, Saarland University, Homburg-Saar, Germany INTRODUCTION: It is under discussion whether subdural placement can avoid cerebral violations in telemetric ICP measurement and accordingly we compared suitability of subdural and intraparenchymal placement. MATERIALS AND METHODS: A subdural and an intraparenchymal Raumedic’s telemetric ICPmeasurement-device (Rautel) were implanted in 9 minipigs. To validate the telemetric data each 3 months conventional ICP measurement was performed. If given, histopathology had to fix the failure reason. RESULTS: In one animal such precondition were given 12 months after Rautel implantation. Already computertomography revealed why the intraparenchymal device provided no reliable data: Despite implantation was performed in adult animals the scull dimensions still increased and the sensor tip has been located on the level of the tabula interna explaining easily mismeasurement. Much more important was the finding at gross inspection of the subdural catheter. The chronic pulsatile stress on the device resulted in a kind of a chamfer comparable with those of meningeal arteries. Some parts of this chamfer even were covered by a thin bony layer encapsulating the catheter to some extent. Since the measuring sensor surface at its tip pointed outward and not to the brain it is also 69

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 obvious why it had to fail. Gross inspection of the parenchymal track of the parenchymal device which provided reliable data for 9 months revealed no serious damages. DISCUSSION: Since in the remaining animals only 50% of the subdural but all intraparenchymal catheters provide reliable data after 12 months we favour intraparenchymal placement that similar encapsulation of the subdural devices may account for that. O57. VENTRICULOATRIAL (VA) SHUNT CAN IMPROVE SAFELY HIGHER CORTICAL FUNCTION IN THE PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) Kiyoshi Takagi1,2, Katsuhiko Takeda3 (1) Department of Neurosurgery, Chiba-Kashiwa Tanaka Hospital, Japan (2) Department of Neurosurgery, Fujita Health University, Japan (3) Department of Neurology, Mita Hospital, International University of Health and Welfare, Japan INTRODUCTION: Ventriculoperitoneal (VP) shunt is most frequently aplied and ventriculoatrial (VA) shunt is almost abandoned in order to treat idiopathic normal pressure hydrocephalus (iNPH). However, VA shunt has many advantages such as; (1) narrow operative field that can reduce infection rate, (2) no influence of obesity, (3) no influence of intra-abdominal high pressure that may be a cause of shunt dysfunction, (4) low intra-atrial pressure may guarantee constant flow, and (5) low flow resistance because of short catheter length. The purpose of this study is to investigate whether VA shunt improve higher cortical function by comparing the total score of frontal assessment battery (FAB) before and after VA ahunt. MATERIALS AND METHODS: VA shunt was performed in 18 cases with probable iNPH. Total score of FAB was assessed before and 3 months after the shunt. Paired t-test was applied for the statistic analysis. Data are shown in mean +/- SD. RESULTS: Mean age was 78.3 +/- 4.7 years old (male: female = 11: 7). Mean duration from onset to VA shunt was 22.2 +/- 17.7 months. Mean operation time was 41.4 +/- 12.7 minutes. Mean FAB were 11.6 +/- 3.7 before surgery and 12.9 +/- 3.4 3 months after the shunt (p = 0.0236). We observed no infection and no deterioration. DISCUSSION: This study indicates that VA shunt can safely improve higher frontal cortical function in iNPH patients. O58. VIRCHOW-ROBIN SPACES IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS: A SURROGATE IMAGING MARKER FOR MICROVASCULAR DISEASE? Tarnaris A., Tamangani J., Fayeye O., Murphy H., Kombogiorgas D., Gan Y.C., Flint G. INTRODUCTION: Virchow-Robin spaces (VRS) are perivascular spaces that surround the perforating arteries that enter the brain. With advancing age, VR spaces are found with increasing frequency and larger apparent sizes. Some studies have found an association with diseases associated with microvascular abnormalities. The aim of the study was to examine the incidence of VRS in patients with iNPH and consider its use as a surrogate imaging marker of microvascular disease. MATERIALS AND METHODS: The MR features of 12 patients with “probable” iNPH and incidence of VRS in the centrum semiovale (CS), basal ganglia (BG), mesencephalon (ME) and the subinsular region (SI) were reviewed. The VRS scoring system as proposed by Patankar et al. was used to compare the scores obtained with historical controls (n=35) from that study, and a control group (n=11) having imaging for screening of neurological conditions. RESULTS: No correlation between age and the incidence of VRS was noted. All 12 iNPH patients had 70

Oral Presentations (O)

visible VRS in the CS, 9 out of 12 had evidence in the SI region, and 6 out of 12 in the ME region. The scores obtained for the iNPH group were: 2.25 for BG, 1.66 for the CS, 0,91 for the SI region and 0,5 for the ME region. The respective scores for the historical controls and our control group were 1.46, 0.51, 0.96, 0.51 and 1.81, 1.54, 0.9 and 0.18. There were no significant differences in the frequency of VRS between the 2 studied groups. DISCUSSION: Our study provided initial of evidence of a higher incidence of VRS in iNPH when compared to a control population. A larger study to evaluate its clinical use as a surrogate marker of of microvascular disease in iNPH is warranted. O59. BRAIN CT SCAN INDEXES IN THE NORMAL PRESSURE HYDROCEPHALUS: PREDICTIVE VALUE IN THE OUTCOME OF PATIENTS AND CORRELATION TO THE CLINICAL SYMPTOMS Stamatiou S., Chatzidakis E., Fratzoglu M., Barkas K., Markellos A., Voidonikolas L., Kyriakou T. Department of Neurosurgery, General State Hospital of Nikaia, Piraeus, Saint Panteleimon, Greece INTRODUCTION: We looked for any predictive value in the estimation of brain CT scan indexes in patients with normal pressure hydrocephalus (NPH), in whom a shunt is going to be placed. MATERIALS AND METHODS: It is well known that it is very difficult to decide who is going to improve after shunting. We studied 40 cases of patients with the diagnosis “NPH” in whom the ventricular shunts were placed. Every symptom (motor disturbance, deficit of memory, incontinence) was separately evaluated preoperatively. The outcome of shunting was also evaluated and the patients were graded. The following CT scan indexes were estimated from the preoperative CT scans of the brain in every case: the ventricle-brain ratio (VBR), the bi-caudate and bi-frontal ratios, the third ventricle-Sylvian fissure (3V-SF) ratio, and the four largest cortical gyri. The method we have used for statistics is “one way analysis of variance”, correlating the CT scan indexes to the symptoms of the patients preoperatively, and the outcome of them postoperatively. RESULTS: We found correlation of the CT scan indexes of the brain in patients with NPH with the clinical symptoms but no correlation among them and the outcome after shunting procedures. DISCUSSION: The main conclusion is that the size of the lateral ventricles of the brain preoperatively is not correlated to the outcome after CSF shunting surgery, but it is correlated to the symptoms of NPH preoperatively. O60. PROSAIKA - PROGRAMMABLE SHUNTASSISTANT IN INITIAL CLINICAL APPLICATION. DESIGN OF A PROSPECTIVE MULTICENTER STUDY Kehler U.1, Kiefer M.2 (1) Department of Neurosurgery, Asklepios Klinik Hamburg-Altona, Germany (2) University Homburg/Saar, Germany INTRODUCTION: Overdrainage in hydrocephalus shunting could be reduced using gravitational driven valves. However, to cope with not exactly known and even changing intra-abdominal pressure and to cope with growing hydrostatic pressure difference in growing children, a programmable gravitational valve is needed. Since December 2008 a first device (programmable Shuntassistant: proSA) is available. To get first and extensive experience about effectiveness, safety and problems a prospective multicenter register/study was launched in 2009. MATERIALS AND METHODS: To evaluate effectiveness of proSA, indication of shunt implantation, patients outcome, ventricular size, need of reprogramming with clinical outcome, overdrainage and underdrainage and implantation sites (retroauricularly or thoracically) were monitored. To get enough information the study is planned for 120 cases with a follow-up of 12 months. The results 71

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 will be statistical evaluated by an independent institute. The study was approved by the ethical committee of the medical association Hamburg (Reg.No: PV 3132) as well as by the local ethical committees. RESULTS: The registry/study started in 2009. 17 centers applied to take part in Prosaika. So far 7 different center included 31 patients (February 2010). Patients’ inclusion will be finished probably in summer 2010, patients’ follow-up will be finished in summer 2011. DISCUSSION: Prosaika will give us preliminary answers about effectiveness, indications and problems of the first programmable gravitation-driven device for hydrocephalus shunting. These results should help to improve indications for proSA and to avoid complications. From this point new hypothesis’s can be generated for comparative studies to find the best shunt solution for hydrocephalic patients. O61. BRAIN LOCALIZATION OF LEUCINE-RICH Α2 GLYCOPROTEIN AND ITS ROLE Nakajima M.1, Miyajima M.1, Ogino I.1, Hagiwara Y.2, Arai H.1 (1) Department of Neurosurgery, Juntendo University School of Medicine, Japan (2) Department of Pathology and Oncology, Juntendo University, School of Medicine, Japan INTRODUCTION: We have previously reported that the level of leucine-rich alpha-2-glycoprotein (LRG) expression is specifically increased in iNPH cerebrospinal fluid (CSF). The objectives of this study are to examine the localization of LRG – the cerebral areas where it is expressed. MATERIALS AND METHODS: The histological sections of several human brain areas taken at autopsy of 50 to 60 years olds and 70 to 85 years olds are prepared, multi-stained with antibodies against human LRG, glial fibrillary acidic protein (GFAP), CD31 and Aquaporin4 (AQP4), and reviewed for the expression sites of LRG. RESULTS: Immunostains of GFAP and LRG were compared in standard brain specimens from elderly males. The results indicated that LRG is distributed throughout the entire brain, with especially high expression in the deep cerebral cortex. In addition, the cells that express LRG showed similar morphology to astrocytes. Double staining of CD31 and LRG revealed a significant expression of LRG in the pericapillary regions. The expression was observed in some astrocytes, as well as in the capillary vessel to which astrocytic processes grow and adhere. When age-related comparisons were made between senile and adult specimens, LRG expression showed in some astrocytes and capillary vessels, increasing with age. Very intense AQP4 immunoreactivity was detected in the perivascular astrocytes that decreased with aging. We found negative correlation between AQP4 and LRG. DISCUSSION: LRG is highly expressed in the deep cerebral cortex and increases with age advancement. LRG is expressed in astrocytes, with high expression observed in the periphery of vessels to which astrocytic processes attach.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0

Poster Presentations (P) P01. POSTCRANIECTOMY HYDROCEPHALUS Venetikidis A., Paleologos T.S., Markellos A., Papanikolaou P.G., Stamatiou S., Voidonikolas L., Georgoulis G., Damilakis K., Kiriakou T. Department of Neurosurgery, General Hospital Nikaia-Piraeus, Greece INTRODUCTION: Large cranial defects combined with hydrocephalus after decompressive craniectomy are a common entity among patients with head trauma. Typically, a shunt is first used to relieve the hydrocephalus. Postcraniectomy hydrocephalus due to CSF circulation disturbancy in such cases is well known. We present a series of such patients managed in our Department. MATERIALS AND METHODS: During the last 5 years, we performed decompressive craniectomy in 69 patients with severe head trauma or other intracranial lesions with intractable brain swelling. Nine patients (13%) developed postcraniectomy hydrocephalus with symptoms and signs of raised intracranial pressure and neuroradiological findings of brain herniation at the site of bone lesion. RESULTS: These nine patients underwent a ventriculoperitoneal shunt. All patients experienced a neurological improvement with neuroimaging resolution of hydrocephalus. There were 2 cases (22%) of over or underdrainage trated with a programmable valve. There were no postoperative infections. All patients were treated later with a cranioplasty without any considerable complications. DISCUSSION: Development of post craniectomy hydrocephalus in patients with severe head injury may deteriorate their neurological condition. Treatment with CSF shunt preferably with programmable valve which can be modulated accordingly, may be a safe and effective management. This method is safe and easy and facilitates the cranioplasty procedure while reducing the potential complications, including intracranial haematoma, effusions and infections, and improves the patient’s outcome. P02. POST-TRAUMATIC HYDROCEPHALUS IN SEVERE HEAD INJURY - SERIES OF 9 CASES Syrmos N.1, Iliadis Ch.1, Barkatsa V.1, Valadakis V.1, Grigoriou K.1, Gavridakis G.2, Arvanitakis D.1 (1) Department of Neurosurgery, Venizeleio General Hospital, Heraklion, Crete, Greece (2) CT Scan Department, Venizeleio General Hospital, Heraklion, Crete, Greece INTRODUCTION: Post-traumatic hydrocephalus is a frequent and serious complication that follows a severe traumatic brain injury. Its incidence varies greatly, largely based on different criteria for its diagnosis. However post-traumatic hydrocephalus, could greatly impact morbidity following a traumatic brain injury and could result in increased mortality if it is not recognized and treated. MATERIALS AND METHODS: 9 patients with post-traumatic hydrocephalus were retrospectively reviewed during the last 4 years (2005-2008). RESULTS: These 9 patients represented 6,9% per cent of the 144 severe head-injured patients seen at our hospital during that period. Our study found a high incidence of correlation between post-traumatic hydrocephalus and decompressive craniectomy. The late effect of decompressive craniectomy may cause CSF blockage around the convexities and hydrocephalus. The diagnoses were based on clinical manifestations and CT scan appearances. The outcome was related closely to the initial GCS score and the method used for diagnosis. DISCUSSION: Late neurological deterioration confirmed by CT scan findings was more useful than CT scan findings alone. CSF shunting was effective in patients with ventriculomegaly who had clinical signs and symptoms of increased intracranial pressure from post-traumatic hydrocephalus.

Poster Presentations (P)

P03. LHERMITTE-DUCLOS DISEASE PRESENTING WITH HYDROCEPHALUS: CASE REPORT AND LITERATURE REVIEW Choong Hyun Kim MD PhD, Jin Hwan Cheong MD PhD, Jae Min Kim MD PhD Department of Neurosurgery, Hanyang University, Guri, Korea Lhermitte-Duclos disease (LDD) is a rare cerebellar disorder characterized by focal or diffuse enlargement of cerebellar folia presenting as a slowly growing mass in the posterior fossa. Clinical manifestations are related to a mass effect and secondary obstructive hydrocephalus. Intracranial hypertension syndrome with heasache and ataxia is the most frequent complaint at presentation. Cerebellar sign or symptoms are present approximately 40-50% of the patients. We describe a case of LDD that the patient who had a vertigo, and secondary obstructive hydrocephalus due to posterior fossa mass. A 68-year-old woman was brought to the emergency room for sudden vertigo following several bouts of vomiting and headache. There was no external sign of trauma, serious illness or infection. On admission, he was alert and had no neurological deficits. Brain computed tomography (CT) and magnetic resonance (MR) images showed hydrocephalus and a cerebellar mass, which compressed 4th ventricle. Craniotomy and subtotal tumor removal was performed. Pathological study of the surgical specimen showed the abnormal, ganglionic neurons, and enlarged molecular layer compatible with gangliocytoma. The patient was uneventful, postoperatively. Cytoreduction can achieve the improvement of symptoms caused by mass effect, but post-operative swelling may aggravate the symptoms. So, if symptomatic, shunting procedure may be the other option of management in the respect of its benign nature. KEYWORDS: Gangliocytoma, Lhermitte-Duclos, disease Cerebellar signs, Shunt. P04. RARE ABDOMINAL COMPLICATIONS OF VENTRICULO-PERITONEAL (VP) SHUNTS Paidakakos N., Rokas E., Theodoropoulos S., Dimogerontas G., Rovlias A., Makrigiannakis G., Papadopoulos M., Konstantinidis E. Department of Neurosurgery, Asclepeion General Hospital of Voula, Athens, Greece INTRODUCTION: Ventriculo-peritoneal (VP) shunting used in the treatment of hydrocephalus is associated with several complications. We report four cases of unusual abdominal complications. MATERIALS AND METHODS: Retrospective clinical review. 4 adult patients (3 males, 1 female; age range 27-44) were admitted for abdominal complications secondary to VP shunting. A giant peritoneal pseudocyst, a right subdiafragmatic abscess, an extrusion of the peritoneal catheter through the anus and a migration of the peritoneal catheter into the abdominal cavity were identified. Free disease interval was 10 years, 1 month, 2 years, and 15 years respectively. RESULTS: Treatment was surgical in 3 cases, surgical combined to endoscopical in 1. All patients demonstrated clinical improvement. DISCUSSION: Abdominal complications of VP shunts are not unusual - a 25% incidence is described in the literature. Awareness of those conditions, even the rare ones previously described, is essential for their immediate management.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 P05. INFECTIONS AFTER CEREBROSPINAL FLUID SHUNT IN ELDERLY PATIENTS Syrmos N.1, Iliadis Ch.1 , Barkatsa V.1, Valadakis V.1, Grigoriou K.1, Gavridakis G.2, Arvanitakis D.1 (1) Department of Neurosurgery, Venizeleio General Hospital, Heraklion, Crete, Greece (2) CT Scan Department, Venizeleio General Hospital, Heraklion, Crete, Greece Infections are major complications of cerebrospinal fluid shunting in the treatment of hydrocephalus and other conditions with obstructed cerebrospinal fluid circulation Cerebrospinal fluid shunts used to control these conditions are prone to colonization particularly by Staphylococcus epidermidis. The incidence is high and this is probably due to prolonged hospital stay as a result of the underlying pathology. There are several pitfalls in diagnosis, particularly in the elderly (>65 years). Treatment of shunt infections should include removal of the colonized shunt, though regimens to avoid this are currently being investigated. Intraventricular therapy with vancomycin along with intravenous rifampicin offers the best chances of success at the first attempt. Shunted patients who contract purulent bacterial meningitis should not have their shunts removed but should be treated in the same way as those without shunts. In this retrospective study 35 first-time shunted elderly patients with hydrocephalus operated were investigated with special reference to the infection rate and to the influence of the following variables: time period, age of the patient, length and time of the operation and the exact placement of the distal drain. The overall infection rate for all implanted CSF shunts was 8,5%. Shunt infection is still a major complication. It is not possible to relate any main cause to the infection rate. The literature recommends removal of the infected shunt combined with antibiotics. The use of prophylactic antibiotics is still controversial. P06. VENTRICULOATRIAL SHUNTS: PREDICTORS OF FAILURES Batra S., Solomon D., Moghekar A., Blitz A., Rigamonti D. INTRODUCTION: Ventriculoatrial (VA) shunts are useful alternatives to ventriculoperitoneal (VP) shunts in patients who fail to respond to VP shunts or when VP shunts are contraindicated. The risk profile for shunt failure with VA shunts may differ from other shunt configurations. We reviewed our long term experience with VA shunts to identify factors contributing to shunt failure. MATERIALS AND METHODS: Between 1995 and 2008, 228 VA shunts were placed in 148 patients by a single neurosurgeon. We retrospectively reviewed surgical technique and long term follow-up to evaluate predictors of shunt failure. The patient population included 70 (47.3%) patients with communicating hydrocephalus, 46 (31.1%) with pseudotumor cerebri syndrome and 32 (21.6%) with congenital/ obstructive hydrocephalus. VA shunt was the primary treatment in 71 patients. Sixty-four shunts were inserted in patients with a history of previous shunt infection. Shunt failure was defined as need for shunt revision. The time-to-failure and predictors of failures were analyzed using Kaplan Meier survival analysis and Cox proportional hazard model, respectively. RESULTS: 110 (48.25%) shunts underwent revision over a mean follow-up of 14.4+ 16.8 months. Median time to VA shunt revision was 19.9 months. Insertion of an additional anti-siphoning device (for symptoms of overdrainage) accounted for 15.5% (17) of revisions. Patients with history of past shunt revision had a median time to revision of 13.7 months versus those without preceding shunts of 39.5 months. Patients with past shunt infection had a median time to revision of 2.4 months versus 24.4 months in patients without past infection. To evaluate the effect of surgeon’s experience, revision rates were compared between the first and last chronologic quartile for events within 1st year of follow-up. Amongst the 57 shunts placed in first quartile 23 (40.35%) failed while of the 57 placed in last quartile 11(19.30%) failed (Overall chi2 (7) = 48.681, p< 0.001; Chi2 for trend =15.258, p< 0.001). Multivariate analysis revealed past shunt revision (odds ratio 2.37, 95% CI: 1.33-4.20, p=0.003), 76

Poster Presentations (P)

previous infection (odds ratio 2.42, 95% CI: 1.42-4.16, p=0.001) and age at shunt placement (odds ratio: 0.98, 95% CI: 0.97-0.99, p=0.007) to be statistically significant determinants of shunt failure. DISCUSSION: VA shunt placement has a learning curve and surgeon’s experience plays a significant role in shunt survival. Shunt failure occurs significantly sooner in patients with previous shunt surgery or shunt infection. P07. ENDOSCOPIC BRAIN-WASHING ON TREATMENT OF VENTRICULAR INFECTION Qing Xiao, Guo-qiang Chen, Jia-ping Zheng, Jin-ting Wu, Hui Liang, Huan-cong Zuo Department of Neurosurgery, Yuquan Hospital, Tsinghua University, Beijing, China INTRODUCTION: To study the effect of endoscopic brain-washing for the treatment of severe ventricular infection. MATERIALS AND METHODS: 60 cases of severe ventricular infection were treated with endoscopic brain-washing under flexible neuron-endoscope from Febrary, 2007 to November, 2009. Among them, 41 cases were secondary to V-P shunt, 13 cases were secondary to external ventricular drainage due to intraventricular hemorrhage or traumatic hydrocephalus, 4 cases were secondary to other neurosurgical operations and 2 case was due to tuberculous meningitis. RESULTS: Of all the 60 patients, 25 (41.7%) were negative in CSF bacterial culture, 27 (45.0%) were infected with general pyogenic bacteria such as staphylococci, streptococcus pneumoniae, Enterococcus faecalis, Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii. 3 (5.0%) were infected with Pseudomonas aeruginosa, 3 (5.0%) were fungal infection, 2(3.3%) were infected with tubercle bacillus. 26 (43.3%) cases of ventricular infection were cured with successful removal of shunt or external ventricular drainage (EVD) by single endoscopic brain-washing. Of 34 (56.7%) whose endoscopic brain-washing were followed by EVD and intraventricular injection of antibiotics, the EVD duration was 4 to 76 d (mean 20.1d), the second V-P shunts was unavoided due to intracranial hypertension after removal of EVD in 7 (11.7%), and dead in 5 (8.3%). All dead cases were infected with Pseudomonas aeruginosa or fungus which were extensive drug resistant. DISCUSSION: Severe ventricular infection was troublesome in neurosurgery. Brain-washing under flexible neuron-endoscope can shorten the course and improve the effect of the treatment of severe ventricular infection. KEYWORDS: Endoscopic brain-washing; ventricular infection. P08. A 40-YEAR SERIES WITH 1070 SYRINX- AND CHIARI-PATIENTS Aschoff A.1, Akbar M.2, Wiedenhöfer B.2, Muhcu S.1, Orakcioglu B.1, Geletneky C.1 (1) Department of Neurosurgery, University of Heidelberg, Germany (2) Department of Orthopaedics, University of Heidelberg, Germany INTRODUCTION: Since 1983 the MRI has solved most of the diagnostic problems of syringomyeliaChiari and led to a steep increase of published operations. MATERIALS AND METHODS: Since 1970 we collected 1070 patients with syringomyelia and Chiari. Except for tumorous cases the most were operated by the first author. 32.7% had a foraminal syringomyelia/Chiari, each 26.0% an idiopathic / posttraumatic syrinx; 7.9% were postarachnoiditic, 5.5% tumor-associated and 1.9% vascular-malformative. We carried out 455 operations in 360 patients; including externally cases, we overview 660 procedures in 423 patients. We used preferebly decompressive duraplasties and syringo-subarachnoid micro-shunts. Follow-up 1 month to 40 years. RESULTS: The best results showed patients with Chiari and posttraumatic syringomyelia (success 77

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 >90% vs. 80%). Idiopathic cases were less successful, arachnitic patients presented often problems. 4 patients died pre- and 2 postoperatively (not OP-related). The decompressive duraplasty showed good results in Chiari patients. In 50% the arachnoidea could be preserved; a tonsillar resection seems not necessary. Surprisingly decompressions in other syrinx-types led relatively often to retethering and recurrences. In thoracic posttraumatic syringomyelias syringo-subarachnoid microcatheters are more simple and comparable in long-term results. After 13 (external) endoscopic and 1 LASERprocedures 11 patients acquired new neurodeficits in part with wheelchair-dependency (2) or serious new pain (3). DISCUSSION: In foraminal cases the decompression is the first choice and controversial in details only. Our good long-term-experiences with microcatheters in posttraumatic syringomyelia are in contrast to disappointing published results, usually with standard catheters. In our opinion there is more evidence for a multi- than for a monocausal hydrodynamic etiology. KEYWORDS: Syringomyelia, Chiari, Decompressive Surgery, Syrinx-microcatheters. P09. EXPRESSION ANALYSIS OF HIGH MOBILITY GROUP BOX-1 PROTEIN (HMGB-1) IN THE CEREBRAL CORTEX, HYPPOCAMPUS, CEREBELLUM OF THE CONGENITAL HYDROCEPHALUS RAT (H-TX) Mitsuya Watanabe MD, Masakazu Miyajima MD, Madoka Nakajima MD, Hajime Arai MD, Ikuko Ogino, Sinji Nakamura, Miyuki Kunichika Department of Neurosurgery, Juntendo University, Bunkyoku, Tokyo, Japan High Mobility Group Box-1 Protein (HMGB-1), a protein expressed highly in developing neurons, is involved in the development and differentiation of neurons. At the same time, it functions as a transcriptional regulator of particular genes and as a cytokine: HMGB-1 released from a defective cell has been reported to induce damage to the adjacent cells. With the view of examining the relationship between neuronal damage caused by hydrocephalus and HMGB-1, we analyzed the expression of HMGB-1 in the cerebellum, cerebrum and hippocampus of one-day-old congenitally hydrocephalic H-Tx rats. As opposed to non-hydrocephalic H-Tx rats, the hydrocephalic H-Tx rats were observed to show stronger expression of HMGB-1 in the cerebellum, cerebrum and hippocampus. Consequently, the protein was presumed to influence the development of neurons from an early postnatal stage not only in the cerebral cortex and hippocampus but also in the cerebellum, which is less susceptible to the direct effects of hydrocephalus. We expect that, in the future, regulating the expression or functions of HMGB-1 will lead to the possibility of impeding the progress of neuronal damage caused by hydrocephalus. KEYWORDS: Congenital hydrocephalus, High Mobility Group Box-1 Protein (HMGB-1), H-Tx rat. P10. ATYPICAL MENINGIOMA IN THE POSTERIOR FOSSA ASSOCIATED WITH COLPOCEPHALY AND CORPUS CALLOUS AGENESIS Choong Hyun Kim MD PhD, Jin Hwan Cheong MD PhD, Jae Min Kim MD PhD Department of Neurosurgery, Hanyang University, Guri, Korea We report a 67-year-old woman with atypical meningioma in the posterior fossa and co-existence of colpocephaly. She presented with headache and dizziness over 2 months. Colpocephaly is an abnormal enlargement of the occipital horns - the posterior or rear portion of the lateral ventricles (cavities or chambers) of the brain, and has been found association with several abnormalities of the brain. It is misdiagnosed as hydrocephalus occasionally. Various etiologies have been postulated 78

Poster Presentations (P)

genetic disorders and error of morphogenesis. On the other hand, frequent chromosomal losses have been observed in the malignant and atypical meningiomas. We report an uncommon case with atypical meningioma in the posterior fossa and co-existence of colpocephaly, and discuss its pathogenesis and review the pertinent literatures. P11. EFFECT OF ANTIBIOTIC IMPREGNATED SHUNTS ON INFECTION RATE IN ADULT HYDROCEPHALUS: A SINGLE INSTITUTION’S EXPERIENCE Harrison Farber S., Parker S.L., Adogwa O., McGirt M.J., Solomon D., Rigamonti D. Departments of Neurology and Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, USA INTRODUCTION: Infection is a severe complication treatment shunt insertion, occurring in 5-15% of patients. A lower incidence of infection has been reported with use of antibiotic impregnated shunts (AIS), however most of the evidence is available for pediatric series. We describe our experience regarding efficacy of AIS as prophylaxis against shunt infection in adult patients. MATERIALS AND METHODS: A retrospective review of 500 shunts placed between August 2002 and April 2009 was undertaken. AIS catheters were used in 250 (50%) procedures and non AIS catheters were used in 250 (50%) surgeries. The diagnoses included hydrocephalus in 378 (76%), pseudotumor cerebri in 83 (17%), and other causes in 40 (8%) patients. The types of shunts placed included 314 Ventriculoperitoneal shunts (63%), 15 ventriculopleural shunts (3%), and 170 ventriculoatrial shunts (34%). The incidence of shunt infection was compared between the patients who received AIS and non-AIS catheters. Shunt infection was defined as fever/leukocytosis, or wound dehiscence with positive cultures. RESULTS: The patients who received AIS catheters had significantly fewer shunt infections. Three patients (1.2%) with antibiotic-impregnated catheters experienced shunt infection within the 9.1 month follow-up period, whereas ten patients (4.0%) with non-impregnated catheters experienced shunt infection (p < 0.0492) in the 9.5 months of follow-up. DISCUSSION/ CONCLUSIONS: AIS is effective in reducing the shunt infection in patients. P12. THE OBSTRUCTIVE NATURE OF PEDIATRIC HYDROCEPHALUS RESULTS OF A HIGH-RESOLUTION MRI STUDY Schuhmann M.U.1, Filip Z.1, Ries B.G.2, Tatagiba M.S.1, Nägele T.1 (1) Section of Pediatric Neurosurgery, Department of Neurosurgery, Eberhard Karls University Hospital, Tuebingen, Germany (2) Department of Neuroradiology, Eberhard Karls University Hospital, Tuebingen, Germany INTRODUCTION: Modern theories and approaches suggest that there is no malresorptive or communicating hydrocephalus. Traditionally, cases were termed mal- or aresorptive, if imaging did not reveal an obvious intraventricular obstruction. Standard MRI sequences are blind to subtle pathology of the CSF spaces. We used high-resolution MRI to prospectively investigate new cases of hydrocephalus or at the time of shunt-malfunction. MATERIALS AND METHODS: To image CSF spaces in 1.5 T MR scanners we performed - in addition to T2-SE sequences - a incubator-coil operated high-resolution T2-sequence (newborns/premature babies, SL1-2 mm, TR5711, TE120), a 3D-CISS sequence (SL0.7 mm, TR12.06, TE6.03) or a 3D-trueFISP sequence (SL1 mm, TR4.97, TE2.49). RESULTS: 42 children were recruited and we performed 11 HR-T2, 7 CISS and 28 trueFISP studies. All 21 children with post-hemorrhagic hydrocephalus showed obstruction - alone or in combination 79

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 - at the following sites,: cerebral aqueduct, fourth ventricular outlet, craniocerebral junction, basal cisterns. In 13 children aquaeductal stenosis or occlusion and in 3 Blake‘s Pouch was established. In one a suprasellar arachnoid cyst was found. MRI could not establish the site of obstruction in two children, despite the fact that both showed lowering of third ventricular floor. DISCUSSION: In almost all cases of non-spina bifida pediatric hydrocephalus high resolution MRI revealed an obstructive component. Fourth ventricular dilatation indicates outflow obstruction and not „communicating hydrocephalus“. The visualization of multiple suprasellar and retroclival membranes is important regarding indication for third ventriculostomy. Pediatric hydrocephalus is predominantely obstructive. P13. SHUNT RELATED OCCLUSIVE EXTERNAL HYDROCEPHALUS Zinenko D. Moscow Pediatric and Children Surgery Research Institute, Russia It’s well known that only 60-80% of CSF is produced inside ventricles, rest is produced on the surface of the brain. From another side we know that hydrocephalus might be obstructive (when all or part of ventricles are separated from other compartments of CSF spaces), and communicating hydrocephalus (when we have obstruction of CSF pathways outside ventricles). In literature we didn’t found description of conditions when obstruction on the level of the ventricles exist simultaneously with insufficient resorption or obstruction or obstruction outside ventricles. This situation became obvious only after insertion of the shunt. Clinical signs depends of reason of CSF dynamic dysfunction. If we have second of obstruction on the level of basal cisterns- symptoms are equal to symptoms of trapped forth ventricle. If we have obstructive hydrocephalus with malresorption it looks like pseudotumor or slit ventricles syndrome with increased ICP. Conservative treatment is useless and only connecting of separated spaces with shunted spaces can solve the problem. This conditions can’t be called external hydrocephalus because such condition doesn’t exist and we must exclude this diagnose from classification. Before inserting of the shunt we have only internal hydrocephalus because pressure inside the ventricles are higher and only after shunt is placed situation changed and outside pressure becomes higher and start to compress brain and ventricles. So we suggest to call this condition when after shunting extracerebral pressure starts to increase and compress the brain like - shunt related occlusive external hydrocephalus (with marking the level of extraventricular obstruction. P14. ICMPLUS SOFTWARE USED FOR ASSESSMENT OF CSF DYNAMICS Czosnyka Z., Czosnyka M., Pickard J.D., Smielewski P. Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK INTRODUCTION: CSF dynamics testing is complex and requires computer support to record and analyse all possible modalities involved in pathogenesis of hydrocephalus. MATERIALS AND METHODS: ICMPlus software was introduced in CSF Dynamics Lab in 2003. Since then 1447 constant rate infusion tests and 123 overnight ICP monitoring (using intraparenchymal bolt) were performed. RESULTS: Various configurations were used: ICP only (identification of CSF dynamics model (Dr. Marmarou) and overnight ICP monitoring with analysis of compensatory reserve and B waves); ICP 80

Poster Presentations (P)

and arterial pressure (analysis of Pressure Reactivity Index); ICP, ABP and Transcranial Doppler Blood flow velocity (for assessment of cerebral autoregulation) ; ICP,ABP and Near-Infrared Spectroscopy (for analysis of fluctuation of Cerebral Blood Volume); ICP, sagittal sinus pressure and jugular vein pressure (in patients with idiopathic intracranial hypertension to assess a hydrodynamic consequences of cerebral venous sinus stenosis). To assess vascular factors of hydrocephalus, combination of CSF infusion study with CO2 reactivity and PET-CBF studies were performed. Software contains database of shunts from Cambridge Shunt Evaluation Laboratory aiding shunt assessment in-vivo in case of possible underdrainage or overdrainage. Software enables digital recording of data, ready for post-hoc manual or batch analysis, creation of virtual signals (as critical closing pressure, cerebral compliance, etc.) and analysis of their dependency on primary modalities. DISCUSSION: Multiple modality data recording supported by identification of CSF compensation model can be used in diagnosing patients with CSF circulation disorders. Collected database of cases and signals forms a powerful reference tool in investigation and understanding of complex mechanism underlying hydrocephalus. P15. PROGRAMMABLE SHUNT ASSISTANT TESTED IN CAMBRIDGE SHUNT EVALUATION LABORATORY Czosnyka M., Czosnyka Z. Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK INTRODUCTION: The ProSA shunt system has been recently introduced into clinical use. The system can be in-vivo adjusted magnetically and this adjustability is supposed to affect CSF drainage only in vertical body position, aiming to prevent posture-related overdrainage. MATERIALS AND METHODS: In the Cambridge Shunt Evaluation Laboratory we tested a combination of adjustable gravitation-compensating device with fixed differential pressure valve. RESULTS: All the shunts showed good mechanical durability and stability of hydrodynamic performance over a 60 days period. 1. The flow-pressure performance curves and operating pressures were stable, fell within the limits specified by the manufacturer, and changed according to the programmed performance levels. 2. The ProSA system has higher than usual hydrodynamic resistance (around 8.8 mm Hg/(ml/min)) in vertical position (but still within the physiological limits of CSF resistance to outflow). It may be helpful in additional control of overdrainage. 3. Operating pressure in vertical position reacts precisely and repeatedly to changes of settings within the limits 0-40 cmH2O. 4. Operating pressure is reduced gradually when axis of the valve declines from vertical to horizontal. It adjusts ‘siphoning-compensation’ action of the system if a patient rests in semi-sitting position. 5. External programming proved to be easy and reliable. 6. Even very strong magnetic fields (3 Tesla MRI scanner) were not able to change the setting of ProSA. DISCUSSION: From the point of view of its hydrodynamic performance, the ProSA in vertical position works as an adjustable valve. In this way it is able to compensate for posture related overdrainage. P16. FAST FOURIER TRANSFORMATION (FFT) FOR ICP SLOW WAVES DETECTION Kiefer M.1, Schmitt M.1, Antes S.1, Krause I.2, Eymann R.1 (1) Department of Neurosurgery, Medical School, Saarland University, Homburg-Saar, Germany (2) Philips Chair for Medical Information Technology, Helmholtz-Institut, Aachen, Germany

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 INTRODUCTION: Methods for automatic intracranial pressure slow waves detection have been explored on the way to establish an automated ICP data analysis. Objective was to analyze the potency of FFT for that purpose. MATERIAL AND METHODS: ICP-monitoring data for 150 patients’ overnight monitoring suspected for chronic hydrocephalus were analyzed. Data were gained with intraventricular ICP-tip sensor devices and stored on a personal computer at 1 Hz. Based on a MATLAB platform several algorithms to determine A- and B-waves’ frequency and amplitude were tested and compared with human experts analysis. RESULTS: Supposing suitable time increment and time window for analysis the frequency of A- and B-wave can be determined using the FFT algorithm in an ICP data file. The results of automated analysis and human experts’ analysis correlated well (p = 0.042). In contrast due to the “leakage effect” of this algorithm it is not suitable for amplitude estimation, which is typically underscored. DISCUSSION: The frequency of slow ICP waves can be determined using the FFT algorithm with excellent results. Yet for the PC-assisted assessment of slow waves’ amplitude other algorithms must be explored. Information lost about waves’ amplitude must be attributed to the leakage effect which is typical for the FFT as it is typically more qualified for rectangular than for sinusoidal shaped waves analysis. Since the sinusoidal shapes are the norm in biological signals, FFT should not be considered as the method of choice for such purpose. P17. EXAMINATION OF DEPOSITS IN CSF SHUNT VALVES USING SCANNING ELECTRON MICROSCOPY Charalambides C., Sgouros S. Department of Neurosurgery, “Attikon” University Hospital, University of Athens, Greece INTRODUCTION: Obstruction remains the most common complication of cerebrospinal fluid shunts. The valve constitutes an important site of potential malfunction either in the form of obstruction, or as impaired CSF regulation. The aim of this pilot study was to investigate the extent and composition of debris depositions along the structural components of the shunt valve. MATERIALS AND METHODS: We examined 4 explanted Medos programmable valves. The valves were stored and examined wet, to exclude any post-explantation crystallization of material. They were cut open and disassembled. All specimens were studied under an SEM (Quanta 200, FEI, Hillsboro, OR) operating at different levels of accelerating voltage and 110μA beam current. The valve areas that were analyzed included the ruby ball and collar, the flat spring with its pillar and the staircase cam. The elemental composition, in areas with abnormal deposits, was subsequently determined by energy-dispersive x-ray microanalysis, EDS using a Si (Li) detector (Sapphire, EDAX, Mahwah, NJ) with super ultrathin Be window. RESULTS: All explanted valves had varying degrees of deposits in all surveyed areas including the ruby seat and the staircase unit. Deposits were present early after implantation. Colonies of bacteria were seen in valves not formally declared infected. Typically, deposits were extensive in performancecritical areas of the valve system. DISCUSSION: Shunt valves are subject to extensive material deposition which appears to take place early after implantation. The effect of these deposits on proper functioning of the valve as well as their pathogenesis is difficult to be established. It seems though that there is scope for improvement of the material that valves are made of.

Poster Presentations (P)

P18. ICP ANALYSIS IN NPH: COMPARISON OF TIME-DOMAIN DERIVED VERSUS FREQUENCYDOMAIN DERIVED PULSE WAVE AMPLITUDE AND RELATED PARAMETERS Schuhmann M.U.1, Buddhakoralage S.1, Speil A.1, Helm J.2, Jaeger M.2, Eide P.3 (1) Section of Pediatric Neurosurgery, Department of Neurosurgery, Eberhard Karls University Hospital, Tuebingen, Germany (2) Department of Neurosurgery, University of Leipzig, Leipzig, Germany (3) Department of Neurosurgery, Rikshospitalet, Oslo University Hospital, Oslo, Norway INTRODUCTION: Computerized overnight ICP monitoring (COM) and lumbar infusion study (LIS) are established supplementary investigations in suspected iNPH. ICP pulse amplitude can be determined by frequency-domain and time-domain analysis. We compared both methods to elucidate correlations between approaches. MATERIALS AND METHODS: COM and LIS data from 68 patients were analyzed with ICM+ software (frequency-domain pulse amplitude (AMP)) or Sensometrics software (time-domain pulse amplitude (Amp)). Sensometrics calculates meanAmp and percentage of monitoring-time where Amp is >3,4,5,6, or 7 mmHg (%MT). ICM+ calculates also the RAP coefficient, related to reserve capacity/compliance. From LIS data ICM+ calculates resistance to CSF outflow (Rout), Elastance (E) and Pressure Volume Index (PVI). Correlation analysis was performed. RESULTS: AMP correlated well to meanAmp (r=0.64, p<0.0001) and %MT (r=0.61-0.9, p<0.0001). RAP didn‘t correlate to meanAmp but to %MT (up to r=0.39, p<0.004). PVI/E didn‘t correlate to COM data at all. Rout correlated to Amp and AMP. Sensitivity/specificity of clinical outcome prediction according to a) Amp analysis and b) RAP&E was 0,79 / 0.45 and 0.79/0.89 respectively. DISCUSSION: Frequency- and time-domain ICP amplitude do correlate well. Reserve capacity (RAP) correlated to %MT but not to amplitudes. The lacking correlation of E/PVI to amplitudes and RAP might be related to a missing direct linkage of mechanisms behind E/PVI and the patients „position“ on the pressure volume curve (RAP/amplitudes). P19. AN INNOVATIVE PERMANENTLY IMPLANTED WIRELESS INTRACRANIAL PRESSURE MONITOR USING MEMS TECHNOLOGY AND MICROWAVE TELEMETRY FOR THE DIAGNOSIS OF HYDROCEPHALUS Kralick F.A.1, Kawoos U.2, Warty R.3, Tofighi M.R.4, Rosen A.2 (1) Department of Neurosurgery, Hahnemann University Hospital, Philadelphia, USA (2) Department of Biomedical Engineering, Drexel University, Philadelphia, USA (3) Department of Electrical Engineering, Philadelphia, USA (4) Penn State University, the Capital College, Middletown, USA INTRODUCTION: To fabricate and test a microelectrical mechanical intracranial pressure sensor with microwave transmission for the accurate measurement of intracranial pressure over long durations in an aqueous environment. Toxicity and tissue changes were analyzed in a swine model. MRI compatibility was also tested. MATERIALS AND METHODS: The original sensor was fabricated by using 12mm diameter casing with pzt system. It utilized bioMEMS sensor with telemetry using microwave transmission at 2.4GHz. A phantom gel was utilized to measure pressure in a variety of pressures and the results recorded in a model that simulated an adult skull. This was compared with a Camino intracranial pressure sensor (Camino Laboratories, San Diego, CA) place in the contralateral side of the model. The function of the MEMS sensor was also plotted in an aqueous environment. A swine model was used to determine proof of implantation and obtain tissue toxicity data. 83

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 Placement in MRI was used to determine MRI compatibility. RESULTS: The MEMS device recorded ICP measurements over the course of six months. These pressure values correlated with the results from the Camino ICP sensor. In-vivo swine studies revealed unacceptable thickening of the dura when placed in the epidural space. This dural thickening necessitated a design change that utilized a subdural placement of the MEMS sensor. MRI compatibility studies revealed no alteration in function or significant artifact. DISCUSSION: We have fabricated and demonstrated the accuracy of a MEMS based intracranial pressure sensor that can be interrogated through the scalp via microwave transmission and function for months in an aqueous environment. This ICP sensor can be used to diagnose remotely, numerical values for elevations in ICP as the result of shunt failure for hydrocephalus or neoplastic processes. P20. MICROSTRUCTURAL ALTERATIONS OF SILICONE CATHETERS IN AN ANIMAL EXPERIMENT: HISTOPATHOLOGY AND SEM-FINDINGS Eymann R.1, Kim Y.J.2, Bohle R.M.2, Kiefer M.1 (1) Department of Neurosurgery, Medical School, Saarland University, Homburg-Saar, Germany (2) Department of Pathology, Medical School, Saarland University, Homburg-Saar, Germany INTRODUCTION: Biocompatibility has to be characterized as “inert”, “tolerated” and “bioactive”. Since catheter induced complications are responsible for up to 40% of all shunt-revisions the underlying mechanisms of catheter degradation shall be examined. MATERIALS AND METHODS: In an animal experiment using young rats we implanted 12 different silicon shunt catheters with surface modifications designed to improve biocompatibility. The catheters were fixed by suturing it on the shoulder and the hip in order to simulate the processes in growing children. Another catheter was fixed only on the shoulder and became inserted intraperitoneally up to 10 cm. One year later all catheters were explanted and histopathologically and by SEM examined. RESULTS: Signs of a chronic cellular immune reaction were found around the catheters. Completely organized intraluminal obliteration was seen in 6 intraperitoneally inserted catheters. The tissue growth obviously started at its distal intraperitoneal tip. SEM findings were comparable with our previously published data demonstrating calcifications and varying signs of biodegradation depending on the examined surface modification. DISCUSSION: Hydrocephalus shunt catheters cannot be termed “inert” or “bio-tolerated”. Rather they are bio-active implants according to our findings and international nomenclature. P21. WHAT IS THE APPROPRIATE SHUNT SYSTEM FOR NORMAL PRESSURE HYDROCEPHALUS? Chrissicopoulos C.¹, Mourgela S.¹, Kirgiannis K.¹, Petritsis K.¹, Ampertos N.¹, Sakellaropoulos A.², Spanos A.¹ (¹) “Agios Savvas” Anticancer Institute, Department of Neurosurgery, Athens, Greece (2) “Neon Athineon” Hospital, Pulmonary and Critical Care Medicine, Athens, Greece INTRODUCTION: Normal pressure hydrocephalus (NPH) is the symptomatic occult hydrocephalus with normal cerebrospinal fluid pressure. A question is “What type of shunt system is best?”. We report this case in order to denote that there is still need for more precise valve pressure determination. MATERIALS AND METHODS: A 72-years-old man presented with dementia, abnormal gait and urinary incontinence. Brain Computed tomography (CT) revealed ventricular enlargement. Cisternography revealed normal cerebrospinal fluid pressure and communicating hydrocephalus. A programmable valve was implanted right parietal at high pressure. Postoperatively the symptoms 84

Poster Presentations (P)

subsided. New brain CT revealed a subdural hematoma in the site of valve implantation. By lowering the valve pressure the patient became symptomatic and the hematoma was enlarging. After evacuation of the subdural hematoma and by elevating the valve pressure the patient recovered. DISCUSSION: The typical NPH cases with symptoms respond to a shunting operation. The goal of therapy is reduction of the ventricular size. Most studies performed for evaluation of NPH patients such as neuroimaging techniques, removal of CSF and cisternography do not always predict the outcome after shunting. DISCUSSION: Since we do not have tests with predictive accuracy the treatment for suspected NPH ranges. Although the existence of many choices of shunts devices there is still need for more precise determination of valve opening pressure. We should perform an ideal shunting operation using an appropriate shunt system. P22. SURGICAL MANAGEMENT OF ADULT CHRONIC HYDROCEPHALUS BY USING VENTRICULO-PERITONEAL SHUNTS WITH ADJUSTABLE VALVES Paidakakos N., Rokas E., Theodoropoulos S., Dimogerontas G., Makrigiannakis G., Rovlias A., Papadopoulos M., Konstantinidis E. Department of Neurosurgery, Asclepeion General Hospital of Voula, Athens, Greece INTRODUCTION: To evaluate our experience with adjustable cerebrospinal fluid shunt diversion systems in treating chronic hydrocephalic conditions and to assess the difficulty in selecting and predicting the most suitable valve opening pressure for the individual patient during insertion. MATERIALS AND METHODS: Retrospective study including 38 patients, 28-85 years old (mean age 62.8). Assessment of management of the following conditions is discussed: idiopathic normal pressure hydrocephalus (16 patients), obstructive hydrocephalus secondary to trauma (9), tumor (5), subarachnoid hemorrhage (6), meningitis (1), and pseudotumor cerebri (1). The average opening pressure selected at implantation was 100 mmH2O for iNPH, 110 mmH2O for obstructive hydrocephalus, and 90 mmH2O for pseudotumor cerebri. Cranial x-rays were used to verify the selected setting. Follow up was 6 to 24 months. A CT scan was obtained both pre- and 3 months post-operatively (Evan’s index). RESULTS: 21 patients obtained immediate clinical benefit, with no need of further adjustments during the follow up period. The other 17 patients needed from to 1 to 3 further adjustments (mean 1.6). On average the pressure was adjusted by 23.3 mmH2O in the iNPH group as compared to 26.6 mmH2O in the obstructive hydrocephalus group. The majority of adjustments were performed within 2 months of implantation. All but 4 out of these 17 patients improved after final adjustment. There was shunt obstruction in 3 patients and infection in 1 (surgical revision required). DISCUSSION/CONCLUSIONS: A significant number of patients (44.7%) needed further adjustments; this fact supports the use of adjustable systems. iNPH patients needed more adjustments to optimally calibrate the valve.

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 P23. ADJUSTABLE GRAVITATIONAL VALVES – TECHNICAL OVERKILL OR NECESSITY? Aschoff A.1, Kiefer M.2, Kehler U.3, Jung C.1, Dictus C.1 (1) Department of Neurosurgery, University of Heidelberg, Germany (2) Department of Neurosurgery University of Homburg/S, Germany (3) Department of Neurosurgery, Asklepios Klinik Hamburg-Altona, Germany INTRODUCTION: 80 gravitational (g)-valve-studies show usually reduced quotes of overdrainage and subdurals. However, suboptimal pressure-selection requireing revisions remained a problem, especially in growing children and adipous. In 1996 we suggested adjustable g-valves and developed seven concepts in 2000. The idea was picked up by Miethke, who patented a first “ProSA” in 2004 and launched the final version in 12/2008. MATERIALS AND METHODS: An excenter fixed on a magnetic rotor varies the tension of a spring counteracting the weight of a gravitational ball. The opening pressure in vertical can be changed stepless between 0-40 cmH2O. A “brake” excludes unintentional disadjustments by magnets/MRI up to 3 T. The implantation is possible on thorax or lateral head. Like in all g-valves a strict vertical orientation on the longitudinal body axis is essentially. The ProSA can be combined with any simple or adjustable DP-valve. RESULTS: Since 12/2008 we implanted 15 ProSAs, 14 secondary in “complicated” cases (71 previous OPs, max. 10), 1 primarily; 3 additional patients had external ProSAs. No technical ProSAproblems, 20 successful adjustments, but 2 transfers from (adipous) thoraxes to head due to difficult adjustment. Valve-independent revisions such as infection (1; 5.6%), catheter problems (4; 22%) were standard. The outcome was good in 11 and fair in 2 patients. A poor-grade trauma remained vegetative. 2 psychosomatic cases had normal ICPs, but intractable vomitus respect. meteorism. 8 ICP-measurements showed physiological ICPs in all positions, in part after valve readjustment. DISCUSSION: Adjustable g-valves are a consequent further step of shunt technology. Special indications may be children and difficult hydrocephali. KEYWORDS: Hydrocephalus, Shunt, Adjustable gravitational valve, ICP-measurement. P24. ADULT ENDOSCOPIC THIRD VENTRICULOSTOMY IN OBSTRUCTIVE HYDROCEPHALUS Woodworth G.F., See A., Batra S., Jallo G.I., Solomon D., Rigamonti D. Departments of Neurology and Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, USA INTRODUCTION: Endoscopic third ventriculostomy (ETV) is being used increasingly in adults and children with non-communicating hydrocephalus as an alternative to CSF shunting. With the clear advantage of no implanted hardware prone to failure and infection, the durability, patient selection issues, and potential complications associated with ETV need to be better defined to adequately assess the costs and benefits relative to CSF shunts. MATERIALS AND METHODS: One hundred and twenty four consecutive adult patients (>18 yrs) treated with ETV at a single institution were retrospectively reviewed to identify clinical and radiological predictors of success and failure of ETV. Sufficient data were available on 103 patients. Primary end point was failure of ETV requiring shunt placement. Secondary endpoint was clinical relapse accompanied by radiological features of decompensated hydrocephalus. Associations with ETV failure were assessed via Cox proportional-hazards regression analyses. RESULTS: Clinical improvement was seen in 76 (74%) patients within a median of 1 month following surgery. Radiographic improvement was seen in 59 (57%) patients within a median of 2 months after surgery. 57 (55%) of the patients remained improved through last follow-up, a median of 5 86

Poster Presentations (P)

months (range 0-93 months) following ETV. Multivariate associations with ETV success included: peri-operative steroid use, intra-operative image guidance, post-operative subdural collection, decreasing time to radiographic improvement, and fewer previous shunt revisions. DISCUSSION: ETV is an effective procedure in well-selected, adult patients. Our results suggest that patients with a history of numerous shunt revisions may fail ETV treatment. Peri-operative steroids and intra-operative image guidance may improve ETV success rates. Shorter time to radiographic improvement is associated with higher likelihood of ETV success. P25. EFFICACY AND SAFETY OF THE 2MICRON CONTINUOUS WAVE LASER IN NEURO-ENDOSCOPIC PROCEDURES Schuhmann M.U., Nagel C., Ebner F.E., Tatagiba M.S. Section of Pediatric Neurosurgery, Department of Neurosurgery, Eberhard Karls University Hospital, Tuebingen, Germany INTRODUCTION: The 2micron continuous wave laser combines high tissue effectiveness like CO2 laser with hemostatic capacity of Nd:YAG laser, with a maximal tissue penetration of 1(-2) mm. This renders the laser useful for intraventricular neuro-endoscopy. We report on a prospective consecutive series of pediatric and adult patients. MATERIALS AND METHODS: Within 8 months the laser was used in 32 procedures, performed in 12 children (median 3y 2mo) and 16 adults (median 44.5y). The laser fibre, advanced through the working channel, was used for all manipulations. RESULTS: In obstructive hydrocephalus we performed 18 primary ETVs and one repeat-ETV. In addition there were: 2 septostomies (s.pellucidum), 2 fenestrations plus shrinkage-remodeling of suprasellar arachnoid cysts, 1 removal colloid cyst, fenestration of 1 intraventricular cyst, 2 mid brain cysts and 1 cysto-ventriculostomy. In 4 tumor-biopsies laser was used for hemostasis. In all fenestrations/stomies the laser totally replaced mechanical devices. The use of mono-/bipolar coagulatioin was never necessary. There was no vascular injury and no clinical sequelae. DISCUSSION: The 2micron laser is ideally suited for intraventricular neuro-endoscopy, since it enables save and fast fenestrations without the necessity to change to any other instrument in most cases. Hemostatic capacity is very good. It is safe regarding injury to cisternal arteries or neighboring structures. Compared to mechanical devices it is much better suited to perform fenestration from a steep angle and into floppy walls. It has become our No. 1 tool in intraventricular neuro-endoscopy. P26. BENIGN CEREBRAL AQUEDUCT STENOSIS IN AN ADULT Chrissicopoulos C.¹, Mourgela S.¹, Ampertos N.¹, Sakellaropoulos A.², Kirgiannis K.¹, Petritsis K.¹, Spanos A.¹ (1) “Agios Savvas” Anticancer Institute, Department of Neurosurgery, Athens, Greece (2) “Neon Athineon” Hospital, Pulmonary and Critical Care Medicine, Athens, Greece INTRODUCTION: The cerebral aqueduct (of Sylvius) is a channel that connects the third and fourth ventricles in the midbrain. Normal cerebrospinal fluid circulation requires an open aqueduct. If stenosis exists symptoms of hydrocephalus may appear. We report a case of benign aqueductal stenosis which was an incidental finding. MATERIALS AND METHODS: A 42-years-old patient was suffering from dizziness of one month duration which began by changing head position. He had never headache, nausea or vomiting. Brain computed tomography (CT) and magnetic resonance imaging (MRI) showed a dilatation of third ventricle with a normal appearing 4th ventricle. Cine brain MRI revealed chronic dilatation of lateral 87

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 and third ventricles with stenosis of aqueduct of Sylvius. Meanwhile headache had subsided. DISCUSSION: In obstructive hydrocephalus due to benign aqueductal stenosis in adults, the lack of communication between the ventricles across the tentorium creates a pressure differential between the supratentorial and infratentorial compartments. This creates a significant anatomical distortion of structures located at the level of the tentorial hiatus that is well tolerated because of the slow progression of the aqueductal obstruction. Shunt placement resolves the situation by inverting the pressure differential and reestablishing a normal anatomy. CONCLUSION: In benign aqueductal stenosis there is a critical point that must be reached so that in cases of symptomatology’s compensation the compensatory mechanism not to work and symptoms appear. Benign aqueductal stenosis remains a significant challenge.

Index

Index O. M. I. M. N. K. A. M. S. K. H. G. D. A. G.A. G. A. O. K. V. L.F. S. A. A. N. R. A. E. R.M. P.A. S. D. T. R. T. S. M. L.M. K.G. S.L. C. E. G.Q. J.H. C.

Adogwa Akbar Alafuzoff Alber Ampertos Andersson Andreou Andresen Antes Aquilina Arai Arhontakis Arvanitakis Aschoff Aygok Aygok Baird Balédent Barkas Barkatsa Bátiz Batra Behrens Bevot Biedermann Birgander Blitz Blomsterwall Bohle Boling Borgarello Bouramas Bouras Bouzerar Brinker Buddhakoralage Bunnage Camargo Cesarini Chan Charalambides Chatzidakis Chen Cheong Chrissicopoulos

23, 79 22, 77 31, 59 21, 40 26, 84, 87 24, 44 8, 18, 29 21, 36 21, 25, 31, 33, 36, 59, 69, 81 30, 54 23, 30, 34, 56, 72, 78 8 8, 22, 74, 76 22, 26, 30, 32, 33, 58, 65, 69, 77, 86 31, 32, 60, 63 8, 17, 23 27, 47 24, 31, 41, 42, 43, 61 33, 71 22, 74, 76 27, 47 22, 26, 76, 86 32, 63 21, 40 30, 58 28, 52 22, 76 33, 68 26, 84 32, 63 30, 54 25, 45 30, 55 24, 43 16, 20 25, 83 30,54 27, 47 31, 61 28, 50 25, 82 8, 33, 71 22, 30, 53, 77 22, 23, 75, 78 26, 84, 87

S. A. Z. M. K. K. H. C. G. J.E. F.E. M. R.J. P.K. P. A. E. B. S. R. O. E. A. Z. A.S. E.M. G. N. K. K.N. J. M. M. F.B. R. Y.C. H. G. N. C. G. C. A.M. N. K.

Constantini Currà Czosnyka Czosnyka Damilakis Demura Deramond Dictus Dimogerontas Donahue Ebner Edsbagge Edwards Eide Eide Eklund Elgh Eliceiri ElSankari Eymann Fayeye Fernell Fichten Filip Filippidis Finney Flint Foroglou Fountas Fountas Frankel Fratzoglu Fraunberg Freimann Frič Gan Gatos Gavridakis Gekas Geletneky Georgoulis Gondry-Jouet Gonzalez Graff-Radford Grigoriou

8, 16, 20 30, 58 24, 25, 41, 42, 43, 80, 81 8, 17, 19, 23, 24, 31, 41, 42, 43, 80, 81 22, 74 27, 45 31, 61 26, 30, 32, 33, 58, 65, 69, 86 22, 26, 75, 85 27, 47 26, 87 21, 53, 39, 68 30, 54 30, 57 25, 83 24, 28, 32, 33, 43, 44, 52, 63, 67 32, 63 27, 47 31, 61 21, 25, 26, 31, 33, 36, 59, 69, 81, 84 33, 70 21, 37 31, 61 23, 79 28, 48 27, 47 33, 70 8 8, 33, 68 28, 30, 52, 55 24, 43 33, 71 31, 59 27, 46 30, 57 33, 70 33, 68 22, 74, 76 25, 45 22, 77 1, 22, 74 31, 61 27, 47 8, 18, 29 22, 74, 76 89

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 A. M. K. G. F. Y. M. F.S. M. M. D. P. J. D. M. Ch. T. M. J.E. M. G.I. R. A.J. C.E. BR. M. C.S. C. T. MYS Y. E. E.Z. H. K. U. C. U. N. J. M.

Grotenhuis Guerra Haas-Lude Hadjigeorgiou Hafizov Hagiwara Hamilton Harrison Hashimoto HattoriI Haux Hellström Helm Hertle Högfeldt Iliadis Inagaki Ishikawa Jääskeläinen Jaeger Jallo Jensen Jimenez Johanson Johansson Juhler Jung Jung Kalamatianos Kalani Kanemura Kapsalaki Kapsalaki Kasai Kawamoto Kawoos Kayis Kehler Keong Kestle Kiefer

Ch.H. Y.J. J.M. Y. K.

Kim Kim Kim Kinoshita Kirgiannis

8, 19, 29 27, 47 21, 40 30, 55 21, 39 34, 72 21, 37 23, 79 32, 64 27, 45 30, 32, 33, 58, 65, 69 21, 32, 33, 39, 62, 68 25, 83 30, 58 21, 33, 39, 66 22, 74, 76 21, 40 8, 18, 29, 32, 64 31, 59 25, 83 26, 86 21, 38 27, 47 27, 47 33, 66 21, 28, 36, 38, 49 33, 69 26, 30, 58, 86 30, 56 28, 48 28, 50 28, 52 30, 55 27, 45 21, 40 25, 83 31, 60 26, 34, 71, 86 24, 42 8, 16, 18, 20, 27 18, 21, 24, 25, 26, 29, 31, 33, 34, 36, 42, 59, 69, 71, 84, 86 22, 23, 75, 78 26, 84 22, 23, 75, 78 21, 40 26, 84, 87

T. N. A.P. P. P.M. A. D. E. H.P. C. K. K. F. I. N. T. A. K. G.P. D. V. N. S. H. B. M. M. M. G. J. E. A. A. M. M. M.J. U. M.C. P. W. M. T A. E. S. M. I.

Kiriakou Kitchen Klausner Klinge Klinge Koivisto Kombogiorgas Konstantinidis Koo Koutsarnakis Kouzelis Kouzounias Kralick Krause Kuwana Kyriakou Larsson Laurell Lee Legars Leinonen Lenfeldt Leonhardt Liang Lindquist Loufardaki Luciano Madan Makrigiannakis Malm Markakis Markellos Marmarou Masakazu Mase McGirt Meier Miller Missori Mitsuya Miyajima Miyati Moghekar Mori Mourgela Mpakopoulou Mpaltas

22, 74 33, 66 32, 63 8, 16, 17, 20, 23, 32, 62 27, 47 31, 59 33, 70 22, 26, 75, 85 32, 63 30, 56 5, 7, 8, 16, 17, 19, 20, 23, 34 25, 45 25, 83 24, 25, 42, 81 32, 64 33, 71 28, 52 31, 61 30, 55 31, 61 31, 59 28, 52 24, 42 22, 30, 53, 77 21, 37 30, 56 8, 18, 19, 29, 32 28, 50 22, 26, 75, 85 24, 28, 32, 33, 43, 44, 52, 63, 67 8 22, 33, 71, 74 5, 17, 23, 31, 32, 43, 60, 63, 80 23, 30, 56, 78 27, 45 23, 79 76 27, 47 30, 58 23, 78 23, 30, 34, 56, 72, 78 27, 45 22, 76 32, 64 26, 84, 87 33, 68 8

Index

S. T. H. M. C. T. M. E.V. M. L. I. B. G. T. P. N. T.S. S. M. P.G. S.L. L. K.N. K. I. J.V. J. M. J.M. E.K. K. J.D. J. A. T. A.A. M. K. I.K. J. OT. S. K. H.L. N. B.G. D.

Muhcu Munch Murphy Naddeo Nagel Nägele Nakajima Nikonova Nonaka Nyberg Ogino Orakcioglu Orfanidis Osawa Páez Paidakakos Paleologos Paolini Papadopoulos Papanikolaou Parker Parker Paterakis Paterakis Patsalas Pattisapu Pattisapu Penkowa Pérez-Fígares Persson Petritsis Pickard Pickard Piotrowicz Pirttilä Podtelezhnikov Pollay Polyzoidis Pople Praetorius Pyykkö Qvarlander Rabie Rekate Relkin Ries Rigamonti

22, 77 21, 36 33, 70 30, 54 26, 87 23, 79 23, 30, 34, 56, 72, 78 27, 47 28, 50 28, 52 23, 30, 34, 56, 72, 78 22, 77 8 27, 45 27, 47 22, 25, 26, 30, 45, 54, 75, 85 22, 74 30, 58 22, 26, 33, 66, 75, 85 22, 74 23, 79 27, 47 28, 30, 52, 55 8, 33, 68 8 18, 29 28, 50 28, 49 27, 47 21, 37 26, 84, 87 24, 25, 42, 80 24, 41 30, 58 31, 59 27, 47 8, 17, 18, 19, 24, 29, 31, 34 19, 32 30, 54 28, 49 31, 59 33, 67 33, 66 5, 8, 16, 17, 19, 20, 23, 28, 34,48 8, 18, 29 23, 79 22, 23, 26, 76, 79, 86

J. E.M. L.M. E. A. A. I. I. D.E. A. O. T. T. S. P. EA. M. M.U. M. A. P. S. M.G. T. G. G.D. I. M. P. C.A. L.V. H. D. F. A. A. C. S. S. L. H. D.J. E.G. S. G. K.J. N.

Rinne Rodriguez Rodriguez-Perez Rokas Rosen Rovlias Rowland Sack Sakas Sakellaropoulos Sakowitz Santarius Saul Savolainen Schiebel Schmidt Schmitt Schuhmann Schuhmann See Selviaridis Sgouros Shamdeen Shofuda Silverberg Silverberg Skagervik Sklavounou Smielewski Smith Soegaard Soininen Solomon Sotiriou Spanos Speil Sprung Stamatiou Stapleton Stavrinou Steiner-Milz Stone Stopa Stoquart El-sankari Stranjalis Streitberger Syrmos

31, 59 27, 47 27, 47 22, 26, 75, 85 25, 83 22, 26, 75, 85 28, 49 27, 46 30, 56 26, 84, 87 32, 65 24, 42 32, 64 31, 59 30, 58 24, 42, 21, 25, 31, 33, 36, 69, 81 21,23, 25, 26, 40, 79, 83, 87 19, 24, 29, 42 26 8, 17, 24 82, 8, 16, 18, 20, 25, 29, 30, 55 31, 59 28, 50 32, 64 27, 47 33, 68 25, 45 80, 25 28, 51 28, 49 31, 59 76, 79, 86, 22, 23, 26 25, 45 84, 87, 26 83, 21, 25, 40 27, 46 33, 71, 74, 22 33, 66 30, 56 32, 65 27, 47 27, 47 24, 41 56, 30 46, 27 74, 76, 22 91

TH ÜÜ).4%2.!4)/.!,Ý(9$2/#%0(!,53Ü7/2+3(/0 K. K. J. J. K.Q. J. A. M.S. S. K. T. M. M.R. C.D. A. I. M. A. P. S. A. V. V. A. A. B. K. J. M. L. M. R. M. L. R.A. R. B. E. C. L. M.A. J. M. R.K. L. G.F. J.T. 92

Takagi Takeda Tamangani Tamminen Tanis Tans Tarnaris Tatagiba Theodoropoulos Theodorou Tillgren Tisell Tofighi Toledo Toma Tsougos Tullberg Unterberg Uvebrant Vainikka Vakis Valadakis Varsos Venetikidis Verma Vienenkoetter Vio Virhammar Vladimirov Voidonikolas Walter Warty Watanabe Watkins Weerakkody Werrakody Wiedenhofer Wiener Wikkelso Willer Williams Williams Williams Wilson Wolfe Woodworth WU

33, 70 33, 70 33, 70 31, 59 27, 47 32, 62 33, 70 23, 26, 79, 87 22, 26, 75, 85 28, 52 31, 59 33, 39, 66 25, 83 27, 47 33, 66 28, 52 33, 68 30, 33, 58, 69 21, 37 31, 59 8 22, 74, 76 8, 18, 27 74, 22 27, 47 30, 33, 58, 69 27, 47 31, 61 39, 21 22, 33, 71, 74 24, 42 25, 83 23, 30, 56, 78 33, 66 24, 41 24, 42 22, 77 27, 46 8, 16, 18, 20, 21, 29, 39, 68 21, 38 28, 51 32, 64 8, 18, 29 28, 51 32, 63 86, 26 22, 30, 53, 77

Q. K. M. H.F. J.P. D. H.C.

Xiao Yamada Yamasaki Young Zheng Zinenko Zuo

22, 30, 53, 77 27, 45 28, 50 8, 17, 24, 31, 32, 60, 63 22, 30, 53, 77 80, 21, 23, 39 22, 30, 53, 77