MAY - JUNE 2014
Visual disturbance following sclerotherapy for varicose veins, reticular veins and telangiectasias: a systematic literature review PAGE 6
Thrombus formation using endovenous lasers: an in vitro experiment PAGE 9
ACP 2014
28TH ANNUAL CONGRESS
November 6 – 9, 2014 | JW Marriott Desert Ridge Resort | Phoenix, AZ Join your colleagues at the American College of Phlebology’s 28TH Annual Congress for the latest techniques and education in the treatment of venous and lymphatic disease. The accessible scientific program addresses the full spectrum of deep and superficial vein care in didactic, interactive, debate and hands-on demonstration sessions, providing practitioners with:
+ Opportunities to improve patient care at all levels of skill from foundational through advanced + Presentations and exhibitors of leading research, technology and trends in the field of vein care + Hands-on workshops and demonstrations with renowned experts from all over the world
Register Today For more information and to register, visit the ACP Congress website at:
acpcongress.org www.phlebology.org | 510.346.6800
advancing vein care
From the Editor-in-Chief Nick Morrison, MD, FACS, FACPh, RPhS
may-jun ‘14
contents
Visual disturbance following sclerotherapy for varicose veins, reticular veins and telangiectasias: a systematic literature review Contributing Editor/Reviewer: Kenneth Myers MD
5
Associate Editor: Eric Mowatt-Larssen, MD
6 Compression Stockings To Prevent PostThrombotic Syndrome: A Randomized PlaceboControlled Trial
Thrombus formation using endovenous lasers: an in vitro experiment Contributing Editor/Reviewer: Thomas M. Proebstle, MD Associate Editor: Mitchel Goldman, MD, FACPh
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Contributing Editor/Reviewer: Joseph A. Caprini, MD, MS, FACS, RVT; Antonios P. Gasparis, MD, FACS; Nicos Labropoulos, MD; Hugo Partsch, MD, FACPh, Thomas W. Wakefield, MD Associate Editor: Sherry Scovell, MD
Role of injection pressure, flow and sclerosant viscosity in causing cutaneous ulceration during sclerotherapy Contributing Editor/Reviewer: Malay Patel MD Associate Editor: Diana Neuhardt, RVT, RPhS
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11
disclosure of interests
Name
ACP Role
Date Submitted
Disclosure
Stephanie Dentoni, MD
Recruitment & Retention(Chair), Leadership Development
9/8/13
Nothing to Disclose
Mark Forrestal, MD, FACPh
ACP BOD(President-Elect) Advocacy(Chair), Nominating, Finance, Exhibitor Advisory, Phlebology Forum,
9/8/13
Cooltouch Lasers: Speaker, Trainer
Mitchel Goldman, MD, FACPh
Phlebology Forum
9/8/13
Merz Aesthetics/Kreussler: Consultant/Research; New Star Lasers: Consultant
Jean-Jerome Guex, MD, FACPh
ACP BOD, Advocacy Standing, AMA HOD Task Force, International Affairs, VeinLine, Leadership Development, Annual Congress Planning
9/8/13
Servier International: Speaker/Consultant; Thusane: Scientific Committee Member; Vascular Insights: Scientific Committee Member
Lowell Kabnick, MD, FACS, FACPh
Phlebology Forum
9/8/13
Angiodynamics: Consultant, Shareholder, Patent; Veniti, Scientific Advisory Board; BTG: Consultant
Neil Khilnani, MD, FACPh
ACP BOD(Secretary), Member Engagement(Chair), CME Standing, CME, CME Workgorup 1,
9/8/13
Sapheon: Data Safety Board Member
Ted King, MD, FAAFP, FACPh
ACP BOD, Leadership Development, Annual Congress Planning, Public Education
9/8/13
BTG International: Consultant/Advisory Board Member/Principal Investigator; Veniti: Advisory Board/ Consultant; Sapheon: Investigator
Mark Meissner, MD
ACP BOD, Eductation, CME, Fellowship Training(Chair)
9/8/13
Nothing to Disclose
Nick Morrison, MD, FACS, FACPh
ACP Foundation (Chair), ACP Ethics and Industrial Advisory Committees, Phlebology Forum (Editor-in-Chief)
2/24/14
medi: Educational Grant; Merz: Consultant/Speakers Bureau; Sapheon: Principle Investigator; VeinX: Scientific Advisory Board
Eric Mowatt-Larssen, MD
ACP Leadership Development CME Workgroup 2 & 3
6/25/12
BTG International, Inc.: Consultant
Diana Neuhardt, RVT, RPhS
ACP BOD, Member Engagement, Education, VeinLine, Phlebology Forum, Leadership Development, Public Education(Chair), CME-Workgroup 2
6/15/12
Nothing to Disclose
9/8/13
Nothing to Disclose
Pauline RaymondMartimbeau, MD, FACPh
ACP Foundation BOD
From the
Editor-in-Chief Dear Readers
The phlebologic literature seems to be exploding with ever higher quality reports in a number of journals. In this issue of Phlebology Forum we have a very interesting mix of articles with outstanding commentary by a panel of experts in the field with some very practical insight into things as phlebologists we deal with on a daily basis, including the review on the important SOX trial which has really caused all of us to pause and reevaluate the use of compression hose in the treatment of patients with DVT.
We wish you all a warm and pleasant summer and look forward to seeing you in November at the ACP Annual Congress. Nick Morrison, MD Editor-in-Chief Phlebology Forum
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Visual disturbance following sclerotherapy for varicose veins, reticular veins and telangiectasias: a syste mati c l iteratu re review Authors: Gillet JL, Donnet A, Lausecker M et al. Phlebology 2010;25:261-6 Contributing Editor/Reviewer: Kenneth Myers MD Associate Editor : Eric Mowatt-Larssen, MD
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Synopsis The authors reviewed 25 reports that were considered suitable to study the prevalence of visual disturbances (VD) following sclerotherapy for varicose veins, reticular veins and telangiectasias including four randomised trials. Only three studies were for treatment of reticular veins and telangiectasias alone. From 4948 results that could be analysed, transient VD occurred in between 0.09% and 2%. The authors indicate their frustration that it was frequently difficult to determine whether this referred to patients or treatment sessions. The great variation in treatment techniques relating to choice of polidocanol or sodium tetradecyl sulphate, sclerosant concentrations (0.25 – 3%), and liquid/ gas ratio in foam made it difficult to find significant differences between techniques. Nor could they assess whether there were any patient characteristics that influenced the risk. They concluded that bubble embolism was unlikely to cause VD and favour a systemic response resulting from endothelial cell lysis releasing agents such as endothelin as the likely cause.
They concluded that bubble embolism was unlikely to cause visual disturbance
COMMENTARY This article provides a great service by focusing attention on a complication that can be a source of considerable concern to patients though perhaps less to the treating doctors. The authors undoubtedly appreciate that the study teases the reader by its inability to link the risk of VD complicating treatment with the size of the veins treated, treatment technique or patient characteristics.
There were a few positives that were observed. Symptoms of blurred or double vision or scotomas were shown in one study to be unilateral in about one-third and bilateral in about two-thirds.1 Foam sclerotherapy was used in 19 of the 25 studies and combined foam and liquid in four so that there were only two studies for liquid sclerotherapy alone, while two randomised studies comparing liquid and foam using polidocanol reported no VD events in either group.2 3 The authors refer to studies by Morrison and colleagues that showed that VD was much more likely to occur with foam volumes greater than about 15ml and with foam prepared with air than with a CO2 alone or a CO2/O2 mixture.4
Otherwise, numbers were insufficient to draw conclusions as to whether or not the risk was different according to the use of either sclerosant, foam versus liquid, methods to prepare foam relating to liquid/gas ratio, sclerosant concentration or the volumes of foam injected. Nor did the study provide analysis of patient characteristics such as pre-existing migraine (although this is extensively analysed in Discussion), presence of a patent foramen ovale or any
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other patient characteristics. This is not a criticism of the study which repeatedly points out the absence of such information in the reported series.
The authors refer to poor reporting relating to whether patients or treatment sessions were analysed and this seems to be critical for future studies. Given that so many of our patients require multiple treatment sessions, this should be capable of analysis to test our anecdotal impression that there are patients who repeatedly show the symptoms, frequently those with a known history of migraine.
However, one would be pessimistic as to the prospects for relating risk to the above variables by appropriate large randomised trials in the future. Foam sclerotherapy now so dominates treatment that it would seem impossible to determine whether or not liquid sclerotherapy carries less risk. In addition, most practitioners find it so much easier to use air than a CO2 preparation that large studies for this variable would be difficult. There are so many variations in liquid/gas preparation that this is impossible to standardise. Finally, the type of sclerosant used may be important although it would not be expected to warrant a large randomised study. Furthermore, the prevalence is so low that it would require huge observational studies using different techniques in a wide range of patients with veins of varying sizes to be able to obtain significant results by multivariate analysis.
In spite of the authors’ opinions, possible mechanisms remain uncertain. Can unilateral VD be due to a systemic cause? Is the effect mediated through the cerebral cortex or the eye itself? Can bubbles to the brain be totally excluded as a possible cause – the authors do comment that the phenomenon does not appear to have been reported prior to the introduction of foam sclerotherapy. It might be of interest to perform larger studies to determine whether there is any correlation between VD and bubbles in the middle cerebral artery observed with transcranial Doppler.
The authors correctly conclude that more research is needed. But can we anticipate that large randomised trials sifting out each of the variables will be performed given that the symptom is usually of no great concern to treating doctors. One hopes so, for the uncommon transient reversible event of VD might just hint at a possible risk of other irreversible cerebral events. 1234
REFERENCES 1 Gillet JL, Donnet A, Lausecker M et al. Pathophysiology of visual disturbances occurring after foam sclerotherapy. Phlebology 2010;25:261-6. 2 Alos J, Carreno P, Lopez JA et al. Efficacy and safety of sclerotherapy using polidocinol foam : a controlled clinical trial. Eur J Vasc Endovasc Surg 2006;33:101-7. 3 Ouvry P, Allaert FA, Desnos P, Hamel-Desmos C. Efficacy of polidocinol foam vs liquid in sclerotherapy of the great saphenous vein: a multicentre randomised controlled trial with a 2-year follow-up. Eur J Vasc Endovasc Surg2008;36:366-70. 4 Morrison N, Neuhardt DL, Rogers CR et al. Comparison of side effects using air and carbon dioxide foam for endovenous chemical ablation. J Vasc Surg 2008;47:830-6.
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Thrombus formation using endovenous lasers: an in vitro experiment Authors: Hennings T1, Hennings D, Lindsay C. Phlebology. 2014;29(3):1-8. doi: 10.1177/0268355512473921. Epub 2013 May 6. Contributing Editor/Reviewer: Thomas M. Proebstle, MD Associate Editor: Mitchel Goldman, MD, FACPh
Abstract In their in-vitro experiments Hennings et al. investigated the clot formation at the laser fiber tip using lasers generally suitable for endovenous ablation. They tested continuous wave diode and microsecond pulsed solid-state nearinfrared lasers at wavelengths between 810 and 2100 nm with different types of laser-fibers in a porcine blood set-up. Currently the cw-diode lasers 810, 940, 980 and 1470 nm and the microsecond pulsed solid-state 1320 nm laser are in widespread clinical use.
The authors convincingly demonstrated that high peak power is able to prevent in-vitro clot formation at the fiber tip. Using an average power output of 7 Watts, microsecond pulsed solid state lasers with peak powers up to 3500 Watts (1320 nm, 100 Âľsec pulse duration, 20 Hz pulse frequency) clearly proved to be superior compared to cw-diode lasers operating at a maximum power of 7 Watts. Also reduction of laser fiber diameter caused less generation of coagulum at the fiber tip due to an increased power density at the fiber-tip aperture. However, apart from differences in the time course of laser energy generation (cw-diode versus microsecond pulsed)
microsecond pulsed
laser wavelength was not able to affect clot formation at the
solid-state lasers
laser fiber tip. Moreover, fiber-tip design did not influence clot formation either.
with their high peak power were able
In conclusion, microsecond pulsed solid-state lasers with their high peak power were able to prevent in-vitro clot formation in contrast to cw-diode laser systems and may transfer this advantage into clinical practice.
to prevent in-vitro clot formation in contrast to cwdiode laser systems
Commentary The optimal laser, its wavelengths, power settings, energy dosing, method of fiber pullback and type of fiber tip have been a matter of discussion in endovenous ablation since its introduction. To date there is general agreement that continuous fiber pullback is preferable over stepwise fiber pullback and that sufficient energy dosing in terms of LEED or EFE1 is key to successful and durable occlusion of the treated vein. There is much less consent about the right laser wavelength, the right fiber tip, or about the issue whether solid state pulsed laser systems outperform the technically much less complicated cw-diode machines.
1 Proebstle TM, Krummenauer F, GĂźl D, Knop J. Nonocclusion and early reopening of the great saphenous vein after endovenous laser treatment is fluence dependent. Dermatol Surg. 2004;30:174-8.
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Initially, in the early days of endovenous laser ablation, almost exclusively cw-diode lasers emitting the hemoglobinabsorbed wavelengths 810, 940 or 980 nm were used. However, clinical studies were not able to demonstrate significant differences with respect to efficacy or side effects of one wavelength over the other.2
Somewhat later, reports indicated that the water-absorbed 1320 nm Nd:YAG laser avoided vein wall perforations while the cw-diode systems widely used at that time were truly cutting the vein, allowing the laser energy to escape into the perivenous tissue.3 Additionally, a preliminary clinical study presented data indicating less pain after 1320 nm treatment compared to a 940 nm diode laser.4 Soon thereafter other developments included water-absorbed diode lasers with an emitted wavelength of 1470 nm entered the market and new fiber tip designs were marketed aiming to prevent contact of the laser emitting part of the fiber with the vein wall; and power density reduction of the emitted beam by a radial design. Some subsequent studies suggested that the new 1470 nm wavelength - at least in conjunction with a radial fiber tip design - reduced clinical side effects by avoiding vein wall perforations. However, reported data are inconsistent upon this issue. Unfortunately, no further comparative studies included the solid state microsecond pulsed 1320 nm laser system and even a recent in-vitro study did not address the 1320 Nd:YAG machine comparing the available laser technology in its whole against each other with respect to the peak and time course and peak of extraluminal temperatures.5
The 1320 nm Nd:YAG laser, like other microsecond pulsed systems, is able to deliver a peak power of up to 5 kWatts which corresponds to a peak power density of more than one MWatt/cm² if a fiber aperture of a diameter of 500 ¾m is given. Such power densities are in the photo-accoustic range and therefore reliably remove initial clot and debris from the fiber tip surface. Not much attention has been directed to this major technical difference between the solid state and the cw-diode lasers.
In this situation the paper of Hennings et al is greatly appreciated, addressing the question how clot formation at the fiber tip could be minimized by choosing appropriate laser parameters and laser machines.
It sets the field for future more detailed investigation of treatment protocols which potentially would minimize endovenous clot formation and furthermore reduce risks and side effects of an already established and widespread technology.
2
Kabnick LS. Outcome of different endovenous laser wavelengths for great saphenous vein ablation. J Vasc Surg. 2006; 43:88-93.
3 Goldman MP, Mauricio M, Rao J. Intravascular 1320-nm laser closure of the great saphenous vein: a 6- to 12-month follow-up study. Dermatol Surg. 2004;30:1380-5. 4 Proebstle TM, Moehler T, GĂźl D, Herdemann S. Endovenous treatment of the great saphenous vein using a 1,320 nm Nd:YAG laser causes fewer side effects than using a 940 nm diode laser. Dermatol Surg 2005;31:1678-83; discussion 1683-4. 5 Malskat WS1, Stokbroekx MA, van der Geld CW, Nijsten TE, van den Bos RR. Temperature profiles of 980- and 1,470-nm endovenous laser ablation, endovenous radiofrequency ablation and endovenous steam ablation. Lasers Med Sci. 2014; 29:423-9.
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Compression Stockings To Prevent Post-Thrombotic Syndrome: A Randomized Placebo-Controlled Trial Author: Kahn SR, Shapiro S, Wells PS, et al. The Lancet 2014;383:880-8. Contributing Editor/Reviewer: Joseph A. Caprini, MD, MS, FACS, RVT; Antonios P. Gasparis, MD, FACS; Nicos Labropoulos, MD; Hugo Partsch, MD, FACPh, Thomas W. Wakefield, MD Associate Editor: Sherry Scovell MD
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ABSTRACT The SOX trial is a multicenter, placebo-controlled study that compared active versus placebo elastic compression stockings (ECS), used for two years, to determine if ECS can prevent the development of post-thrombotic syndrome (PTS) after proximal deep venous thrombosis (DVT).1 The results of this study are in contrast with those from two randomized trials that suggested that wearing ECS for 2 years after a proximal DVT can decrease the development of PTS by approximately 50%.2,3 Between 2004 and 2010, 806 patients in 24 centers in Canada and the USA were enrolled. The DVT had to be located from the popliteal vein up. Patients were
After reviewing this manuscript we would
randomized if ultrasound confirmed DVT in the last two
conclude that this
weeks, then stockings were sent by mail, and were replaced
study contradicts
every 6 months. It may be assumed that treatment started considerably later. No compression is reported in the acute stage. Patients received either active 30-40mmHg graduated ECS or placebo-stocking with an identical appearance but less than 5mmHg compression at the ankle, pressures supplied by
findings from multiple smaller trials as well as two systemic reviews
the producers. Treatment allocation was masked from the patients. The period of treatment was 2 years, and follow-up visits occurred at 1, 6, 12, 18, and 24 months. The primary endpoint was the cumulative incidence of PTS (from 6 to 24 months follow-up), diagnosed by Ginsberg’s criteria. Secondary endpoints were cumulative incidence and severity of PTS by Villalta criteria, the presence of leg ulcers, objectively confirmed recurrent VTE, death, adverse events, venous reflux at the level of the popliteal vein (at 12 months), and quality of life.
The cumulative incidence of PTS was 14.2% in the active ECS group, and 12.7% in the placebo ECS group (not different) using the Ginsberg criteria. There were no differences in the cumulative incidence of PTS defined with Villalta criteria, distribution of PTS severity category, and the rate of ipsilateral leg ulcer. Rates of recurrent VTE, ipsilateral DVT, and death were similar between groups. Venous reflux at 12 months was also similar. There were no differences in generic and disease-specific quality of life results. Use of study stockings at each visit was similar between groups. Results were similar in prespecified per-protocol analysis of patients who reported ‘frequent’ use of stockings (3-6 days per week). The interpretation was that ECS did not prevent PTS after a first proximal DVT. 1
Kahn SR, Shapiro S, Wells PS, et al. Compression stockings to prevent post-thrombotic syndrome: a randomised placebo-controlled trial. The Lancet 2014;383:880-8.
2 Brandjes DP, Buller HR, Heijboer H, et al. Randomised trial of effect of compression stockings in patients with symptomatic proximal-vein thrombosis. Lancet 1997;349:759-62. 3 Prandoni P, Lensing AW, Prins MH, et al. Below-knee elastic compression stockings to prevent the post-thrombotic syndrome: a randomized, controlled trial. Annals of Internal Medicine 2004;141:249-56.
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COMMENTARY After reviewing this manuscript we would conclude that this study contradicts findings from multiple smaller trials as well as 2 systemic reviews.2-4 In the current study, the patients did not keep a diary but relied on their memory for calculating the amount of time of stocking usage. This is a flaw in not only the current study but a potential confounder in all studies of compression. This type of documentation without a diary may be sketchy. Our clinical
experience would indicate that patients exaggerate their use of stockings. Since only half of the patients wore their stockings more than 3 times per week by their own admission, one might say that this represents a significant concern in the study. The patients received no instructions on donning and doffing these stockings as well as someone observing how well they were able to perform the task. However, less than half of the patients were able to tell if they had a strong or mild stocking. The single largest complaint we see in practice involves patients reporting difficulties in applying and removing the stockings. Approximately one third of these individuals with complaints will have sufficient difficulties that will prevent their consistent and long-term use. Older heavier patients as well as those with arthritic joints are examples that require alternate methods of compression. We realize that in a blinded randomized clinical trial conducting all of the above investigations would result in unblinding of the trial. Unfortunately all of the above problems also confound study results. Apparently simple questions about problems applying or removing stockings were not asked. We believe that in order to optimize the management of patients with DVT, wearing ECS should start on the day of diagnosis and patients should be mobilized as soon as possible. The application of ECS and walking has shown to reduce pain and swelling after one week.5 Patients can recognize the fast relief from the symptoms and be encouraged to continue to use ECS.
The Ginsberg criteria and the Villalta score may not accurately characterize edema since they rely on the
discretion of the observer. Lattimer found no correlation within the Villalta score between patient symptoms and clinical signs.6 Correlations between Villalta and the venous clinical severity score were improved when the Villalta patient-reported part was excluded. This means that patients with severe symptoms may have minimal signs and vice versa. Latimer also demonstrated that there was no correlation between the patient portion of the Villalta score and the venous segmental disease score. The astonishing incidence of leg ulcers in both groups, especially early is surprising. The similar incidence in the occurrence of ulcers may reflect the lack of effectiveness of the therapeutic group based on poor compliance and/or delayed start of compression.
4
Kolbach D, MWSandbrink, Hamulyak K, Neumann H, Prins M. Non-pharmaceutical measures for prevention of post-thrombotic syndrome. Cochrane Database Syst Rev 2004;(1):CD004174 2004.
5 Partsch H, Bl채ttler W. Compression and walking versus bed rest in the treatment of proximal deep venous thrombosis with low molecular weight heparin. J Vasc Surg. 2000 ;32:861-9. 6 Lattimer CR, Kalodiki E, Azzam M, Geroulakos G. Validation of the Villalta scale in assessing post-thrombotic syndrome using clinical, duplex, and hemodynamic comparators. Journal of Vascular Surgery: Venous and Lymphatic Disorders 2014;2:8-14.
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CONCLUSION In conclusion this study was a valiant effort to answer a very important clinical question using a blinded randomized trial design. We applaud the authors for their efforts to control as many variables as possible. Now that it has been published in a prominent journal the findings will likely be incorporated into the next iteration of guidelines. We hope these editorial comments will also be discussed. However, it must be kept in perspective that there is data still supporting stocking use for prevention of PTS, and the overall risk profile of stocking usage is low. There remains potential benefits for appropriately fitted stockings following acute DVT. They must be worn most of the time to achieve benefits, especially when swelling is present. Until a study is done with high compliance it would be a shame for reimbursement for stockings to be denied. Before we change our practice, we await additional confirmation of the current findings.
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Role of injection pressure, flow and sclerosant viscosity in causing cutaneous ulceration during sclerotherapy Author: R K Miyake, et al Phlebology. 2012 Dec;27(8):383-9. doi: 10.1258/phleb.2011.011076. Epub 2012 Feb 8. Contributing Editor/Reviewer: Malay Patel, MD Associate Editor: Diana Neuhardt, RVT, RPhS
COMMENTARY Liquid sclerosants were in use since long ago, with varying degrees of success for treating varicose veins of the legs. Some complications occurred and the troublesome complication of cutaneous ulceration was thought to be due to extravasation of the sclerosant in the perivenous and subcutaneous tissue. A report published in 1968 based on animal experiments supported the theory of extravasation of the sclerosants as a causative factor for cutaneous ulcerations.1 Also while treating telangiectasias, cutaneous ulceration was observed and this widely held belief that extravasation or perivenous injection of the sclerosant was responsible for this complication, became the dominant theory. In 1972, Miyake published his, venous–capillary reflux theory in a non-English journal. He tried to prove the theory that
With the advent of
cutaneous ulceration was not caused by the extravasation
foam sclerosants and
or perivenous injection of liquid sclerosant as previously believed, but was caused by reflux of the liquid sclerosant into the feeding arterioles.2 The English speaking world remained
injections done under ultrasound guidance,
oblivious of this work.
the already low
Years later, extensive tissue necrosis following intravenous
incidence of cutaneous
sclerosant injection, in 5 patients, was reported by Bergan et al.3 They too proposed the theory of distribution of the sclerosant
necrosis, dropped lower.
into the arterial arborization.
This complication is
Studies done with liquid sclerosants did report a small
now considered rare.
incidence of cutaneous necrosis while treating telangiectasis. A large Australian study done on 34,878 legs reported 60 (0.17%) injection ulcers.4 Overall the complication rate of cutaneous necrosis is small, whether for telangiectasis or varicose veins, but, it is best prevented. Miyake (son of original author) et al. in a recent paper (in English), ‘Role of injection pressure, flow and sclerosant viscosity in causing cutaneous ulceration during sclerotherapy’ have tried to substantiate the venous–capillary reflux theory further, by emphasis on injection pressure and viscosity of liquid sclerosants. Traverse of injected fluid relies upon the injection pressure and viscosity. Commonly used sclerosants (foam or liquid) are
1 Blenkinsopp WK. Comparison of tetradecyl sulphate of sodium with other sclerosants in rats. Br J Exp Pathol. 1968 April;49(2):197–201. 2 Miyake H. Necroses cutâneas provocadas por injeções de substâncias esclerosantes utilizadas no tratamento de microvarizes e telangiectasias. Tese de Doutoramento. Faculdade de Medicina da Universidade de São Paulo, 1972 3 Bergan JJ, Weiss RA, Goldman MP. Extensive tissue necrosis following high-concentration sclerotherapy for varicose veins. Dermatol Surg. 2000 Jun;26(6):535-41. 4 Malouf GM, Conrad P, Stacey MC. The Australian Polidocanol Study – October 1991 to December 1994. Scope on Phlebology and Lymphology. 1996; 3:8-11.
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injected with 2cc-5cc syringes. Smaller diameter (capacity) syringes generate higher pressures. In a resting syringe the initial break-away force is overcome by thumb pressure and the plunger starts moving through the barrel. Injection is maintained by the glide-force that overcomes the friction of the plunger within the barrel. The pressures at the tip of a needle attached to the syringe can easily exceed the systolic arterial pressure and it is not surprising that sclerosant (foam or liquid) can travel retrograde or circuitously, into arterioles. A study of simulated injections carried out showed that even experienced injectors generated variations in flow rates due to difficulty produced by ‘syringe feel’ and maintaining continuous pressure.5 6 7 Thus not only are high pressures generated at the tips of the injection needle but bursts of fluid expulsion also occur. This makes it very important to increase pressure gradually, inject minute quantities as steadily as possible and inject only those areas under the field of vision preferably enhanced by ultrasound. This will minimize the sclerosant (foam or liquid) traversing beyond the treatment area. With the advent of foam sclerosants8 9 and injections done under ultrasound guidance, the already low incidence of cutaneous necrosis, dropped lower. This complication is now considered rare.10 11 Animal experiments show that injection of up to 0.5ml of 1% foamed sclerosant, made in the subcutaneous tissue is well tolerated.12 Miyake et al. in their paper further propose that solutions with higher viscosity have a lower propensity to produce cutaneous complications because the more viscous solution traverses shorter distances with the same plunger pressure. Nevertheless cutaneous ulceration after injection of telangiectasias still occurs and and creates a problem larger than the one it set out to take care of and possible medico-legal trouble. So to decrease the incidence of cutaneous necrosis..... Anyone treating telangiectasis should use low concentration (<1%) foamed sclerosants with minimal plunger pressures preferably, with 5 ml. syringes. Additionally use of tumescence before, during or immediately after the injection of the slcerosant (foam or liquid) can help contain it and may decrease the incidence of cutaneous necrosis to make it a very rare occurrence.13 5 Hayward WA, Haseler LJ, Kettwich LG, et al. Pressure generated by syringes: Implications for hydrodissection and injection of dense connective tissue lesions. Scand J Rheumatol;40(5):379-82 6 Izafalia M, Sixou J-L. Administration of anesthetics using metal syringes. An ex vivo study. Anesth Prog. 2011 Summer;58(2):61-65 7 Claudio R, Hadzic A, Shih H et al. Injection pressures by anesthesiologists during simulated peripheral nerve block. Reg Anesth Pain Med, 2004;29:20-205 8 Green AR, Morgan BD. Sclerotherapy for venous flare. Br J Plast Surg. 1985;38:241–242 9
Tessari L. Nouvelle technique d’obtention de la sclero- mousse. Phlebologie 2000;53:129
10 Coleridge-Smith P. Foam and liquid sclerotherapy for varicose veins. Phlebology 2009;24 Suppl 1:62–72 11 Cavezzi A, Parsi K. Complications of foam sclerotherapy. Phlebology 2012 Mar;27 Suppl 1:46-51 12 Schuller-Petrovi S, Pavlovi, MD, Neuhold N, Brunner F, Wölkart G. Subcutaneous injection of liquid and foamed polidocanol: extravasation is not responsible for skin necrosis during reticular and spider vein sclerotherapy. J Eur Acad Dermatol Venereol. 2011 Aug;25(8):983-6 13 Ramelet AA. Sclerotherapy in tumescent anesthesia of reticular veins and telangiectasias. Dermatol Surg 2012 May:38(5):748-51
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