Endovenous laser ablation of varicose perforating veins with the 1470-nm diode laser using the radial fibre slim

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1 Published online on 15 November 2012 Phlebology, doi: /phleb Endovenous laser ablation of varicose perforating veins with the 1470-nm diode laser using the radial fibre slim Christof Zerweck, Eva von Hodenberg, Matthias Knittel, Thomas Zeller and Thomas Schwarz Department of Vascular Medicine, Universitäts-Herzzentrum Freiburg-Bad Krozingen, Germany Abstract Background: Endovenous Laser Ablation (EVLA) is one of the most accepted treatment options for varicose veins. The aim of this study was to investigate the efficacy and safety of the new radial fiber slim (ELVeS-radial-slim kit TM ) for the 1470 nm diode laser in perforator veins with a 1 month follow-up. Methods: Our prospective observational cohort study comprised 69 perforating veins in 55 patients. Ninety percent of all patients were in the CEAP-stage C3-C6. The radial fiber slim was used to occlude the perforating vein and the great or small saphenous vein in the same procedure. The primary efficacy endpoint of the study was ultrasonographically proven elimination of venous reflux in the perforating vein after at least one month. Secondary efficacy and further safety end points after one month were as follows: (1) sonographic exclusion of recanalization of the treated vein segments, (2) deep vein thrombosis (DVT), clinical pulmonary embolism (PE), or superficial vein thrombosis (SVT) as defined by objective testing, (3) death from any cause, (4) persistent clinical complaints such as pain and paresthesia. Results: Follow-up could be completed in all patients. In all treated perforating varicose veins, occlusion with elimination of reflux could be demonstrated immediately after the procedure. After one month 95.6% of the treated veins were still occluded (67/69). During follow-up, we did not diagnose any DVT, PE or SVT in the area related to the treated perforating vein. No patient died. One patient reported paresthesia distally of the puncture site. Conclusion: Endovenous laser treatment of varicose perforating veins with 1470 nm diode laser using the radial fiber slim is effective and safe with low recanalization rates during 1-month follow-up. Keywords: 1470 nm; laser; perforator; vein; radial-fiber-slim In western countries varicose veins are common with a prevalence of up to 20% in men and exceeding 25% in women. 1 Nowadays, a large proportion of varicose vein treatments are performed with thermal ablation methods. During recent years, Correspondence: Christof Zerweck cand. med., Universitäts-Herzzentrum Freiburg-Bad Krozingen, Department of Vascular Medicine, Südring 15, Bad Krozingen, Germany. christof.zerweck@herzzentrum.de Accepted 13 September 2012 the technique of endovenous laser ablation of varicose veins has improved continuously. Since 2010, a new slim radial fibre has been available that works with a 1470-nm diode laser (Cerelas D TM, Biolitec biomedical technology GmbH, Jena, Germany). The main purpose of the new fibre is to treat perforator veins. Previously, this procedure was only performed in some specialized centres. 2,3 This is due to the fact that the regular radial fibre needs a 6 French sheath, whereas the radial fibre slim fits a 16-gauge cannula which is more comfortable for the patient. In addition, with the same fibre it is possible to treat the great saphenous Copyright 2012 by the Royal Society of Medicine Press DOI: /phleb Phlebology 2012:1 7

2 C Zerweck et al. Endovenous laser ablation of varicose perforating vein (GSV) and the small saphenous vein (SSV) at once. Recent data could demonstrate that the 1470-nm diode laser in combination with a radial emission of the energy at the fibre tip is more effective than the common bare fibre which applies the energy with a high density at a straight direction from the tip. For this reason lower energy levels can be used. 4 The aim of the study was to gain initial data on the safety and efficacy of this procedure. Methods Patients Our prospective cohort study included 55 consecutive patients, who underwent endovenous laser treatment of incompetent varicose veins. All patients were referred to our vascular diagnostics unit by their general practitioner for symptomatic varicose veins. All patients signed informed consent prior to the procedure. The study was approved by the ethics committee of the University of Freiburg, Germany. All patients were seen by a physician specialized in venous disease. Baseline examination included history, physical examination and venous duplex sonography of the lower-extremity veins. Inclusion criteria for the study were incompetent perforating veins with sonographical proven reflux in one or multiple perforator veins. Only veins with a diameter.4 mm were included. Their diameters at the level of the fascial plane were measured. In addition, GSV, SSV or tributaries could be treated in the same session when there was pathological reflux (Figure 1). We excluded patients from endovenous laser ablation (EVLA) treatment, if the average size of the varicose vein was.2cm. Examinations and procedures Venous sonography was performed at each presentation (HDI 5000, linear array, 4 7 MHz, ATL, Bothell; Wash and zone, linear array 8 3 MHz, ZONARE, Mountain View, CA, USA) using a standardized examination protocol. 5,6 The varicose veins were examined in standing or sitting position to find out reflux, defined as a retrograde flow of.0.5-second duration in GSV or SSV. 7 Perforator veins were selected to treat, when there was oscillatory flow in combination with a diameter.4 mm (Figures 2 and 3). The procedure was started with a short rundown on the saphenous veins to determine the optimal puncture site that was marked with a permanent marker. The perforator veins were first focused in an oblique sonogram, then the ultrasonic probe was turned 908 to get a good longitudinal image of the vein. Afterwards, the longitudinal direction was marked again with a drawn pointer with intent to shorten the following puncture procedure. After cutaneous disinfection, the GSV was punctured closely to the distal insufficiency point, but avoiding a puncture site in the distal 2/3 of the lower leg for nerve injury reasons. The SSV was punctured the same way, here we avoided the distal 1/3 of the lower leg for the insertion. A 16-gauge cannula was used in all varicose veins, subsequently all additional perforator veins were punctured too. The radial fibre slim (ELVeS-radial slim kit TM, biolitec biomedical technology GmbH, Jena, Germany) was inserted in the GSV/SSV. Figure 1 Treatment modalities. GSV, great saphenous vein; SSV, small saphenous vein; sclerotherapy, foam sclerotherapy 2 Phlebology 2012:1 7

3 C Zerweck et al. Endovenous laser ablation of varicose perforating veins Figure 2 Perforator before ablation Figure 3 Perforator before ablation with reflux Then, we injected 5 ml 1% prilocainhydrocloride at the perforator area to provide a good toponarcosis. We carried on with tumescent local anaesthesia consisting of 200 ml of 2% ultracaine, 5 ml sodium carbonate, 5 ml epinephrine diluted in 500 ml cooled saline, injected along the perivenous space of the GSV/SSV under usage of ultrasound guidance. Subsequently, we started the laser procedure after placing the laser fibres tip according to the guidelines of the manufacturer with approximately 1 2 cm gap to the deep vein system. Laser energy was delivered at 8 W with the radial fibre slim. The varicose vein was treated to approximately 1 cm above the skin entry site. Linear endovenous energy density (LEED, J/cm), a surrogate marker of fluence (J/cm 2 ), was calculated as described elsewhere. 4 After finishing the saphenous vein, the fibre was introduced in the already placed cannula in the perforator. The tip of the fibre was placed ultrasonographically guided in the epifascial region above the fascial plane. After this manoeuvre the plastic cannula was removed completely, otherwise it could be molten through the applied energy. Before starting the laser treatment approximately 10 ml of cooled tumescent local anaesthetic was injected again around the laser fibre, this time just for cooling reasons. During laser ablation, the fibre was pulled back 1 3 cm until the tip of the fibre left the varicose vein. This was seen on ultrasound imaging and also could be felt by the investigators hands upon changing vibrations on the skin. The targeted applied laser energy was 60 J/cm in the GSV and SSV. In perforator veins much higher energy levels up to 200 J/cm were needed as we realized in our learning curve. With lower energy levels, in some cases the perforator could not be closed. Laser energy application was controlled, modifying the velocity up until the withdrawal of the catheter. After the procedure, venous outflow was checked immediately in the proximal deep veins by ultrasound. Persistent reflux in tributaries or below the treated vein was checked and additional treatment with foam sclerotherapy was applied if needed. The puncture site for foam sclerotherapy was at least 5 cm distant to the perforator. Postinterventional care Immediately after the procedure, prophylaxis of venous thromboembolism was started with enoxaparin 40 mg subcutaneously and prescribed for the following five days. Compression therapy with a graduated class II stocking (30 40 mmhg) was initiated immediately with the intention of wearing the stockings for 72 hours continuously, then during the day for a further three weeks. A non-steroidal antiinflammatory drug (diclofenac-sodium 75 mg 3 5 days twice daily) was prescribed for optional use. The patient was told to resume routine daily activities, but to avoid strenuous exercise for about one week. Follow-up examinations were performed one week and one month after laser therapy. They included clinical examination and venous sonography of the treated leg. Signs for superficial vein thrombosis/phlebitis were checked. The aim of the sonography was to examine the treated veins and the surrounding area for venous reflux and the treated veins for re-canalization and to exclude deep vein thrombosis (DVT) in the extremity. All patients were requested to present in our vascular unit or contact us by phone if symptoms of DVT or pulmonary embolism (PE) developed. Phlebology 2012:1 7 3

4 C Zerweck et al. Endovenous laser ablation of varicose perforating In addition, we asked about the amount of pain relief medication required after the procedure. Table 1 CEAP-stadium of all patients CEAP classification N/% Study endpoints Primary endpoint of the study was the occurrence of ecchymosis, bruising and the amount of LEED needed to close the perforator. The primary efficacy endpoint of the study was ultrasonographically proven elimination of venous reflux in a treated varicose perforating vein by laser after one month. Secondary efficacy and further safety endpoints after one month were as follows: (1) sonographically proven occlusion of the treated vein, (2) sonographic exclusion of re-canalization of the treated vein segments, (3) DVT, superficial vein thrombosis (SVT) or clinical PE as defined by objective testing, (4) death from any cause and (5) paresthesia. Statistical analysis Calculations were performed with SPSS for Windows (Version 11.5; SPSS, Chicago, IL, USA). Results Patients From May 2010 until July 2011, we treated 69 perforator veins in 55 patients with the radial fibre slim at a 1470-nm diode laser. In addition to the perforators, 38 GSVs and eight SSVs were treated with the same fibre. We treated up to four perforators in one patient. Energy was delivered intraluminally. In 39 patients, foam sclerotherapy of tributaries was performed after finishing the laser procedure with duplexsonographically proven closure of the perforator vein. Foam was injected into tributaries which were linked to treated perforators, the puncture site was located at least 5 cm distant to the laser site. In all patients one-month follow-up could be completed. Using the CEAP (clinical, aetiological, anatomical and pathological elements) classification, 90% of all patients were in the stadium C3 C6 before the procedure and among these 15% had a persistent venous ulcer. About 10% of the subjects were treated in a C2 stadium; these patients had pain or discomfort in the proximity of perforator (Table 1). Endovenous procedure The total average time of the procedure, beginning with the initial sonography until leaving the C1 0/0 C2 7/10.1 C3 17/24.6 C4 25/36.2 C5 10/14.5 C6 10/14.5 CEAP, clinical, aetiological, anatomical and pathological elements examination table, was minutes. In the GSVs mean energy levels were J, the LEED was 65 J/cm, whereas in the SSV mean delivered energy was J, the LEED was 71 J/cm. Higher-energy doses than in the GSV/SSV were used to close the perforators, the mean level was J, resulting in a LEED of 132 J/cm. Mean treatment length was cm in the GSV, cm in the SSV and cm in perforator veins. All results are given in Table 2. Efficacy outcomes The primary efficacy endpoint of our study, which was duplexsonographically proven termination of reflux in the perforator, could be reached in 94.2% (65/69) after one week, and in 95.6% (66/ 69) after one month without further therapy. Representative duplexsonography images after one week and one month are given in Figures 4 and 5. In all four veins that were patent after one week, complete occlusion was achieved. In one patient (I) no complete closure could be achieved primarily, and in two patients (III, IV) only a partial success was achieved after one week. In these patients we performed additional foam sclerotherapy. Both perforators were closed at one-month follow-up. Another perforator (II) occluded between the first and second presentation Table 2 Periprocedural data of all treated varicose veins GSV SSV Perforator vein Number mean energy J J J LEED 65 J/cm 71 J/cm 132 J/cm Length cm cm cm diameter mm mm mm tumescence ml ml ml Closure success after 1 week (%) Closure success after1 month (%) GSV, great saphenous vein; SSV, small saphenous vein; LEED, linear endovenous energy density 4 Phlebology 2012:1 7

5 C Zerweck et al. Endovenous laser ablation of varicose perforating veins Table 3 Data of four patients with initially ineffective ablation procedure Patient no. I II III IV Length (cm) Diameter (mm) Energy (J) BMI Foam sclerotherapy after 2 2 þ þ 1 week Partially thrombosed þ þ þ þ Shrinkage þ 2 þ 2 Closure 1 week Closure 1 month 2 þ þ þ BMI, body mass index Figure 4 Perforator one week after ablation without any additional therapy. The data of these four perforating veins are shown in Table 3. In summary, all but one perforator could be successfully closed with a combination therapy of laser ablation and foam sclerotherapy. Safety outcomes At one-week follow-up, we diagnosed two muscle vein thromboses. In both cases, the intramuscular part of the perforator vein was thrombosed by few centimetres. These patients were treated with fulldose anticoagulation therapy for 10 days, both showed regression of the thrombus after two weeks. No DVT occurred and no SVT due to the laser ablation was diagnosed in the proximity of the treated perforating veins. No patient died or had a pulmonary embolization documented. One patient reported paresthesia in a 10 cm 3cm area distant to the ablated perforator in the medial distal lower leg. Figure 5 Perforator one month after ablation Discussion Our results show that treatment of incompetent perforating veins with the radial fibre slim and a 1470-nm diode laser is effective and safe. Compared with other 1470-nm diode laser ablation studies 4 of the GSV, we could reach similar success rates regarding the GSV with the radial fibre slim. When focusing on the closure rate of perforators after ablation, initially not all veins could be successfully treated. This might be due to the very short ablation distance in comparison with an ablation in the saphenous veins. It is conceivable that blood flow on both ends of the short intra-perforator thrombus can lead more easily to re-canalization than in longer distances. The venous high blood pressure on the muscle side towards the closed perforator while standing and walking may be another mechanism for re-canalization. In addition, the mechanical destruction of the thrombus when walking might cause an unstable occlusion. Remarkably, in the three perforators with unsuccessful treatment, the body mass index was elevated, which correlates with a Brazilian laser ablation study of the GSV 8 showing similar results with higher LEED needed in obese patients. On the other hand, other data showed no influence of obesity on LEED needed for successful closure of the varicose vein. 9 Studies 3 and case reports 2,9 published so far on laser ablation of perforators using other laser devices could also show proof of the concept. However, in some cases closure success rates were lower, although using higher LEED levels in smaller vein diameters than those shown in Table 4. It could be demonstrated that the amount of energy applied in the vein is an independent predictor of vessel occlusion. 10,11 A recently published study of ours, 4 also performed with 1470 nm diode laser device and a radial fibre proved 55 J/cm LEED to Phlebology 2012:1 7 5

6 C Zerweck et al. Endovenous laser ablation of varicose perforating Table 4 Comparison with other studies 1470 nm Zerweck 1320 nm Proebstle 940 nm Proebstle 940 nm Ozkan Perforators Diameter (mm) (1.1 8) 3.3 (1.1 8) Energy delivery (W) Continuous Pulsed Pulsed Pulsed LEED (J/cm) Mean energy (J) (90 625) 250 ( )? Closure success 1 week 1 day 1 day? 94.2% 100% 100% Closure success 1 month 3 months 3 months 1 month 95.6% Shrinkage, no data Shrinkage, no data 83.3% LEED, linear endovenous energy density be effective in closure. Our data of the radial fibre slim reports in the GSV 65 J/cm and in the SSV 71 J/cm to be effective. This higher energy amount is probably due to the smaller laser light-emitting area on the thinner fibre tip compared to the common radial fibre. Supporting this hypothesis, we saw more carbonization on the radial fibre slim than on the common radial fibre. When comparing LEED levels in the GSV/SSV and in perforators, almost twice as high-energy doses were used for successful ablation of perforators. This is highly likely due to the short distance in perforators needed for a palpable shrinkage during the ablation procedure. Furthermore, a former study had reported lower-energy doses to be inferior in ablation success. 3 Limitations of the study In this study we present a short-term follow-up of one month. During this time period re-canalization of treated varicose veins which were closed after one week was not seen. Thus, the long-term success as compared with other treatment options, such as surgery remains to be assessed by future studies. Conclusion Our results show that treatment of incompetent perforating veins with the radial fibre slim and a 1470-nm diode laser with additional foam sclerotherapy of tributaries if needed is effective and safe in the short-term follow-up. Compared with the common radial fibre no 6-French sheath is needed and multiple vessels including perforators can be treated in one session with only one fibre which reduces costs per patient. EVLA is a further optional treatment for perforators in patients with ulcer or coexistent peripheral arterial obstructive disease. Author contributions: Conception and design: CZ; analysis and interpretation: CZ, EVH and TS; data collection: CZ, EVH and TS; writing the article: CZ; critical revision of the article: CZ, TS, EVH, FJN and TZ; final approval of the article: TS, TZ and FJN; statistical analysis: CZ and overall responsibility: CZ. Competition of interest: None. References 1 Maurins U, Hoffmann BH, Lösch C, Jöckel KH, Rabe E, Pannier F. Distribution and prevalence of reflux in the superficial and deep venous system - results from the Bonn vein study. J Vasc Surg 2008;Sep;48(3): Epub 2008 Jun pubmed/ Ozkan U. Endovenous laser ablation of incompetent perforator veins: a new technique in treatment of chronic venous disease. Cardiovasc Intervent Radiol 2009; 32: Proebstle TM, Herdemann S. Early results and feasibility of incompetent perforator vein ablation by endovenous laser treatment. Dermatol Surg 2007;33: Schwarz T, von Hodenberg E, Furtwängler C, Rastan A, Zeller T, Neumann FJ. Endovenous laser ablation of varicose veins with the 1470-nm diode laser. J Vasc Surg 2010;51: Schwarz T, Schmidt B, Schellong SM. Inter observer agreement of complete compression ultrasound for clinically suspected deep vein thrombosis. Clin and Appl Thromb Hemost 2002;8: Schellong SM, Schwarz T, Halbritter K, et al. Complete compression ultrasonography of the leg veins as a single test for the diagnosis of deep vein thrombosis. Thromb Haemost 2003;89: Jeanneret C, Labs KH, Aschwanden M, Bollinger A, Hoffmann U, Jäger K. Physiological reflux and venous diameter change in the proximal lower limb veins during a standardised Valsalva manoeuvre. Eur J Vasc Endovasc Surg 1999;17: Phlebology 2012:1 7

7 C Zerweck et al. Endovenous laser ablation of varicose perforating veins 8 Narvaes, Luciane B. Endovenous Laser Ablation: Obesity and delivered LEED. Presented on the International Congress of the Union Internationale de Phlebologie European Chapter Meeting 2011; Uchino IJ. Endovenous laser closure of the perforating vein of the leg. Phlebology 2007;33: Proebstle TM, Krummenauer E, Gul D, Knop J. Nonocclusion and early reopening of the great saphenous vein after endovenous laser treatment is fluence dependent. Dermatol Surg 2004;30: Theivacumar NS, Dellagrammaticas D, Beale RJ, Mavor AI, Gough MJ. Factors influencing the effectiveness of endovenous laser ablation (EVLA) in the treatment of great saphenous vein reflux. Eur J Vasc Endovasc Surg 2008;35: Phlebology 2012:1 7 7