Effectiveness Of Endovenous Laser Treatment

Long-term results about endovenous laser treatment of the Great Saphenous vein are still missing to date; therefore, success can be reported only with respect to immediate post-procedural ablation of the vein and with respect to recana-lization events during midterm follow-up. Other interesting questions like five-year success rates or questions about randomized prospective comparison to traditional surgery cannot be answered today. Also the questions whether endo-venous laser treatment is not associated with future neoan-giogenesis or if the pattern of future disease progression of venous disease is generally influenced, remain open at present, even if there is an interesting publication suggesting one mechanism for recanalization of veins after endovenous ablation.12

Immediate Success Rate of Endovenous Laser Treatment

Published data upon immediate closure of the Small Saphenous vein is still rare. Success rate of endovenous laser treatment in 39 Small Saphenous veins in which vein access was obtained was 100% at day one.2 Also complete occlusion of the Great Saphenous vein at day one or during week one after the procedure should be natural. However, early studies13,14 did not report a 100% success rate; it was around 97%. This was corroborated by our own early studies,415 but in our hands the problem was overcome when we started to treat saphenous veins with higher LEED values in the range between 80 to 100 joule per cm vein length. This was after understanding that the amount of energy delivered per cm vein length plays a central role for treatment success.15 With a setting of 30 watt continuous laser power (940 nm) and a continuous pullback speed of 3 mm/sec,10 a 100% occlusion rate of the treated vein segment at day one after laser treatment could be observed.

Recanalization during Midterm Follow-up

Durable occlusion of the treated saphenous vein segment is certainly a central goal of endovenous laser treatment. However, recanalization of the Great Saphenous vein can be observed and frequently it seems to be associated with low energy delivery during treatment.15 Figure 29.3 displays a so-far unpublished plot of otherwise published original data about three months follow-up of continuous laser treatment of Great Saphenous veins.15 It clearly displays that recana-lization is associated with low LEED values, and furthermore that veins with greater diameter require the delivery of more energy to stay occluded during the first three months after treatment. The line drawn in Figure 29.3 is the result of linear regression analysis of open boxes showing a slope of about 10 joule per cm GSV diameter. This indicates that

proximal GSVdfanietet [cm]

FIGURE 29.3 Plot of the linear endovenous energy density (LEED) versus the proximal diameter of the Great Saphenous vein. Dots resemble veins still occluded, open boxes resemble veins already recanalized 3 months after endovenous laser treatment (15 watt, continuous). The line is the result of linear regression analysis of the data of open boxes and is described by the formula y = 9.7x + 10.6.

a 15 mm diameter vein requires 10 joule of laser energy more per cm vein length to stay occluded at three months compared to a 5 mm diameter vein. Recent publications indicate that the administration of a LEED of 80 joule per cm vein length helps to reduce the frequency of recanalization events during short term follow-up.10,16,17

Relevant studies on short and midterm follow-up are put together in a recent systematic review.3 Unfortunately, data on midterm follow-up of at least one year after endovenous laser treatment are still rare. The largest study reporting on 121 procedures at 24 months showed an occlusion rate of 93.4%.14 Other studies reporting a 12-month follow-up demonstrate occlusion rates of 95.2% (N = 125)18 and 87.9% (N = 107).19 In our most recent experience, 12-month results were improved to above 98% occlusion rate (N = 91) after introduction of 30 watt high LEED treatment.10

Early recanalization of the Small Saphenous vein is not reported so far,2 but follow-up interval in this study of 37 followed legs was only median six months.

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