Nonocclusion and early reopening of the great saphenous vein after endovenous laser treatment is fluence dependent.

BACKGROUND: Parameters influencing failure and recanalization rates of endovenous laser treatment (ELT) of the great saphenous vein (GSV) are still to be determined.

OBJECTIVE: To evaluate treatment-related parameters of ELT with respect to early failure of occlusion or recanalization of GSVs.

METHODS: A series of 77 consecutive patients received ELT of 106 GSVs with continuous pullback of the laser fiber. Duplex examination was performed at 1 day, 4 weeks, and 3 months after the procedure. Clinical patient and vessel characteristics as well as technical parameters of the ELT procedure were evaluated via multiple logistic regression analysis.

RESULTS: A median vein length of 60 cm (range of 18 to 90) was treated with a median pullback velocity of 0.6 cm/sec (range of 0.4 to 1.3), resulting in a median energy delivery of 23.4 J/cm (range of 11.8 to 35.5) and a median laser fluence of 11.8 J/cm2 (range of 2.8 to 37.3). At day 1 after ELT, 6 GSVs (6%) were not occluded. At 1 and 3 months after ELT, 9 GSVs (9%) and 11 GSVs (10%), respectively, were found open by color duplex examination. Risk factors for nonocclusion 3 months after ELT, by univariate analysis, were laser fluence, laser energy per centimeter of vein length, diameter of the vein before treatment, and distance of the thrombus to the sapheno-femoral junction at day 1 after treatment. Finally, multiple regression analysis selected laser fluence (p=0.004, odds ratio=0.40 J/cm2) as the relevant risk factor for ELT failure or recanalization.

CONCLUSION: ELT failure seems to be related to the administration of low laser fluences.