The endovenous laser treatment of varicose veins has been using for several years with clinical results comparable to traditional surgery.Many controversies still exist in the literature in terms of parameters of laser generator.The aim of the study was the standardisation of the procedure and set-up of the optimal technical parameters to achieve maximal vein shrinkage.The insuficient trunks of saphenous veins stripped during the traditional strippping procedure were irradiated with the laser energy delivered by the diode generator emitting 980 nm laser beam.The study cohort consisted of 2 groups-in the 1st group veins were filled with the blood(n=139),in the 2nd the veins were empty(n=140)to simulate the patients position on the operating table.Base on our experiments,we recommend photocoagulation with lower or medium power (8-12W)and slower pull-back(0.2-2mm/s)to achieve the sufficient energy per centimeter of the vein and the optimal long-term outcome.