Thermal damage of the inner vein wall during endovenous laser treatment: key role of energy absorption by intravascular blood.

background. Despite the clinical efficacy of endovenous laser treatment (EVLT), its mode of action is incompletely understood. objective. To evaluate the role of intravascular blood for the effective transfer of thermal damage to the vein wall through absorption of laser energy. methods. Laser energy (15 J/pulse, 940 nm) was endovenously administered to explanted greater saphenous vein (GSV) segments filled with blood (n = 5) or normal saline (n = 5) in addition to GSVs under in vivo conditions immediately prior to stripping. Histopathology was performed on serial sections to examine specific patterns of damage. Furthermore, in vitro generation of steam bubbles by different diode lasers (81…