Comparative Analysis ofVenous and Paravenous Tissue Damage During Endovascular Laser Ablation with Wavelengths of 1470 and 1940 nm

The objective of the study was to compare the results of endovenous laser ablation (EVLO) with wavelengths of 1470 and 1940 nm at powers of 5 and 8.5 watts. Materials and methods. In an experiment on sheep, EVLO of the subcutaneous veins of the extremities was performed using a laser with wavelengths of 1470 and 1940 nm and powers of 5 and 8.5 W. Before, during, and 7 days after laser exposure, ultrasound and histological examination of coagulated veins was performed with an assessment of the blood flow rate, the presence of a thrombus in the vein, as well as thermal damage to paravenous tissues. Results. A linear endovenous energy density (LEED) of 25 J/cm at 1470 nm was insufficient for achieving complete vein occlusion while preserving blood flow. Although the LEED value of 42.5 J/cm contributes to the complete vein occlusion, thermal damage to paravenous tissues was observed. The use of a wavelength of 1940 nm and a LEED of 25 J/cm was associated with complete vein occlusion and minor damage to paravenous tissues. Increasing the LEED to 42.5 J/cm causes coagulation necrosis and destruction of the vein wall and paravenous tissues. Conclusion. The optimal mode for EVLO is 1940 nm wavelength with a LEED of 25 J/cm, providing sufficient vein occlusion without significant damage to paravenous tissues.