The possibility of endovenous laser coagulation using Ti-containing optothermal fiber converters (TOTFC) is discussed. Optical and thermal models have been developed to estimate the distribution of radiation and temperature in the vein during endovenous laser coagulation when using TOTFC for 532 nm, 810 nm, 980 nm, 1064 nm, 1310 nm, 1470 nm, 1910 nm and 2100 nm wavelengths. Radiation intensity distributions around the TOTFC and on the vessel wall were obtained and evaluated. The absorbance efficiency of laser energy with different wavelengths for TOTFC has been calculated. As a result of the thermal calculation, for different wavelengths, average laser power from 8 to 15 W with traction speed from 1 to 7 mm/s, the thermodynamics of the blood vessel wall and TOTFC was determined. During endovenous laser coagulation temperature inside TOTFC exceeds 500°C. The optimal combinations of average laser power and titanium-containing converter traction speed are defined for coagulation of the vein wall.
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