Neoplasms treatment by diode laser with and without real time temperature control on operation zone

Results of nevus, papilloma, dermatofibroma, and basal cell skin cancer in vivo removal by a 980±10 nm diode laser with "blackened" tip operating in continuous (CW) mode and automatic power control (APC) mode are presented. The collateral damage width and width of graze wound area around the collateral damage area were demonstrated. The total damage area width was calculated as sum of collateral damage width and graze wound area width. The mean width of total damage area reached 1.538±0.254 mm for patient group with nevus removing by 980 nm diode laser operating in CW mode, papilloma − 0.586±0.453 mm, dermatofibroma − 1.568±0.437 mm, and basal cell skin cancer − 1.603±0.613 mm. The mean width of total damage area reached 1.201±0.292 mm for patient group with nevus removing by 980 nm diode laser operating in APC mode, papilloma − 0.413±0.418 mm, dermatofibroma − 1.240±0.546 mm, and basal cell skin cancer − 1.204±0.517 mm. It was found that using APC mode decreases the total damage area width at removing of these nosological neoplasms of human skin, and decreases the width of graze wound area at removing of nevus and basal cell skin cancer. At the first time, the dynamic of output laser power and thermal signal during laser removal of nevus in CW and APC mode is presented. It was determined that output laser power during nevus removal for APC mode was 1.6±0.05 W and for CW mode – 14.0±0.1 W. This difference can explain the decrease of the total damage area width and width of graze wound area for APC mode in comparison with CW mode.