Special aspects of continuous fixed-power laser action to skin effects

Abstract

Continuous fixed-power laser exposure to human tissue (in particular, to cutaneous neoplasms) will increase the temperature of the heated tissue only to a certain stationary value. Continued irradiation with the same power and constant target absorbing capacity will not lead to further increase of the target temperature. However, surrounding healthy tissue will warm up, and it can cause a thermal damage. The aim of the present work is to obtain nomographs for determining the required power density and the duration of exposure for heating cutaneous neoplasms to the desired temperature (for example, denaturing temperature of collagen, vaporization or incineration of human tissue), as well as to carry out clinical testings of the proposed technique for selecting laser radiation parameters. In the course of the work, the researchers developed formulas for estimating the value of steady-state temperature. Experimentation was carried out on the mock-up sample in order to determine the applicability of the formulas obtained. Based on them, simple ratios were obtained, and with their help the optimal radiation parameters of semiconductor laser (wavelength 808 nm) were determined for the removal of papillomas, fibrosis, nevi simple and senile hyperkeratoses. The calculated ratio efficiency is shown in removing cutaneous neoplasms with minimal thermal damage to surrounding tissues. The work was carried out in OOO «Partner Beauty», Moscow.