[The experimental validation of the clinical use of new surgical lasers]

A comparative evaluation has been carried out between the effects of surgical CO2-laser (lambda = 10.6 mcm) and lasers previously unused in medicine: Yag-erbium (lambda = 2.94 mcm) and YAG-erbium-in-glass lasers on biological tissue. The cutting properties of the lasers, nature of their effect on tissue and the period of healing of laser injury were studied morphologically. Effects of radiation on the energetic, biosynthetic and proliferative processes in the liver tissue, as well as the activity of transamination enzymes have been investigated. It has been shown that laser radiation of lambda = 1.54 and lambda = 2.94 mcm can destroy biological tissue with minimum inflammatory reaction as compared to CO2-laser. It has been ascertained that better marked changes in bioenergetics, aminotransferase activity, RNA and DNA contents are observed under the influence of CO2 and YAG-erbium lasers. Exposure of liver to YAG-erbium-in-glass laser radiation produced minimum changes in cells of the tissue contiguous to the injury. Thus, under its influence the majority of the investigated indices either changed insignificantly or improved. This might account for a positive effect of this laser on the dynamics and quality of the injury healing. The experimental studies gave basis for creation of working models of laser devices (lambda = 1.54 mcm) which are undergoing successful clinical trials at present.