The Characteristics of Experimental Laser Coagulations of the Retina

Abstract

Introduction The technique of laser photocoagulation offers great therapeutic promise to the clinician. In this laboratory a program is under way to evaluate the ocular effects produced by lasers. An important aspect of this study is the documentation of the histologic characteristics of lesions produced by laser photocoagulation. This report defines and illustrates the microscopic appearance of laser coagulations and relates these findings to the clinical appearance of the lesions as observed by ophthalmoscopy. The more familiar xenon arc coagulations are compared to those obtained with the laser. Previous Reports The microscopic characteristics of retinal coagulations produced by the xenon arc photocoagulator have been described.^1-3 The investigation by Okun particularly related the histologic appearance of the lesion to the intensity of the treatment. In mild lesions there was coagulation necrosis of all retinal layers one hour after treatment. The most marked effect was in the outer layers where hydropic