DYNAMIC REFLECTOMETER FOR CONTROL OF LASER PHOTOCOAGULATION ON THE RETINA

In retinal laser photocoagulation, constant exposure parameters do not result in identical lesions. This lack of reproducibility increases t he rate of complications from over- or undertreatment and inhibits det ermination of the optimal treatment endpoints for different retinal di sorders. To this end, a feedback-controlled photocoagulator could make retinal photocoagulation a safer, more reproducible, and faster proce dure. A dynamic confocal reflectometer was integrated into a slit lamp laser delivery system. Real-time reflectance changes on the retinas o f pigmented rabbits were obtained by monitoring the increasing back-sc attered light of the coagulating beam during argon laser photocoagulat ion. Reproducible temporal reflectance patterns were measured that cor related with ophthalmoscopically assessed lesion intensity independent of the exposure parameters, the transparency of the optical media, an d the focusing conditions. As a step toward the development of a feedb ack-controlled photocoagulator, the confocal reflectometer has been pr oven in animal trials closely resembling clinical practice. (C) 1994 W iley-Liss, Inc.