Photothermal, cryogenic, and diathermic effects of retinal adhesive force in vivo.

Abstract

Argon laser photocoagulation, cryoretinopexy, and diathermy of moderate intensity is applied to 140 rabbit eyes. Retinal adhesive force is measured from 1 day to 6 months following the treatment, using the authors' new in vivo method. A small retinal detachment is induced within the area surrounded by the burns. At the moment when the detachment starts to expand beyond the burns, subretinal pressure is measured using a resistance servo-nulling method. Retinal adhesive force is then calculated according to Laplace's law and compared with that of untreated eyes. Both photocoagulation and diathermy enhanced adhesiveness within 24 hours to 128% and 122%, respectively, of normal levels. Cryoretinopexy reduced the retinal adhesiveness during the first week, but afterwards generated as much adhesiveness as the other two methods. Beyond 6 months, under the conditions described here by the authors, the adhesive force was stronger after diathermy (279%) than after cryoretinopexy (214%) or laser photocoagulation (220%).