Cyclocryotherapy: a light and electron microscopic study.

Previous anatomic studies of the effects of cyclocryotherapy have produced confusing results because of variations in technique and instrumentation. Five eyes from three patients treated by a standard technique were compared to the eyes of rhesus monkeys that received identical treatment. The monkeys were given horseradish peroxidase intravenously 30 minutes before enucleation. Hemorrhage, edema, and epithelial disruption were characteristic of the acute lesions. Later, the nonpigmented ciliary epithelium disappeared, but by two months, normal morphology was restored. Normal peroxidase flow reappeared at a similar time. Anatomic changes in the human and monkey eyes were similar.