Fig. 20. Cyclodiathermy treatment of the ciliary body to control glaucoma. A. Gross photograph illustrates extensive areas of depigmentation mainly in the region of the pars plana (arrows) rather than the pars plicata. B. Light micrograph of the region of the pars plana illustrates an extensive area of tissue degeneration of the pars plana (between arrows) in the late postoperative course. C. Light micrograph of the destructive effects of cyclocryotherapy also in the region of the pars plana and pars plicata. The ciliary epithelium in the early postoperative period is necrotic and cystic. (Hematoxin-eosin stain; A, × 8; B, × 16.)