ABSTRACT
The authors' own clinical observations have shown that a pressure-lowering effect in secondary glaucomas resistant to therapy can be obtained by photocoagulation of the pars plicata of the ciliary body using an argon laser. In order to be able to estimate the damaging effect of photocoagulation and thus to be able to administer it in a sensible dose, the authors applied this technique to four patients with tumorous eyes that had to be enucleated, with a subsequent histological and electron-microscopical scrutiny. The laser energy was varied from 750 to 2000 mW at a constant exposure time of 0.2 s and a dot size of 100 micrograms. With clear-refracting media an energy of 1000 mW brought about coagulative effects without any substantial side-effects. Damage was then generally restricted to the aqueous humorproducing formation, i.e., the ciliary epithelium and the adjacent stromal part.