Argon laser photocoagulation in the treatment of presumed histoplasmic choroiditis.

Our experience with the evolving techniques we have reported has not resulted in significant increases in visual acuity over pretreatment levels. However, argon laser photocoagulation, properly given, does destroy subretinal neovascularization. The most significant points of technique are (1) heavy treatment of the entire frond; (2) accomplishment of this usually by a 200-mu spot size, 0.2 to 0.5 second, at 300 to 400 mW. power; (3) the eye under retrobulbar anesthesia, and (4) following the case at intervals of three to five days until the neovascular frond is destroyed. If the edge of the neovascular frond is within 200 mu of the fovea, treatment presents a very definite hazard to foveal vision and should be attempted only in the most experienced hands and on only the best-informed patients.