Ocular histoplasmosis syndrome.

Ocular histoplasmosis syndrome is prevalent among persons living in the vicinity of the Ohio River Valley. Only a small proportion of patients with ophthalmoscopic evidence of prior Histoplasma capsulatum infection ever develop visual symptoms. Visual morbidity usually follows the development of a macular choroidal neovascular membrane which causes serous or hemorrhagic detachment, or both, of pigment epithelium and sensory retina. Fluorescein angiography is useful in documenting the choroidal neovascular membrane and in demonstrating its precise location with respect to the retinal capillary-free zone. tthe fluorescein angiographic appearance and location are used to determine whether or not such membranes are amenable to argon laser photocoagulation. The true role of photocoagulation in the management of histoplasmic maculopathy awaits the results of a randomized clinical trial.