Ocular histoplasmosis syndrome.

The Macular Photocoagulation Study (MPS) is a multi-center clinical trial supported by the National Eye Institute whose purpose is to assess argon laser photocoagulation as a treatment for choroidal neovascular membranes (NVMs) that do not involve the fovea. The MPS documented that in patients with ocular histoplasmosis syndrome argon laser photocoagulation in comparison with no treatment can reduce the risk of severe visual loss from 46 to 13% in the first two years. Accordingly, patients with ocular histoplasmosis and NVMs outside the fovea are advised to undergo prompt treatment with argon laser photocoagulation.