Altitude retinopathy on Mount Everest, 1989.

The authors studied prospectively the incidence of and risk factors for high altitude retinal hemorrhages among 14 members of the 1989 American Everest Expedition. All subjects had comprehensive eye examinations and fundus photography performed at sea level before the expedition and again at the Mt. Everest Base Camp after 6 weeks of exposure to altitudes between 5300 and 8200 meters. Asymptomatic intraretinal hemorrhages were found in five eyes of four climbers. An additional eye of one of these climbers had a central retinal vein occlusion with vitreous hemorrhage, which reduced visual acuity to counting fingers. Higher baseline intraocular pressure and use of nonsteroidal anti-inflammatory drugs were found to be significant risk factors for development of altitude retinopathy.