Objectives To determine the incidence of optic disc swelling as a possible indicator of
cerebral edema in a large group of healthy mountaineers exposed to very high altitudes and
to correlate these findings with various clinical and environmental factors and occurrence of
acute mountain sickness and high-altitude cerebral edema. Methods This multidisciplinary,
prospective, observational cohort study was performed in 2005 within the scope of a medical
research expedition to Muztagh Ata (7546 m [24 751 ft]) in Western Xinjiang Province …