Ophthalmic Changes Associated with Long-Term Exposure to Microgravity.

This review discusses recent publications on the problem of ophthalmic changes associated with long-term effects of microgravity during space flights. Described changes include hyperopic shift of refraction, change in intraocular pressure, increased intracranial pressure, changes in the choroid and retina tissues, and swelling of the optic nerve. These effects are caused by redistribution of blood and fluid to the upper half of the body, increased intracranial pressure and congestion of venous blood and lymph in the upper half of the body and head. The reviewed also discusses other factors that may triggervision impairment caused by microgravity. Photographic illustrations of changes are also provided.