Orbital and Intracranial Effects of Microgravity: Findings at 3-T MR Imaging

Retrospective MR analysis of 27 astronauts exposed to microgravity revealed various combinations of optic nerve sheath distention, posterior globe flattening, optic disc protrusion, increased optic nerve diameter, and moderate concavity of the pituitary gland with posterior stalk displacement, which are hypothesized to be related to intracranial hypertension and represent a potential limitation to long-duration space travel.