Neuro-Ophthalmology of Outer Space

INTRODUCTION: Physiologic and pathologic systemic responses and novel but dramatic ocular changes are known to occur in the microgravity environment of outer space. The precise effects of the long duration space flight environment on the human eye and brain remain ill-defined but over the last decade, the United States National Aeronautics and Space Administration's (NASA) Space Medicine Division has documented varying degrees of optic disc edema, globe flattening, choroidal folds, cotton wool spots (CWS), and hyperopic refractive error shifts in astronauts during and after long-duration space flight.