Thigh Cuffs as a Countermeasure for Ocular Changes in Simulated Weightlessness

Astronauts exposed to prolonged weightlessness experience hyperopic shifts and structural alterations in the eye (e.g., choroidal folds and optic disc edema),1 a condition referred to as spaceflight-associated neuro-ocular syndrome (SANS). Loss of the hydrostatic pressure gradient during spaceflight reduces venous volume in the lower extremities, leading to a headward fluid shift. This headward fluid shift resulting from the weightlessness environment of spaceflight has been hypothesized to be the initiating factor for ocular-related changes that develop in astronauts during long-duration spaceflight.

Source: Ophthalmology - November 16, 2017 Category: Opthalmology Authors: Siva Balasubramanian, Tudor Tepelus, Michael B. Stenger, Stuart M.C. Lee, Steven S. Laurie, John H.K. Liu, Alan H. Feiveson, SriniVas R. Sadda, Alex S. Huang, Brandon R. Macias Tags: Reports Source Type: research