2 Clinical Trials for Various Conditions
This study is being done to prevent changes in the vision of astronauts during prolonged residence on the International Space Station or a mission to Mars. This project will provide data about the efficacy of lower body negative pressure to mimic daily upright posture by intermittently lowering central venous pressure while in simulated microgravity (3 days of bed rest). The investigators expect that 3 days of bed rest will increase choroid thickness, and choroid area. The investigators hypothesize that nightly LBNP (-20mmHg) will prevent these changes.
The goal of this study is to understand the impact of space travel on the eyes. Space flight impacts numerous aspects of ocular anatomy and physiology. Current hypotheses are based on pressure changes within and around the optic nerve. Retinal and choroid blood drainage may be affected by microgravity associated cerebrospinal fluid pressure changes. Recently, a new imaging modality, Optical Coherence Tomography Angiography (OCTA), has been able to reveal micro vascular changes in the retina and choroid. To date, no microgravity ocular imaging tests have been published using OCTA. In this study the researchers aim to describe microgravity circadian choroidal and retinal vasculature using multimodal imaging including OCTA to better understand space associated ocular changes.