Fluid distribution during spaceflight and impact on brain and vision health is an emerging field of high-priority research in the NASA human space program. International Space Station astronauts have developed ocular refraction changes during prolonged spaceflight. Within this book, experts review current data related to fluid shifts during microgravity exposure and the impact of fluid shifts on astronaut health.This work also compares current astronaut health problems with Earth-based health conditions such as elevated intracranial pressure and glaucoma. Chapters include discussion of altered fluid distribution, including intracellular and extracellular fluid shifts, eye morphology and vision disturbances, and intraocular pressure. In addition, chapters will include a discussion of advanced non-invasive technologies to investigate the abovementioned fluid volume and pressure variables.As such, the book aims to bridge health professionals, researchers, and science professionals by a presentation of ophthalmology topics critical to future human space exploration, thus providing new perspectives to solve emerging brain and eye disease on Earth and in Space.