Spaceflight-Induced Intracranial Hypertension and Visual Impairment: Pathophysiology and Countermeasures.
Physiol Rev
; 98(1): 59-87, 2018 01 01.
Article
en En
| MEDLINE
| ID: mdl-29167331
ABSTRACT
Visual impairment intracranial pressure (VIIP) syndrome is considered an unexplained major risk for future long-duration spaceflight. NASA recently redefined this syndrome as Spaceflight-Associated Neuro-ocular Syndrome (SANS). Evidence thus reviewed supports that chronic, mildly elevated intracranial pressure (ICP) in space (as opposed to more variable ICP with posture and activity on Earth) is largely accounted for by loss of hydrostatic pressures and altered hemodynamics in the intracranial circulation and the cerebrospinal fluid system. In space, an elevated pressure gradient across the lamina cribrosa, caused by a chronic but mildly elevated ICP, likely elicits adaptations of multiple structures and fluid systems in the eye which manifest themselves as the VIIP syndrome. A chronic mismatch between ICP and intraocular pressure (IOP) in space may acclimate the optic nerve head, lamina cribrosa, and optic nerve subarachnoid space to a condition that is maladaptive to Earth, all contributing to the pathogenesis of space VIIP syndrome. Relevant findings help to evaluate whether artificial gravity is an appropriate countermeasure to prevent this seemingly adverse effect of long-duration spaceflight.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Postura
/
Vuelo Espacial
/
Trastornos de la Visión
/
Presión Intracraneal
/
Hipertensión Intracraneal
/
Presión Intraocular
Tipo de estudio:
Etiology_studies
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Physiol Rev
Año:
2018
Tipo del documento:
Article