Taibbi Giovanni, Young Millennia, Vyas Ruchi J, Murray Matthew C, Lim Shiyin, Predovic Marina, Jacobs Nicole M, Askin Kayleigh N, Mason Sara S, Zanello Susana B, Vizzeri Gianmarco, Theriot Corey A, Parsons-Wingerter Patricia
Department of Ophthalmology and Visual Sciences, The University of Texas Medical Branch at Galveston, Galveston, TX, USA.
NASA Johnson Space Center, Houston, TX, USA.
NPJ Microgravity. 2021 Oct 14;7(1):38. doi: 10.1038/s41526-021-00165-5.
The Spaceflight Associated Neuro-ocular Syndrome (SANS), associated with the headward fluid shifts incurred in microgravity during long-duration missions, remains a high-priority health and performance risk for human space exploration. To help characterize the pathophysiology of SANS, NASA's VESsel GENeration Analysis (VESGEN) software was used to map and quantify vascular adaptations in the retina before and after 70 days of bed rest at 6-degree Head-Down Tilt (HDT), a well-studied microgravity analog. Results were compared to the retinal vascular response of astronauts following 6-month missions to the International Space Station (ISS). By mixed effects modeling, the trends of vascular response were opposite. Vascular density decreased significantly in the 16 retinas of eight astronauts and in contrast, increased slightly in the ten retinas of five subjects after HDT (although with limited significance). The one astronaut retina diagnosed with SANS displayed the greatest vascular loss. Results suggest that microgravity is a major variable in the retinal mediation of fluid shifts that is not reproduced in this HDT bed rest model.
航天相关神经-眼部综合征（SANS）与长期任务期间微重力环境下发生的头向体液转移有关，仍然是人类太空探索中健康和性能方面的高优先级风险。为了帮助描述SANS的病理生理学特征，美国国家航空航天局（NASA）的血管生成分析（VESGEN）软件被用于绘制和量化在6度头低位倾斜（HDT）卧床休息70天前后视网膜血管的适应性变化，HDT是一种经过充分研究的微重力模拟环境。将结果与宇航员执行6个月国际空间站（ISS）任务后的视网膜血管反应进行了比较。通过混合效应建模，血管反应趋势相反。八名宇航员的16只视网膜血管密度显著降低，相比之下，五名受试者的10只视网膜在HDT后略有增加（尽管显著性有限）。唯一被诊断患有SANS的宇航员视网膜显示出最大的血管损失。结果表明，微重力是视网膜介导体液转移中的一个主要变量，而这种HDT卧床休息模型无法再现这一变量。
