Mader T H, Gibson C R, Caputo M, Hunter N, Taylor G, Charles J, Meehan R T
Madigan Army Medical Center, Tacoma, Washington 98431.
Am J Ophthalmol. 1993 Mar 15;115(3):347-50. doi: 10.1016/s0002-9394(14)73586-x.
We measured intraocular pressures and retinal vascular diameters from 11 subjects during 20 seconds of microgravity produced by parabolic flight on board a KC-135 aircraft. Intraocular pressures increased 58% during parabolic flight compared to baseline values (19 +/- 1 mm Hg vs 12 +/- 1 mm Hg, respectively; P < .001). A 4% reduction in the caliber of retinal arteries was also noted during microgravity, but this change did not achieve statistical significance (7.8 +/- 0.3 pixels at zerogravity vs 8.1 +/- 0.3 pixels at 1g; P = .07). The increase in intraocular pressure and trend of arteries to constrict are thought to result from cephalad shifts in intravascular and extravascular body fluids as a result of the absence of the 1g hydrostatic gradient. The results of our study confirm that this fluid shift and its effects on the eye occur rapidly, within 20 seconds of exposure to microgravity.
我们在KC - 135飞机上进行抛物线飞行产生的20秒微重力期间，测量了11名受试者的眼压和视网膜血管直径。与基线值相比，抛物线飞行期间眼压增加了58%（分别为19±1毫米汞柱和12±1毫米汞柱；P <.001）。在微重力期间还观察到视网膜动脉管径减小了4%，但这种变化未达到统计学显著性（零重力时为7.8±0.3像素，1g重力时为8.1±0.3像素；P =.07）。眼压升高和动脉收缩趋势被认为是由于缺乏1g静水压力梯度导致血管内和血管外体液向头侧转移所致。我们的研究结果证实，这种体液转移及其对眼睛的影响在暴露于微重力的20秒内迅速发生。
