Abstract
During long-duration spaceflight, approximately half of the astronauts develop a unique set of structural and functional neuro-ophthalmic changes to varying degrees including swelling of the optic disc, posterior ocular globe flattening, and hyperopic refractive error shifts. While the etiology of these changes remains unknown, hypothesized contributing factors include headward fluid shifting due to reduced gravity, cerebral venous congestion, increased intracranial pressure relative to the upright posture on Earth, and exposure to elevated carbon dioxide levels. Research efforts have turned to the development of spaceflight-compatible countermeasures to combat this spaceflight-associated neuro-ocular syndrome (SANS). Promising countermeasures include lower body negative pressure, thigh cuffs, and artificial gravity via human centrifugation, all aimed at redistributing body fluids to the lower limbs, similar to the upright position on Earth. Overall, effective countermeasures to the neuro-ophthalmic changes associated with extended exposure to the spaceflight environment, whether mechanical or pharmaceutical, must be developed to ensure both safe and successful deep space and exploration class missions in the future.
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References
Arbeille P, Herault S, Fomina G et al (1999) Influences of thigh cuffs on the cardiovascular system during 7-day head-down bed rest. J Appl Physiol 87:2168–2176. https://doi.org/10.1152/jappl.1999.87.6.2168
Balasubramanian S, Tepelus T, Stenger MB et al (2018) Thigh cuffs as a countermeasure for ocular changes in simulated weightlessness. Ophthalmology 125:459–460. https://doi.org/10.1016/j.ophtha.2017.10.023
Berdahl JP, Yu DY, Morgan WH (2012) The translaminar pressure gradient in sustained zero gravity, idiopathic intracranial hypertension, and glaucoma. Med Hypotheses 79:719–724. https://doi.org/10.1016/j.mehy.2012.08.009
Binder DK, Horton JC, Lawton MT, McDermott MW (2004) Idiopathic intracranial hypertension. Neurosurgery 54:538–552. https://doi.org/10.1227/01.NEU.0000109042.87246.3C
Campbell MR, Charles JB (2015) Historical review of lower body negative pressure research in space medicine. Aerosp Med Hum Perform 86:633–640. https://doi.org/10.3357/AMHP.4246.2015
Charles JB, Lathers CM (1994) Summary of lower body negative pressure experiments during space flight. J Clin Pharmacol 34:571–583
Clément G (2017) International roadmap for artificial gravity research. Npj Microgravity 3:29. https://doi.org/10.1038/s41526-017-0034-8
Clément GR, Bukley AP, Paloski WH (2015) Artificial gravity as a countermeasure for mitigating physiological deconditioning during long-duration space missions. Front Syst Neurosci 9. https://doi.org/10.3389/fnsys.2015.00092
Cooke WH, Ryan KL, Convertino VA (2004) Lower body negative pressure as a model to study progression to acute hemorrhagic shock in humans. J Appl Physiol 96:1249–1261. https://doi.org/10.1152/japplphysiol.01155.2003
Eklund A, Jóhannesson G, Johansson E et al (2016) The pressure difference between eye and brain changes with posture. Ann Neurol 80:269–276. https://doi.org/10.1002/ana.24713
Goswami N, Loeppky JA, Hinghofer-Szalkay H (2008) LBNP: past protocols and technical considerations for experimental design. Aviat Space Environ Med 79:459–471. https://doi.org/10.3357/ASEM.2161.2008
Hamilton DR, Sargsyan AE, Garcia K et al (2012) Cardiac and vascular responses to thigh cuffs and respiratory maneuvers on crewmembers of the international Space Station. J Appl Physiol 112:454–462. https://doi.org/10.1152/japplphysiol.00557.2011
Iliff JJ, Wang M, Liao Y et al (2012) A paravascular pathway facilitates CSF flow through the brain parenchyma and the clearance of interstitial solutes, including amyloid β. Sci Transl Med 4:147ra111. https://doi.org/10.1126/scitranslmed.3003748
Ito H, Kanno I, Ibaraki M et al (2003) Changes in human cerebral blood flow and cerebral blood volume during hypercapnia and hypocapnia measured by positron emission tomography. J Cereb Blood Flow Metab 23:665–670. https://doi.org/10.1097/01.WCB.0000067721.64998.F5
Kirsch KA, Baartz FJ, Gunga HC, Röcker L (1993) Fluid shifts into and out of superficial tissues under microgravity and terrestrial conditions. Clin Investig 71:687–689
Kramer LA, Sargsyan AE, Hasan KM et al (2012) Orbital and intracranial effects of microgravity: findings at 3-T MR imaging. Radiology 263:819–827. https://doi.org/10.1148/radiol.12111986
Law J, Van Baalen M, Foy M et al (2014) Relationship between carbon dioxide levels and reported headaches on the international Space Station. J Occup Environ Med 56:477–483. https://doi.org/10.1097/JOM.0000000000000158
Lawley JS, Petersen LG, Howden EJ et al (2017) Effect of gravity and microgravity on intracranial pressure. J Physiol 595:2115–2127. https://doi.org/10.1113/JP273557
Lee AG, Tarver WJ, Mader TH et al (2016) Neuro-ophthalmology of space flight. J Neuroophthalmol 36:85–91. https://doi.org/10.1097/WNO.0000000000000334
Macias BR, Liu JHK, Grande-Gutierrez N, Hargens AR (2015) Intraocular and intracranial pressures during head-down tilt with lower body negative pressure. Aerosp Med Hum Perform 86:3–7. https://doi.org/10.3357/AMHP.4044.2015
Mader TH, Gibson CR, Pass AF et al (2011) Optic disc edema, globe flattening, choroidal folds, and hyperopic shifts observed in astronauts after long-duration space flight. Ophthalmology 118:2058–2069. https://doi.org/10.1016/j.ophtha.2011.06.021
Marshall-Bowman K, Barratt MR, Gibson CR (2013) Ophthalmic changes and increased intracranial pressure associated with long duration spaceflight: an emerging understanding. Acta Astronaut 87:77–87. https://doi.org/10.1016/j.actaastro.2013.01.014
Marshall-Goebel K, Ambarki K, Eklund A et al (2016) Effects of short-term exposure to head-down tilt on cerebral hemodynamics: a prospective evaluation of a spaceflight analog using phase-contrast MRI. J Appl Physiol 120:1466–1473. https://doi.org/10.1152/japplphysiol.00841.2015
Marshall-Goebel K, Mulder E, Bershad E et al (2017) Intracranial and intraocular pressure during various degrees of head-down tilt. Aerosp Med Hum Perform 88:10–16. https://doi.org/10.3357/AMHP.4653.2017
Moore TP, Thornton WE (1987) Space shuttle inflight and postflight fluid shifts measured by leg volume changes. Aviat Space Environ Med 58:A91–A96
Norsk P, Bonde-Petersen F, Warberg J (1986) Influence of central venous pressure change on plasma vasopressin in humans. J Appl Physiol 61:1352–1357
Petersen LG, Petersen JCG, Andresen M et al (2016) Postural influence on intracranial and cerebral perfusion pressure in ambulatory neurosurgical patients. Am J Physiol Regul Integr Comp Physiol 310:R100–R104. https://doi.org/10.1152/ajpregu.00302.2015
Russomano T, Chotgues LF, Lima De Sa OA, et al (2001) Intra-ocular and venous pressures during head-down tilt. Geneve. 49th ICASM Conference (Volume 1)
Scott JM, Charles JB (2015) Lower body negative pressure as a VIIP countermeasure. In: Intracranial pressure and its effect on vision in space and on Earth. World Scientific, Singapore, pp 253–271
Shinojima A, Iwasaki K-I, Aoki K et al (2012) Subfoveal choroidal thickness and foveal retinal thickness during head-down tilt. Aviat Space Environ Med 83:388–393
Taibbi G, Cromwell RL, Kapoor KG et al (2013) The effect of microgravity on ocular structures and visual function: a review. Surv Ophthalmol 58:155–163. https://doi.org/10.1016/j.survophthal.2012.04.002
Trambovetskiĭ EV, Krotov VP, Korol’kov VI (1995) Intracranial pressure in monkeys during the flight of Cosmos-2229. Aviakosm Ekolog Med 29:37–41
Yarmanova EN, Kozlovskaya IB, Khimoroda NN, Fomina EV (2015) Evolution of Russian microgravity countermeasures. Aerosp Med Hum Perform 86:32–37. https://doi.org/10.3357/AMHP.EC05.2015
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This work was supported by the Translational Research Institute through Cooperative Agreement NNX16AO69A.
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Marshall-Goebel, K. (2022). Neuro-ocular Effects of Spaceflight. In: Pathak, Y.V., Araújo dos Santos, M., Zea, L. (eds) Handbook of Space Pharmaceuticals. Springer, Cham. https://doi.org/10.1007/978-3-030-05526-4_1
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