APPROACH:

The data collected will mirror MRID requirements and testing performed during annual medical exams; however, two additional tests will be performed and the frequency of postflight testing will be increased to more accurately assess changes that occur in the visual, vascular, and central nervous systems.

The preflight MRID required tests are an MRI at launch minus (L-) 21-18 months; Ocular Ultrasound at L- 9-6 months; Vision Testing [Fundoscopy, Intraocular Pressure (IOP/Tonometry), Visual Acuity, Amsler Grid, OCT, Optical Biometry, Refraction, Threshold Visual Fields,]. During Vision Testing, subjects will be administered dilating and numbing agents) at L- 21-18 months and L- 9-6 months. The tests that will be done in addition to MRID requirements are Blood Pressure (BP) at time of IOP (Tonometry) at L- 21-18 months and L- 9-6 months, Vascular Compliance (Cardiac Ultrasound and BP), and TCD at L- 9-6 months.

The postflight MRID required tests are an MRI, Ocular Ultrasound, and Vision Testing at return plus (R+) 1-3 days. In addition to these MRID requirements, BP at time of IOP (Tonometry), Vascular Compliance (Cardiac Ultrasound and BP), and TCD will also be done on R+1-3 days and the entire suite of tests will be done at R+30, R+90, R+180, and R+360 days.

Inflight, the data collected will mirror MRID requirements; however, three additional tests will be performed and the frequency of inflight testing will be increased to more accurately assess changes that occur in the visual, vascular, and central nervous systems. All activities within a Flight Day session may occur within a 5-day window. The inflight MRID required tests are Vision Testing and Vision Questionnaire, Ocular Ultrasound, Fundoscopy, and OCT on flight day (FD) 30, FD 90, and return minus (R-) 30. In addition to these MRID requirements, these tests will also be conducted on FD 10, FD 60, and FD 120. The additional tests, IOP (Tonometry) w/ BP, Vascular Compliance (Cardiac Ultrasound and BP), and TCD, will be conducted on FD 10, FD 30, FD 60, FD 90, FD 120, and R-30.

For extended duration missions, the Inflight operations will increase to FD 10, 30*, 90*, 150*, 210*, 270*, R-30* for all Ocular Health testing, where * indicates data-sharing with existing MRID sessions.

RESULTS: :
This experiment is in progress. Results will be available at a later date.

Giovanni T, Cromwell RL, Zanello SB, Yarbough PO, Ploutz-Snyder RJ, Bernard F. Godley BF, and Vizzeri G. Ocular outcomes comparison between 14- and 70-day head-down-tilt bed rest. Investigative Ophthalmology and Visual Science. 2016. February; 57(2): 495–501. [DOI]

Mader TH, Gibson CR, Otto CA, Sargsyan AE, Miller NR, Subramanian PS, et al. Persistent Asymmetric Optic Disc Swelling After Long-duration Space Flight: Implications for Pathogenesis. Journal of Neuro-ophthalmology. 2017. June 1; 37(2):133–9.

Vision

Blood pressure

Intracranial pressure

Intraocular pressure

Amsler grid

Aqueductal cross-sectional area

Average minimum rim width, global

Average peripappillary choroidal thickness, global

Blood pressure, diastolic

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