Evidence map›Paper›PMID 40545016›Full record

Trial reportAmerican journal of ophthalmology2025

Optic Nerve Vasculature and Countermeasure Assessment in a Bedrest Analogue of Spaceflight-Associated Neuro-Ocular Syndrome.

Ye He, Rustum Karanjia, Xiaowei Zhang, Daniel Wanderer, Evan Walker, Seung Hyen Lee, Matthew J Poczatek, Cambria S O'Grady, Kenneth M Marion, Millennia Young and 7 more

Abstract readRandomized Controlled Trial
PubMed Full text at PMC Publisher
In one paragraph

Trial report in American journal of ophthalmology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

17 authors.

Ye HeFrom the Doheny Eye Institute and University of California (Y.H., R.K., K.M.M., and S.R.S.), Los Angeles, California, USA.
Rustum KaranjiaFrom the Doheny Eye Institute and University of California (Y.H., R.K., K.M.M., and S.R.S.), Los Angeles, California, USA; Department of Ophthalmology (R.K.), Ottawa Eye Institute, University of Ottawa, Ottawa, Canada.
Xiaowei ZhangHamilton Glaucoma Center, Shiley Eye Institute (X.Z., D.W., E.W., S.H.L., and A.S.H.), The Viterbi Family Department of Ophthalmology, University of California, San Diego, California, USA.
Daniel WandererHamilton Glaucoma Center, Shiley Eye Institute (X.Z., D.W., E.W., S.H.L., and A.S.H.), The Viterbi Family Department of Ophthalmology, University of California, San Diego, California, USA.
Evan WalkerHamilton Glaucoma Center, Shiley Eye Institute (X.Z., D.W., E.W., S.H.L., and A.S.H.), The Viterbi Family Department of Ophthalmology, University of California, San Diego, California, USA.
Seung Hyen LeeHamilton Glaucoma Center, Shiley Eye Institute (X.Z., D.W., E.W., S.H.L., and A.S.H.), The Viterbi Family Department of Ophthalmology, University of California, San Diego, California, USA; Department of Ophthalmology (S.H.L.), Nowon Eulji Medical Center, Eulji University College of Medicine, Seoul, Republic of Korea.
Matthew J PoczatekJES Tech (M.J.P.), Houston, Texas, USA.
Cambria S O'GradyAegis Aerospace (C.S.O.), Webster, Texas, USA.
Kenneth M MarionFrom the Doheny Eye Institute and University of California (Y.H., R.K., K.M.M., and S.R.S.), Los Angeles, California, USA.
Millennia YoungNASA, Johnson Space Center (M.Y. and B.R.M.), Houston, Texas, USA.
Stefan MoestlInstitute of Aerospace Medicine (S.M., E.M., and C.S.), German Aerospace Center, Cologne, Germany.
Edwin MulderInstitute of Aerospace Medicine (S.M., E.M., and C.S.), German Aerospace Center, Cologne, Germany.
Claudia SternInstitute of Aerospace Medicine (S.M., E.M., and C.S.), German Aerospace Center, Cologne, Germany.
Srinivas R SaddaFrom the Doheny Eye Institute and University of California (Y.H., R.K., K.M.M., and S.R.S.), Los Angeles, California, USA.
Steven S LaurieKBR (S.S.L.), Houston, Texas, USA.
Brandon R MaciasNASA, Johnson Space Center (M.Y. and B.R.M.), Houston, Texas, USA.
Alex S HuangHamilton Glaucoma Center, Shiley Eye Institute (X.Z., D.W., E.W., S.H.L., and A.S.H.), The Viterbi Family Department of Ophthalmology, University of California, San Diego, California, USA. Electronic address: aahuang@health.ucsd.edu.

Funding

Vision BiostatisticsP30EY022589 · NEI · UNIVERSITY OF CALIFORNIA, SAN DIEGO · PI Radha Ayyagari · 2012 to 2026
$10.3M
NEI NIH HHS P30 EY022589
6 · The paper itself

Abstract

purposeTo evaluate cephalad fluid shift countermeasures (CMs) as well as optic nerve structure and vasculature in a strict and chronic head-down tilt bedrest (HDTBR) model of Spaceflight-Associated Neuro-ocular Syndrome (SANS).

designA prospective randomized interventional study.

participantsForty-seven subjects.

methodsAn HDTBR study was performed with 4 groups. One group underwent 30 days of strict HDTBR. The remaining groups did the same with one of three fluid shift CMs: lower body negative pressure, exercise with veno-constrictive thigh cuffs (EX + CUFF), or intermittent upright posture (all groups, n = 11-12). All subjects underwent testing pre-BR, in HDTBR, and after returning to an upright posture. Ocular tests included optical coherence tomography (OCT), OCT-angiography, multicolor imaging, and intravenous fluorescein angiography. Total retinal thickness 250 microns away from Bruch's membrane opening (TRT250) was measured using a National Aeronautics and Space Administration-defined convention of ∆TRT250 > 20 μm as OCT-determined disc edema in SANS.

resultsOnly the upright posture (which intermittently reverses headward fluid shifts) resulted in a ∆TRT250 of <20 microns (18.6 ± 5.5 μm; mean ± 95% CI). The remaining three groups (including two CMs) showed a ∆TRT250 of > 20 microns with no differences between groups. As a result, all subjects were then combined. Pre-HDTBR cup width, depth, and volume were associated with increasing ∆TRT250 (P = .001-.002). Increasing ∆TRT250 was associated with both increasing optic nerve hyperfluorescence on intravenous fluorescein angiography (P < .001-.002) and decreasing peripapillary perfusion density on OCT-angiography (P = .04). DISCUSSION: Upright posture is the first SANS CM to show a ∆TRT250 less than the National Aeronautics and Space Administration threshold for optic disc change in this HDTBR Earth-bound analogue of SANS, supporting the headward fluid-shift hypothesis in SANS. The inability to distinguish between the other conditions may have been due to risk factors that are not fully understood. This includes the risk factor of a smaller baseline optic nerve cup, which is associated with SANS-like changes in this study, and as previously shown in astronauts. Finally, the presence of optic disc vascular alterations (increased hyperfluorescence and decreased peripapillary perfusion density), which are also observed in Earth-bound disc edemas, highlights that optic nerve vascular damage is occurring.

Indexed as

Bed RestOptic NerveRetinal VesselsSpace FlightAdultFemaleFluid ShiftsFluorescein AngiographyHead-Down TiltHumansMaleMiddle AgedPapilledemaProspective StudiesSyndromeTomography, Optical Coherence

Identifiers

PMID40545016
PMCPMC12462775

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.