Lower Body Negative Pressure for Spaceflight Associated Neuro-ocular Syndrome: A Systematic Review and Meta-Analysis
DOI:
https://doi.org/10.37275/bsm.v9i12.1454Keywords:
Intraocular pressure, Lower body negative pressure, Meta-analysis, Microgravity, Spaceflight associated neuro-ocular syndromeAbstract
Background: Spaceflight associated neuro-ocular syndrome (SANS) is a critical health risk for astronauts on long-duration missions, characterized by potentially vision-altering ocular changes. Lower body negative pressure (LBNP) is a primary countermeasure designed to reverse the foundational cephalad fluid shifts. This study provides the first rigorous, quantitative synthesis of LBNP's efficacy on key SANS-related ocular parameters.
Methods: Following PRISMA guidelines, a systematic search of PubMed, ScienceDirect, and the Cochrane Library (2015–2025) was conducted. Studies quantifying the effect of LBNP on intraocular pressure (IOP), optic nerve sheath diameter (ONSD), or choroidal thickness (CT) in microgravity or its ground-based analogs were included. A random-effects meta-analysis calculated the pooled mean difference (MD). Leave-one-out sensitivity analysis and assessment of publication bias were performed to ensure robustness.
Results: Seven studies (N=89 subjects) met the criteria. The meta-analysis demonstrated that LBNP application resulted in statistically significant reductions in IOP (MD = -2.15 mmHg; 95% CI [-3.01, -1.29]; p < 0.001), ONSD (MD = -0.31 mm; 95% CI [-0.45, -0.17]; p < 0.001), and subfoveal Choroidal Thickness (MD = -18.50 µm; 95% CI [-25.65, -11.35]; p < 0.001). Subgroup analysis revealed a more pronounced effect in ground-based studies. The results were robust in sensitivity analyses, and funnel plots suggested a low risk of publication bias.
Conclusion: This meta-analysis provides robust, quantitative evidence supporting LBNP's efficacy in acutely mitigating the cardinal structural signs of SANS. By directly counteracting the underlying pathophysiology, LBNP is affirmed as a cornerstone countermeasure technology essential for preserving astronaut ocular health during the upcoming era of deep space exploration.
Authors
- Fabiola Supit1*
- I Made Ady Wirawan2
- I Gusti Ayu Made Juliari1
- Ida Ayu Ary Pramita1
- 1Department of Ophthalmology, Faculty of Medicine, Universitas Udayana/Prof. Dr. I.G.N.G. Ngoerah General Hospital, Denpasar, Indonesia
- 2Department of Public Health and Preventive Medicine, Faculty of Medicine, Universitas Udayana, Denpasar, Indonesia
Corresponding author Fabiola Supit — fabiola.supit.md@gmail.com
Article history
- Submitted
- Accepted
- Published
Downloads
Published
Issue
Section
License
Copyright and licensing
Copyright in each article remains with the author(s). Authors grant Bioscientia Medicina: Journal of Biomedicine and Translational Research a non-exclusive right of first publication and the right to identify itself as the original publisher. No exclusive transfer of copyright is required.
All articles are published under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (CC BY-NC-SA 4.0): https://creativecommons.org/licenses/by-nc-sa/4.0/. Users may copy, redistribute, remix, transform, and build upon the material for non-commercial purposes, provided appropriate attribution is given, a link to the license is supplied, changes are indicated, and adaptations are distributed under the same license.
The license applies to the article's scholarly content unless a credit line states otherwise. Third-party material may be subject to separate rights. Authors retain patent, trademark, moral, and research-data rights. The copyright year follows the article's publication date.











