Demographic and Ocular Factors Associated with Suprachoroidal Space Thickness in Healthy Eyes.
PURPOSE: The suprachoroidal space (SCS) is an emerging route for drug delivery and gene therapy. Here, we analyze demographic and ocular factors associated with SCS visibility and thickness on enhanced-depth imaging OCT (EDI-OCT) in a large cohort of healthy human eyes to better understand variations in macular SCS measurements. DESIGN: Retrospective, cross-sectional study. SUBJECTS: Six hundred twenty-four healthy eyes of 624 patients with no retinal pathologies. METHODS: We analyzed EDI-OCT images of eyes with no retinal pathologies from patients seen at the University of California, Davis between September 1, 2014 and December 31, 2023. We performed image segmentation and measured SCS visibility and thickness along the 6-mm segment around the fovea, as well as retinal and choroidal thicknesses. Univariate and multivariate regression analyses were used to determine the association of SCS visibility and thickness with demographic and ocular factors including age, sex, race, refractive error, and retinal and choroidal thicknesses. MAIN OUTCOME MEASURES: Association of SCS visibility and thickness with demographic and ocular factors. RESULTS: In healthy subjects (mean age 64.7, range 14-98 years), the choroidal-scleral junction was visible on EDI-OCT in 462 of 624 eyes (74%), among which a hyporeflective SCS layer could be discerned in 214 eyes (46%). The SCS layer was more likely to be present in older (P < 0.001) and White (P = 0.022) patients. In eyes with a detectable SCS layer, median (interquartile range) subfoveal SCS thickness was 34.8 (23.2-46.4) μm, and 32.8 (23.8-41.9) μm across the central macula. Both subfoveal and macular SCS thickness were higher with older age (P < 0.001), while subfoveal SCS thickness was also greater in White patients (P = 0.027). CONCLUSIONS: Suprachoroidal space anatomy varies with age and race. Understanding factors associated with SCS measurements could help inform future research focused on SCS-targeted therapies or patient selection in future clinical trials. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.