Abstract
Purpose :
Existing studies have proposed an association between obstructive sleep apnea (OSA) and central serous chorioretinopathy (CSC) and the effect of each disease individually on choroidal thickness (CT). These studies reported a below-average CT in OSA and an above-average CT in CSC. In the present study, we hypothesize that patients with OSA and CSC exhibit a unique CT when compared to patients with CSC or OSA alone, and that OSA treatment status and severity level are associated with measurable differences in CT.
Methods :
In an IRB-approved, retrospective observational study, we included all patients from the STAnford Research Repository (STARR) with diagnoses of CSC and/or OSA seen at the Byers Eye Institute at Stanford with high-quality spectral-domain optical coherence tomography (SD-OCT) imaging from 2011 to 2019. OCT analysis included CT measurements in each eye at five points (subfoveal; 1500- and 3000-microns nasal and temporal to fovea) by two independent and masked graders. ANOVA and Tukey tests were used to compare mean CT among patient groups.
Results :
A total of 64 patients met study inclusion criteria – 22 patients with CSC and OSA, and age- and sex-matched patients with only CSC (N=20) or only OSA (N=22). We found mean CT at all five measured points to be significantly greater in CSC patients with treated OSA compared to those with untreated OSA. We also found a significant positive correlation between subfoveal CT and Apnea-Hypopnea Index (AHI), a marker of OSA severity (p = 0.020). Although OSA treatment status and AHI severity demonstrated collinearity, they were independently significant in multivariate regression modelling (p=0.016, p=0.017, respectively). CT thickness grading reached an interclass correlation coefficient of 95% with a less than 10 mm difference for any given measurement.
Conclusions :
Choroidal thickness measured subfoveally and at 4 parafoveal points was significantly greater in patients with CSC and treated OSA compared to patients with CSC and untreated OSA. Treated OSA patients exhibited a CT similar to patients with only CSC, while untreated OSA patients exhibited a CT similar to patients with only OSA. Further work will be needed to elucidate the pathophysiologic underpinnings of these findings. If confirmed in larger patient populations, CT in CSC may be used to screen for potential undiagnosed or undertreated OSA.
This is a 2020 ARVO Annual Meeting abstract.