Structural and Functional Correlations in Sickle Cell Maculopathy: A Microperimetry and OCT-Angiography Analysis

Abstract

Purpose : To delineate the relationship between retinal vascular density, retinal thinning, and functional sensitivity in patients with sickle cell disease (SCD).

Methods : A single-site, cross-sectional, observational study was conducted with 27 patients diagnosed with sickle cell maculopathy at the Brent Sickle Centre, London, UK. Participants underwent swept source OCT and OCT-Angiography (Triton, Topcon Healthcare, Japan) to assess retinal structure and vessel density, coupled with microperimetry to evaluate retinal sensitivity. A custom application analysed OCT-A scans to locate the anatomical fovea, guiding perimetric test coordinates (Figure 1). Linear mixed-effect models predicted the impact of structural and vascular parameters on retinal sensitivity. Significant changes in the goodness of fit were determined with a likelihood-ratio test (LRT). Fixed effect predictions were used to calculate R^2.

Results : There was a significant relationship between structural parameters (inner retinal thickness [IRT] and vessel density from OCT-A) and retinal sensitivity (p < 0.0001). Figure 2 shows that models incorporating both IRT and OCT-A data, provided better sensitivity prediction (R^2 = 0.48) than those using either IRT or OCT-A alone (R^2 = 0.39 or 0.22, respectively). All differences in R^2 between models were statistically significant (LRT p < 0.001).

Conclusions : This study highlights the use of a structurally aligned perimetric test to standardise performance of microperimetry and improve the spatial structure-function correspondence. We demonstrate the importance of including OCT-angiography in predicting functional impact in sickle cell maculopathy.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.