Abstract
Purpose :
The clinical utility of Optical Coherence Tomography Angiography (OCTA) in diagnosing and monitoring Sickle Cell Retinopathy (SCR) is not fully established. However, preliminary evidence suggests that OCTA could be more sensitive to microvascular retinal changes predictive of macular ischaemia, auto-infarction, and treatment response than existing imaging techniques. This prospective cross-sectional study aimed to determine the relationship between quantitive OCTA parameters and established indicators of macular ischaemia in SCR.
Methods :
30x15 Widefield OCTA scans of the temporal parafovea (Spectralis HROCT, Heidelberg Engineering), Widefield fundus photography, spectral-domain optical coherence tomography (SDOCT), and clinical assessment data such as LogMAR visual acuity and slit lamp examination findings were collected for patients with SCR and age-matched controls. For OCTA analysis, the fractal dimension and vascular density of the superficial and deep capillary plexuses were automatically assessed using vessel segmentation software. Independent T-tests compared quantitative OCTA metrics in SCR patients and controls. Multivariate logistic regression analysis studied the relationship between quantitive OCTA metrics, population characteristics, clinical assessment data, Goldberg staging and temporal parafoveal thickness on SDOCT. SPSS statistics Software IBM®Version 27 was used for data management.
Results :
45 eyes of 23 patients with SCR were evaluated: 16 with HBSS and 7 with HBSC.The mean(SD) age was 34(5) years. The control group consisted of 8 eyes of 4 patients with a mean(SD) age of 31(10) years. The density and fractal dimension of vessels in the superficial and deep capillary plexuses were significantly lower in those with SCR than in controls(P< .01). A significant positive relationship was found between LogMAR visual acuity, temporal para-foveal thickness and mean superficial capillary plexus density. In contrast, a significant negative relationship was found between age, HBSC genotype and superficial and deep plexus density(P< .01).
Conclusions :
We present a quantitative analysis of 45 OCTA scans from a cohort of 23 patients with Sickle Cell Disease.Widefield OCTA quantitative analysis successfully detected significant differences in the retinal microvasculature between SCR patients and controls.OCTA parameters were significantly associated with clinical indicators of macular ischaemia in our cohort.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.