OCTA macular parameters to predict Peripheral Retinopathy Severity in Sickle Cell Disease

PURPOSE: To explore correlation between microvascular changes in the macula as seen on optical coherence tomography angiography (OCTA) and peripheral retinal ischemia in patients with sickle cell disease. METHODS: 112 patients with SCD (112 eyes) and 45 age-matched unaffected controls (45 eyes) were included. SCD patients were divided into two groups: those with peripheral retinal ischemia (n=69) and those without (n=43). We analyzed foveal avascular zone (FAZ) parameters and perifoveal capillary density, and these metrics were correlated with the extent of peripheral ischemia. RESULTS: Patients with peripheral ischemia exhibited significantly larger FAZ areas and lower perifoveal capillary densities compared to both non-ischemic SCD patients and controls. These differences were most pronounced in the DCP. Notably, even SCD patients without detectable peripheral ischemia showed a trend toward reduced DCP density (p=0.04 vs. controls), suggesting early vulnerability of this plexus. The degree of FAZ enlargement and capillary dropout correlated strongly with the number of ischemic quadrants on angiography (r up to 0.52, p<0.001). Eyes with proliferative retinopathy had even more severe macular changes than those with non-proliferative ischemia. CONCLUSION: In SCD, macular microvascular alterations on OCTA are strongly related to the presence and severity of peripheral retinal ischemia.