Purpose: To correlate macular findings on spectral domain optical coherence tomography (SDOCT) and optical coherence tomography angiography (OCTA) with quantitative ischemic index calculations on ultra-wide-field fluorescein angiography (UWFFA) in patients with sickle cell retinopathy.
Methods: In this retrospective case series, SDOCT, OCTA, and UWFFA images of patients with sickle cell retinopathy were evaluated. Eyes were staged based on the Goldberg classification of proliferative sickle cell retinopathy. Focal areas of macular thinning were assessed on SDOCT, macular vessel density was derived from OCTA, and peripheral ischemic index was calculated from UWFFA.
Results: Eighteen eyes of 10 patients were included. Mean age was 36.8 ± 16.8 years, and 6 patients (11 eyes) were SS, 3 patients (5 eyes) were SC, and 1 patient (2 eyes) was Sβ thalassemia in hemoglobin electrophoresis. Abnormal macular findings included inner retinal atrophy in 11 eyes (61%) on SDOCT, vascular remodeling and nonperfusion in the superficial and deep retinal capillary plexus in 12 eyes (67%) on OCTA, and macular microvascular abnormalities in 9 eyes (50%) on UWFFA. Sickle cell retinopathy Stage I was identified in 4 eyes (22.2%), Stage II in 8 eyes (44.4%), and Stage III in 6 eyes (33.3%). Mean ischemic index was 14.1 ± 9.1%. Ischemic index was significantly correlated with hemoglobinopathy subtype (23.7 ± 9.8%, 9.3 ± 5.4%, and 16.3 ± 3.2%, for SC, SS, and Sβ thalassemia disease, respectively), stage of sickle cell retinopathy (22.5 ± 9.2%, 12.5 ± 4.9%, and 4.5 ± 0.73% for Stages III, II, and I, respectively), and presence of retinal thinning on SDOCT (17.4 ± 9.7% vs. 8.8 ± 5.1%, respectively).
Conclusion: Multimodal imaging can provide a more complete description of the microvascular and structural alterations associated with sickle retinopathy. The correlation between the severity of peripheral nonperfusion and stage and subtype of retinopathy suggests that UWF imaging may be a useful tool in the evaluation of these patients.