ATYPICAL FOVEAL AND PARFOVEAL ABNORMALITIES IN SICKLE CELL DISEASE

Abstract

ABSTRACT Purpose: The primary aim was to describe patterns of para macular involvement, not yet reported but that OCT-A can now detect in SCD patients. The secondary aim was to search arguments concerning the physio pathogeny of para macular involvement. Methods: This institutional cohort retrospective study was conducted in a Referral Center for Ophthalmological Rare Diseases. Follow-up included an ophthalmological examination with optical coherent tomography and optical coherent tomography angiography. Results: Hundred and thirty-two sickle cell patients were included. Typical sickle cell maculopathy was observed in temporal area in 84 eyes (40.0 %) of SS patients and 8 eyes (14.8 %) of SC patients (p < 0.001). Enlargement of the foveal avascular zone was observed in 10 eyes whom 8 of SS patients. Two atypical parafoveal abnormalities were found in SS patients only. The first one consisted in macular thinning with normal vascularization in 15 eyes of 11 patients. The second atypical maculopathy was large areas of loss of vascularization without retina thinning 10 eyes of six patients. Multivariate analysis did not show a statistically significant relation between the PSR stage and the different type of sickle cell maculopathy (p = 0.21) Conclusion: Those atypical sickle cell maculopathy may correspond to early forms preceding a typical SCM. This would point towards several physiopathogenic mechanisms. The first one included the existence of ischemia which can be related to anemia. Presence of retinal thinning without vascular involvement point out to a neurogenic mechanism.