Effects of Susac syndrome on the central vascular structure of the retina-An optical coherence tomography angiography study

Background: Susac syndrome (SS) describes an endotheliopathy of vessels in the central nervous system. Retinal involvement plays a central role in the manifestation of the disease. Objective: This case-control study investigated the macular microvasculature in patients with chronic SS compared to controls using optical coherence tomography angiography (OCTA). Material and methods: 12 eyes of 12 patients with SS were compared with age-matched healthy control subjects with regard to their OCT angiographic parameters. The flow density (FD) of different macular layers, foveal avascular zone (FAZ) parameters and central retinal thickness and volume values were compared between the two groups. Results: The FD of the choriocapillaris was reduced in Susac patients compared to healthy controls. The FD values of the superficial and deep capillary plexus of the inner retina, parameters of the FAZ as well as central retinal thickness and volume showed no significant differences between the two groups. Discussion: Treated chronic SS does not appear to significantly affect the vascular and structural composition of the central inner retina; however, differences in the choriocapillaris indicate changes in deeper, highly vascularized capillary layers.