A review and update on the ophthalmic implications of Susac syndrome

Susac syndrome is a rare condition presumed to be immune-mediated occlusion of small arterial vasculature principally of the brain, inner ear, and retina. Clinically, the syndrome manifests as a pathognomonic triad of encephalopathy, hearing loss, and branch retinal artery occlusion. Early recognition and diagnosis is important as delayed treatment may be profound and result in deafness, blindness, dementia, and other neurological deficits. The plethora of imaging technology, including magnetic resonance imaging, retinal fluorescein angiography, optical coherence tomography, and optical coherence tomography angiography, allows deeper and more discrete anatomical-physiological correlation of underlying pathology, early diagnosis, and imaging biomarkers for early detection of relapse during follow-up. We highlight the current clinical classification of Susac syndrome, available investigations, treatment, and care pathways.