Susac's syndrome: an immune mediated endotheliopathy laden with challenges and controversies

Abstract

Susac's syndrome is a microangiopathy of the retina, inner ear and brain manifesting as a triad of encephalopathy, hearing loss and branch retinal artery occlusion. The pathological mechanism is thought to be an immune-mediated small vessel vasculitis with some pathophysiological similarity to dermatomyositis. Awareness and early recognition of this syndrome is important as early treatment with immunosuppression can minimise cognitive, audiological and visual sequelae. We report a case of a 33-year-old woman who presented with the characteristic syndrome. She was treated with immunomodulatory therapy and remains well 2 years postpresentation with no new events.

Figure 1

Fluorescein angiogram of retina showing the branch retinal artery occlusion.

Figure 2

(A) Sagittal fluid-attenuated inversion recovery (FLAIR), (B) axial FLAIR and (C and D) diffusion-weighted imaging (DWI): numerous callosal, hemispheric and posterior fossa white matter lesions. These are associated with several sites of acute small vessel ischaemic change as evidenced by restricted diffusion on the DWI.

Figure 3

Pure tone audiometry showing mild to moderate sensorineural hearing loss on the left and moderate to moderately-severe sensorineural hearing loss on the right.