Susac syndrome

Objective: The objective of this study was to describe the clinical manifestations; radiographic, audiometric, and retinal fluorescein angiography findings; pathogenesis and treatment of Susac syndrome with review of the literature. Study Design: We conducted a retrospective case review. Setting: This study was conducted at a tertiary referral center. Patient: A 50-year-old woman presented with recurrent episodes of neurologic symptoms, bilateral sensorineural hearing loss, and silent retinal artery occlusion. Interventions: The patient underwent complete evaluation, including magnetic resonance image studies, audiometric tests, and retinal fluorescein angiography. She was treated initially with corticosteroids and later with other immunosuppressive agents. Results: The patient was initially diagnosed with left sudden sensorineural hearing loss. Despite comprehensive clinical and laboratory studies that did not reveal systemic disease, 3 weeks later, the patient developed vertigo, sensorineural hearing loss, and tinnitus in the opposite ear. The neurologic involvement and the bilateral audiologic manifestations raised the possibility of Susac syndrome. Conclusion: Susac syndrome is a rare disorder of unknown origin characterized by the triad of encephalopathy, fluctuating hearing loss, and visual loss resulting from microangiopathy of the brain, cochlea, and retina. The multiple organ involvement seen in Susac syndrome raises a differential diagnosis ranging from autoimmune disease, through systemic vasculitis, to multiple sclerosis. Otolaryngologists should be aware of this syndrome as a result of the vestibulocochlear manifestations and the multidisciplinary evaluation that is required.