A 54-year-old man had a 12 month history of weakness of both lower limbs with urge urinary incontinence, 6 month history of visual loss and hearing impairment and a 1 month history of cognitive dysfunction. He had no constitutional symptoms. On examination, his visual acuity was reduced to perception of light only in both eyes; funduscopy identified branch retinal artery occlusion (figure 1). He had spastic weakness and hyperreflexia in the lower limbs. Pure-tone audiometry suggested severe sensorineural hearing loss. MR scan of the brain showed characteristic features of Susac’s syndrome (figure 2). Following high-dose methylprednisolone pulses, intravenous immunoglobulin and rituximab, he made a partial clinical and radiological recovery.
Susac’s syndrome is rare with only around 300 cases reported worldwide. Its cause is unknown but it affects the microvasculature of the cochlea, retina and brain, leading to infarcts in each of these organs. The key to…