Susac syndrome

Clinic

• Also called retino-cochleo-cerebral vasculopathy
• It is a very rare form of microangiopathy characterized by
  • Encephalopathy
  • Retinal artery occlusions
  • Hearing loss

• The cause is unknown but it is theorized that antibodies are produced against endothelial cells in tiny arteries which leads to damage and the symptoms related to the illness

Presentation

• Speech issues
• Intense headaches and migraines

• Hearing loss

• Impaired vision

Pathogenesis

In the March 1979 report in Neurology, Drs. Susac, Hardman and Selhorst reported two patients with the triad of encephalopathy, hearing loss and microangiopathy of the retina. The first patient underwent brain biopsy, which revealed sclerosis of the media and adventitia of small pial and cortical vessels, suggestive of a healed angiitis. Both patients underwent fluorescein retinal angiography that demonstrated multifocal retinal artery occlusions without evidence of embolic disease. Though the exact pathogenesis of this disorder is unknown, the retinal and brain biopsy findings suggest a small vessel vasculopathy leading to arteriolar occlusion and microinfarction of cerebral, retinal and cochlear tissue. Demyelination is not a typical feature of Susac's syndrome. Muscle biopsies from such patients are usually normal, but some have also shown nonspecific signs of inflammation such as dense hyaline material surrounding endomysial capillaries. This suggests a possible systemic component of this disease, despite the predominance of central nervous system features. The latest thinking is that an antibody directed against endothelial cells is the pathogenic mechanism in this disease which causes the microscopic strokes in the brain, retina, and inner ear.