 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.