Susac syndrome is characterized by the combination of dysfunction of the central nervous system with occlusion of the sides of the retinal artery (BRAO) and sensory-neural severity (SNHL).
The average age of onset is 32 years, with women being about 3.5 times more affected than males. At the onset of the disease, all three key symptoms are very rare. The syndrome is often initiated by constant headaches or migraines. Signs of an encephalopathy are confusion, loss of memory, loss of orientation, abnormal behavior, psychosis, and personality changes. Strokes of the CNS are manifested by ataxia, dysarthria, motor and sensory disturbances, and ocular muscle abnormalities.
The involvement of the eyes results in scotoma and distorted vision. Loss of hearing, which usually manifests itself in low to medium frequencies, is often accompanied by drastic tinnitus and dizziness. Partially, myalgia, arthralgia and dysfunction of the urinary tract also contribute to the condition.
There are three different forms depending on the clinical course: monocyclic, polycyclic and chronic permanent. The first form is self-limiting and ends after a maximum of two years. It fluctuates strongly. The second form recurs in a period of about two years.
Although the cause is unknown, the disease is thought to be caused by an autoimmune process involving inflammation and occlusion of the precapillary arterioles in the brain, retina and inner ear.