Susac's Syndrome (SS) is a rare disease with unknown aetiology due to a microangiopathy affecting the precapillary arterioles of the brain, retina, cochlea and semicircular canals. Neurological manifestations, visual dysfunction and hearing loss represent the classical clinical triad of SS. Diagnosis is confirmed by laboratory investigations, neuroimaging findings, fluoroangiography and inner-ear studies. An early treatment with steroids and immunosuppressors limits the sequelae of disease. We report a case of SS in which the clinical triad occurred in a very short period of time. Brain MRI showed the involvement of cerebellum, this representing a rare neuroradiological finding in SS. A full remission of disease was obtained by using corticosteroids and cyclophosphamide in the acute-subacute phase and methotrexate as maintenance therapy. This latter has never been used before in SS.