Susac's syndrome is a rare idiopathic microangiopathy affecting the precapillary arterioles of the brain, retina and cochlea leading to the clinical triad of encephalopathy, retinopathy and hearing loss. The objective of this study is to describe a new case of Susac's syndrome reactivated after a 12-year period with a good response to immunosuppressive therapy. The patient was a 32-year-old woman, complaining of diplopia, right blurred vision, progressive gait disturbance, tinnitus, attention deficit, and slight memory loss. The patient was diagnosed as having Susac's syndrome and discharged with steroid therapy. After a 12-year period of clinical stability she had a relapse. Immunosuppressive therapy resulted in significant clinical and radiological improvement. Early clinical identification of Susac's syndrome is crucial for the initiation of immunosuppressive therapy and differential diagnosis. In our case, the combined use of corticosteroids and azathioprine was key in the relapse management.