[A case of asymptomatic Dandy-Walker syndrome with cerebellar hemorrhage].

A case of asymptomatic Dandy-Walker syndrome (DWS) complicated by cerebellar hemorrhage is reported. A 65 year-old man was hospitalized for investigation and treatment of disturbance of consciousness. CT scan and MRI showed a large hematoma in the posterior fossa cyst. Postoperative CT scan and MRI revealed the DWS and cerebellar hemorrhage on the left side. This patient had no symptom until 65 years of age, in spite of having DWS. There has been no such case reported in the literature to our knowledge. Derangement of secretion and absorption of cerebrospinal fluid seem to have been the cause of late-onset symptoms after a long well balanced symptom-free period.