[A case of hydrocephalus in follow-up of post-traumatic subdural effusion].

We report an interesting case of hydrocephalus following traumatic subdural effusion. A 50-year-old male was diagnosed as a traumatic subdural effusion. Three months later, he was transferred to our hospital again because of conscious disturbance and incontinence. Emergent CT showed characteristic hydrocephalus. The lateral ventricle and the third ventricle were remarkably enlarged. After Ventriculo-peritoneal shunt, the symptoms and radiographical findings were resolved. Both the compression of arachnoid villi around the superior saggital sinus and stenosis of the aqueduct by subdural effusion could be associated with the cause of hydrocephalus in this case.