[A case of the traumatic hydrocephalus after large craniectomy for acute subdural hematoma].

Decompressive craniectomy sometimes causes neurological deficits known as 'the syndrome of the sinking skin flap' or 'the symptom of the trephined'. These disorders can be corrected with cranioplasty, but there is no consensus on appropriate treatments. We report a case of successful correction of traumatic hydrocephalus following craniotomy. A 50-year-old man was admitted to our hospital with disturbance of consciousness after a head injury. Decompressive craniectomy was performed for a right acute subdural hematoma. His consciousness recovered after the operation, but then deteriorated gradually and left hemiparesis occurred. CT scan revealed midline shift from right to left. These symptoms and CT findings were not improved after cranioplasty, but were improved with removal of the CSF from the adhered subarachnoid space. The diagnosis was traumatic hydrocephalus, and a cisternoperitoneal shunt was subsequently placed. We report this case to emphasize the necessity for study of CSF circulation, as well as the importance of examination of CBF and ICP after craniectomy.