A 24-year-old man with a head injury developed a communicating hydrocephalus and underwent ventriculoperitoneal shunting. A revision was required, and the patient emerged from coma with severe behavior outbursts, which persisted for more than 1 year. Computed tomographic scans indicated a recurrence of low-pressure communicating hydrocephalus and a shunt revision was performed. The patient's severe behavior outbursts immediately decreased dramatically. The improvement continued long term and extended beyond the acute rehabilitation program.