Unexpected shunt-dependent hydrocephalus after unruptured aneurysm surgery-a case report.

A chronic hydrocephalus after unruptured aneurysm surgery is an extremely rare condition. Its etiology and pathophysiology are also unclear. We report a case of chronic hydrocephalus in a patient who underwent permanent shunt placement after unruptured aneurysm clipping surgery. A 65-year-old man developed chronic hydrocephalus requiring shunt placement after clipping surgery of left anterior cerebral artery aneurysm and right middle cerebral artery aneurysm. This case shows that chronic hydrocephalus is a possible complication of unruptured aneurysm surgery, which can be resolved with an appropriate shunt operation.