Third ventriculostomy in normal pressure hydrocephalus

Improvement in three out of four cases of normal pressure hydrocephalus aft er third ventriculostomy is reported. Pre- and postoperative ventricular pr essure recording suggested that this improvement may be occurring in the ab sence of an improvement in ventricular pressures. Third ventriculostomy may relieve periventricular tissue stress and thus improve local blood flow, w hich is a likely mechanism in the syndrome of normal pressure hydrocephalus .