Hydrocephalus due to membranous obstruction of the fourth ventricle

Abstract

✓ Four patients with hydrocephalus due to membranous obstruction of the fourth ventricle are presented. This rare entity produced radiographic and clinical findings suggestive of posterior fossa tumor. Operative findings included normal cerebellar development and a translucent membrane just above the foramen of Magendie. Etiological possibilities are discussed.