Membranous obstruction of the foramen of magendie: A case report, literature review and recommendations

Abstract

Hydrocephalus is a common condition characterized by disturbed cerebrospinal fluid dynamics with subsequent accumulation inside the cerebral ventricles. Fourth ventricle outlet obstruction (FVOO) is a type of noncommunicating tetraventricular hydrocephalus, frequently characterized by a disproportionately enlarged fourth ventricle. In children, FVOO has been linked to congenital malformations and inflammatory processes. In contrast, the pathophysiology remains unclear in adults in whom several etiologies have been described. Recent evidence suggests that FVOO is underdiagnosed; and to date, there are no clear guidelines regarding the diagnosis and treatment of this condition. In this article, we present the case of an adult woman who presented to us for chronic headache, nausea, vomiting, and gait disturbance, found to have an FVOO with a membrane overlying the foramen of Magendie. We also provide a literature review of adult cases of membranous FVOO, suggest a diagnostic approach to the condition, and finally conclude with a treatment algorithm for cases of disproportionately enlarged fourth ventricle. © 2021