Demonstration of membranous aqueduct occlusion by fast multiphase magnetic resonance imaging.

Membranous aqueduct occlusion is one of the few causes of obstructive hydrocephalus that is amenable to direct surgical treatment. Conventional diagnostic methods may not delineate this entity. The advent of dynamic fast multiphase magnetic resonance imaging has improved the definition of the aqueductal membrane by enabling visualization of the obstructed cerebrospinal fluid flow within the ventricular system. We report a case of a 10-year-old boy in whom the diagnosis of membranous aqueduct occlusion was only achieved utilizing this new technique.