Communicating hydrocephalus as a cause of aqueductal stenosis

Abstract

Eleven cases of presumed aqueductal stenosis with onset of symptoms after the 1st decade were reviewed. Ten patients had complete occlusion and 1 a high-grade stenosis. In 10, the dilated lateral ventricles caused a marked inferior displacement of the 3rd ventricle. Postshunting diagnostic studies on 6 of these patients revealed ascent of the 3rd ventricle, and in 3 of these the aqueduct was patent. It appears that in some cases of advanced communicating hydrocephalus the descending 3rd ventricle kinks or pinches shut the aqueduct, adding an obstructive component which accelerates the clinical picture. The mechanism and clinical features of this process are discussed.