Periventricular Water Content

Abstract

VARIOUS studies on dogs,¹cats,²and rabbits³have demonstrated that the total water content of normal adult brain is in the vicinity of 80%, with gray matter having a somewhat higher and white matter some-what lower content. Several investigators, using a number of different techniques, have estimated the size of the extracellular space of the brain.^4,5Currently, general agreement exists that the inulin space, as representative of the extracellular space, is approximately 7% to 20% of the normal cerebrum.^4-6 Alterations of water content in the periventricular white matter have been shown by Fishman and Greer.⁷They demonstrated an increased water content in experimental hydrocephalus. (We define hydrocephalus as the enlargement of the ventricular system associated, at least at some point of its history, with increased intracranial pressure.) In those studies, however, no attempt was made to determine the source or compartmentation of