Measurements of ventricular size in rats with mild, moderate and severe ventriculomegaly. a: Photographs of fixed brain samples of controls and rats with different degrees of ventriculomegaly. b: Histogram of mean ventricular size in the different groups of hydrocephalic rats. (data are means ± SEM; *** p<0.001 vs control). (c) Graph showing the inverse correlation between the ventricular diameter and thickness of the cortical mantle (slope = −1.388 ± 0.2296, r2 = 0.5664, p<0.001). Ventriculomegaly is associated with progressive thinning of the cortical mantle.