The neuropsychology of hydrocephalus.

The relationship between neuropsychological impairment and hydrocephalus is reviewed and three case studies presented. Current brain imaging technology provides a method for detailed quantification of ventricular expansion and alteration or loss of cortical tissue in hydrocephalus. However, there appears to be little systematic relationship between ventricular size in hydrocephalus and the type or degree of neuropsychological impairment. As a group, hydrocephalic patients do demonstrate a variety of cognitive and perceptual-motor deficits, but there does not appear to be a common diagnostic neuropsychological pattern in hydrocephalus although perceptual-motor/manipulo-spatial deficits appear to predominate. It appears that there is considerable neural plasticity that occurs in some patients with congenital hydrocephalus and much of this functional reorganization may take place at subcortical and subtentorial levels. Clinical guidelines for the neuropsychological assessment of hydrocephalus are given.