✓ After shunting, 43 patients with normal-pressure hydrocephalus were followed for 6 to 30 months. All patients had complete preoperative clinical evaluations, pneumoencephalograms, and isotope cisternography; in addition, 21 had saline infusion studies, and 15 had biopsies. Of the 10 patients in whom the etiology of the hydrocephalus was known eight (80%) were significantly improved. Of the other 33 patients, 21 (64%) showed some improvement; this was substantial and sustained in only eight (24%). The whole series of patients with idiopathic normal pressure hydrocephalus was divided into two groups on the basis of shunt response and the relative predictive values of preoperative tests. No significant association was found between the results of shunting and preoperative clinical factors, pneumoencephalography, isotope cisternography, saline infusion tests, or various combinations of clinical and laboratory abnormalities. The significance of these findings is discussed.
Stein et al. (1974) studied this question.