The results obtained in 32 patients with obstruction of the cerebrospinal fluid circulation caused by cerebral tumors and inflammatory reactions of the leptomeninges or ventricular ependima, are presented. The results were satisfactory in 20 cases; 3 patients did not come back for follow-up and 9 died. All deaths occurred in the group of neoplasms, and only in one case this bad evolution was related to infectious complication of the ventriculo-venous shunt.