Indications for Endoscopic Third Ventriculostomy in Normal Pressure Hydrocephalus

Abstract

Controversies remain regarding the proper diagnostic studies and prediction of outcome in patients with normal pressure hydrocephalus (NPH), and their management remains controversial. We propose a preoperative assessment routine the aim of which is to correctly select NPH patients, and to differentiate between them in terms of surgical treatment, identifying probable endoscopic third ventriculostomy (ETV) responders. We prospectively considered a group of 44 patients with suspected NPH on the basis of clinical symptoms and neuroradiological evidence, who have undergone supplemental diagnostic testing (tap test, external lumbar drainage, cerebrospinal fluid outflow resistance [Rout] determination through lumbar and ventricular infusion test). All 44 of these patients were treated with either shunt procedures or ETV. To choose the kind of treatment (shunt or ETV), we evaluated the individual response during infusion tests. The efficacy of both surgical techniques was approximately 70%, with a significantly lower complication rate for ETV. We evaluated the correlation between the various tests and the postoperative outcomes both for shunting and for ETV. Rout proved useful for preoperative assessment and choice of treatment. In carefully selected patients, ETV had qualitative results similar to shunting, presenting significantly fewer complications.