Management of proximal shunt obstruction. Technical note.

Proximal shunt obstruction or obstruction of the ventricular catheter may present with signs and symptoms of shunt failure with either no cerebrospinal fluid flow or a falsely low intracranial pressure (ICP) upon shunt tap. The author reports a technique for lowering the ICP and for measuring the pressure in patients with such obstruction by cannulation of the reservoir and ventricular catheter to penetrate into the ventricle with a 3 1/2-in. No. 22 spinal needle. The findings in 20 cases in which this approach was utilized are summarized.