ACTIVE SINGLING OUT OF SHUNT INDEPENDENCE

The availability of telemetric devices for intracranial pressure (ICP) measurements in line with a multipurpose valve (MPV) was shown to be the ideal condition for safe investigation of the problem of shunt ind ependence in 21 patients. After percutaneous closure of the shunt, all but 4 patients developed some degree of intracranial hypertension. Th e time lapse between blockade of the MPV and appearance of the morphol ogy, in the tracing, that suggests ICP is different for each patient a nd could reflect individual conditions such as the residual pathways o f CSF, ventricular size and complicance of the system.