Characteristics of the various CSF shunt systems

Emergency department management of ventriculoperitoneal cerebrospinal fluid shunts

Emergency physicians must be familiar with VP shunts in order to recognize critical complications associated with these devices. Knowledge of the major types of shunt devices commonly used and the mechanics of those devices allows emergency physicians to evaluate patients with shunts in an orderly manner.

In vitro evaluation of CSF shunt function by radionuclides

An in vitro study of clearance of a radiolabeled marker was conducted on nine commonly used shunting devices. Clearance of 0.5 ml of 113mIn-diethylenetriamine-pentaacetic acid (DTPA) injected into the chamber, by water infused through the system at constant rate (0.034-0.46 ml/min), was measured by monitoring activity over the chamber and accumulating counts at 5-s intervals on a multichannel analyzer. Each flow rate was triplicated, and a graph of log value of counts versus time made. A mean t1/2 was computed for each flow rate and a new graph constructed. A best-fit curve constructed for the graph of each shunt system allows determination of flow rate for a known half time of isotope clearance.

A longitudinal study of shunt function in 360 patients with hydrocephalus

Data from an eight-year clinical study of shunt-treated hydrocephalus indicated continued shunt dependency in 289 of 360 patients. 919 combined pressure-radionuclide clearance studies were performed. In 307 studies in which the shunt was identified as nonfunctional, 208 patients were symptomatic for increased intracranial pressure and had the shunt revised. Of the other 99 patients, 71 have remained asymptomatic for three to 60 months (mean 27 months) and 28 subsequently required shunt revision after one to 67 months (mean 24 months). Five other clinical patterns are described. Various methods of monitoring shunt function are recommended.