Ventriculoperitoneal shunt flow dependency on the number of patent holes in a ventricular catheter

Minimally invasive recanalization of obstructed ventricular catheters is a new treatment modality currently under investigation. It has been shown that blocked ventricular catheters can be at least partly reopened with ultrasonic cavitation, fiberoptic delivery of laser energy and electrocautery. it is not known, however, how many of the holes must be reopened in order to establish acceptable pressure-flow characteristics. In this study, the pressure-flow relationship of partially obstructed ventricular catheters was determined using experimental and electrical circuit/computer models. It has been demonstrated in all cases that an additional pressure of no more than 0.5 cm of water is generated when only a single 500-mu m-diameter hole in the ventricular catheter permits flow. Partial recanalization of a ventricular catheter provides acceptable CSF hydrodynamics. Copyright (C) 2000 S. Karger AG, Basel.