Dynamic shunt testing applying short lasting pressure waves--inertia of shunt systems. Academic Article uri icon

Overview

abstract

  • Laboratory shunt testing often comprises only static pressure flow and flow pressure tests. We applied shorter acting pressure waves using a computerised shunt testing rig to investigate shunt behaviour under conditions that might occur in the clinical situation, e.g. during nocturnal vasogenic pressure waves or shorter rises in ICP at movements or exercise. Additionally the influence of a human-like compliance situation compared to a fixed pressure/volume relationship was investigated. Shunts behaved very differently than seen in static tests and demonstrated a marked inertia the shorter pressure waves acted. Although some valves opened at higher pressure, all valves showed marked hysteresis and none did close--if at all--at the specified pressure level. This behaviour might be a cause of shunt overdrainage not related to siphoning. The simulation of a human-like variable pressure-volume relationship with higher compliance at lower pressures had a positive effect on shunt function by decreasing the amount of drained volume. We therefore suggest to include dynamic pressure wave testing if hydrodynamic properties of shunts are to be evaluated.

publication date

  • January 1, 2002

Research

keywords

  • Cerebrospinal Fluid
  • Cerebrospinal Fluid Shunts
  • Intracranial Pressure

Identity

Scopus Document Identifier

  • 0035989066

Digital Object Identifier (DOI)

  • 10.1007/978-3-7091-6738-0_5

PubMed ID

  • 12168301

Additional Document Info

volume

  • 81