A non-invasive CSF flowmeter.
A new non-invasive method for quantitative measurement of cerebrospinal fluid (CSF) flow in the ventriculo-peritoneal shunt tubing, used in hydrocephalus, has been developed. It is an implantable device which produces a bubble in the shunt tubing by electrolysis. This bubble is then detected in the tubing by an electrode arrangement using electric impedance or ultrasonically using a Doppler probe. The energy for electrolysis is supplied by extracorporeal high-frequency transmission. The CSF flow rate is calculated by the velocity of bubble flow in the tubing. CSF flow rates, ranging from 0.01 to 1.00 ml/min, have been measured in animal experiments with statistically good accuracy. In 11 clinical cases a flow range of between 0.01 and 1.93 ml/min have been observed.
D000818:Animals; D001698:Biomedical Engineering; D002557:Cerebrospinal Fluid Shunts; D006801:Humans; D006849:Hydrocephalus / Q000134:cerebrospinal fluid* / Q000601:surgery; D008991:Monitoring, Physiologic; D012212:Rheology