Continuous measurement of cerebral water content by time domain reflectometry

Continuous measurement of cerebral water content would be valuable for monitoring the progression and severity of brain edema, but existing methods cannot accurately quantify cerebral water content over prolonged periods of time. This paper proposes a time domain analysis of Time Domain Reflectometty (IDR) pulses to overcome the problem of timing drift which prevents the use of TDR for continuous measurements. Experiments done with canine cerebral tissue show that the proposed analysis more precisely quantifies water content than a TDR frequency domain analysis. Therefore, the IDR time domain analysis makes possible the continuous monitoring of cerebral water content.