Towards diagnostic flow measurement from a catheter tip pressure sensor

This paper reports the investigation of the additional ability of a catheter tip pressure sensor to measure flow rate. The sensor's ability to measure flow rate builds on an earlier development of temperature measurement from the pressure sensor. The flow rates of interest range from 0 to 30mL/hour, those expected through a hydrocephalus shunt. The feasibility of making flow measurements from the MEMS piezoresistive pressure sensor was assessed in terms of the sensor's repeatability, its potential resolution and its temporal response. Within the flow range 0 to 30 mL/hour the sensor has demonstrated the ability to resolve differences in flow rate of less than 5mL/hour. The sensor demonstrates high degree of repeatability with coefficient of variation of less than 5 % across all flow rates in the measurement range.