Development of ultra miniature 1-french sensors for wireless radial arterial pressure monitoring

Miniaturized pressure sensors attached to catheters have numerous applications in the biomedical and life science fields including the monitoring of arterial, ventricular, intracranial and intraocular pressures. Recent advances in MEMS (microelectromechanical systems) technology and its associated fabrication processes, such as DRIE (deep reactive ion etching), have allowed for further miniaturization of these devices, expanding the application landscape to include small animal models and new human applications. One such human application is the wireless measurement of radial arterial blood pressure (BP). The goal of this research program is to produce a truly portable wireless radial arterial monitoring system using a custom-designed ultra-miniature pressure sensor appropriately sized to fit within the tip of a 1-French catheter (333 micron), so that convenient in-vivo measurements of BP are possible. The proposed system consists of two assemblies. The sensor, catheter, and wristband containing the battery and telemetry circuit form one assembly and the portable wireless PDA-sized transceiver module forms the other. This paper reports on the custom miniature MEMS pressure sensor developed for this application.