Challenge: Develop the world's first totally implantable, long-term blood pressure monitoring sensor.
Concept: A flow-through, hemo-compatible, electrical resistance strain-gauge sensor with zero "dead volume".
Solution: A tubular, strain-gauge-based sensor was developed, fabricated and tested that demonstrated high accuracy with minimal disruption to the blood flow. Using a flow-through configuration with zero dead volume, changes to blood shear, blood flow interruption and blood flow separation were minimized. Computational Fluid Dynamics Analysis was used during the design of the blood flow path. The sensor used a novel proprietary thin-film process for depositing the strain gauge directly onto the sensor diaphragm, thus eliminating the need for adhesive bonds that negatively impact the performance of pressure sensors. Extensive Finite Element Analysis was used to find the optimal locations for depositing strain gauges on the outside surface of the diaphragm.