Polyimide-Based Conformal Ultrasound Transducer Array for Needle Guidance

A conformal ultrasound imaging system has been developed that may potentially decrease the user variability associated with operation of rigid transducer-based medical ultrasound systems. Conformal transducer arrays were built and characterized, featuring bulk piezoelectric elements mounted on an array of silicon islands, connected with flexible polyimide joints. The joints successfully supported electrodes while bending, and were sufficiently soft to enable both conformation to body surfaces and needle insertion for ultrasound guidance procedures. A signal-to-noise ratio (SNR) of 39 dB was achieved from a needle target in a soft tissue phantom. A space–time backward propagation image reconstruction algorithm was simulated to demonstrate needle detection using a conformal transducer with an arbitrary array architecture.