Observation of the Ultrasonic Vibration Potential with an Instrumented Coaxial Needle Probe.

Stereotactic core biopsies typically use ultrasound imaging to locate tumours and guide a biopsy needle toward them. Due to the poor resolution of ultrasound images, oftentimes it is difficult to ensure that the needle reaches the target before the tissue is sampled resulting in false negatives. Sensor-instrumented needles provide an efficient way of characterizing the tissue at the needle tip to improve tumour targeting. A modality that has not been considered for real-time tissue characterization is the ultrasonic vibration potential (UVP) of the medium - a small electric signal generated within the tissue when subjected to ultrasonic pressure. The magnitude of the UVP depends on the electroacoustic properties of the tissue, providing valuable information about the relative tissue composition. This paper investigates, for the first time, the feasibility of measuring the ultrasonic vibration potential (UVP) of assorted media using an instrumented biopsy needle. The results show that the UVP can be effectively measured using the proposed instrumented needle providing electroacoustic data that can be used in future work for real-time tissue classification during stereotactic procedures.