Volumetric Ultrasound Imaging With a Sparse Matrix Array and Integrated Fiber-Optic Sensing for Robust Needle Tracking in Interventional Procedures

Objective: Accurate visualization of interventional devices, such as medical needles, in relation to the procedural target is critical for the safe and effective guidance of interventional procedures. Ultrasound (US) imaging is widely used for guiding percutaneous needle interventions, but the 2D nature of most clinical US probes limits accurate 3D localization, particularly of the needle tip. In this work, we introduce a novel system that combines both volumetric US imaging and 3D needle tracking. Method: The proposed novel system integrates a fiber-optic hydrophone (FOH) into the needle and employs a 2D sparse spiral US array with 256 active elements. Real-time volumetric US imaging was achieved by plane-wave imaging with the sparse array, while 3D needle tip tracking was enabled through communications between the US probe and the FOH. Results: The system achieved spatial resolutions (mean ± standard deviation) of 2.06 ± 0.29mm (lateral), 2.26 ± 0.23mm (elevational), and 0.69 ± 0.12mm (axial) at depths ranging from 10 to 40mm. The tracking accuracy was better than 0.30 ± 0.21mm. The clinical potential of the system was demonstrated using a nerve block training phantom. Conclusions: This study presents a proof-of-concept for an integrated solution that enables simultaneous volumetric anatomical imaging and precise 3D needle tip tracking. Significance: The proposed system holds strong potential to enhance the efficacy and safety of image-guided interventional procedures by providing real-time 3D anatomical visualization and accurate needle tracking.