An Open Source Realtime GPU Beamformer for Row-Column and Top Orthogonal to Bottom Electrode (TOBE) Arrays

Research ultrasound platforms have enabled many next-generation imaging sequences but have lacked realtime navigation capabilities for emerging 2D arrays such as row-column arrays (RCAs). We present an open-source, GPU-accelerated reconstruction and rendering software suite integrated with a programmable ultrasound platform and novel electrostrictive Top-Orthogonal-to-Bottom-Electrode (TOBE) arrays. The system supports advanced real-time modes, including cross-plane aperture-encoded synthetic-aperture imaging and aperture-encoded volumetric scanning. TOBE-enabled methods demonstrate improved image quality and expanded field of view compared with conventional RCA techniques. The software implements beamforming and rendering kernels using OpenGL compute shaders and is designed for maximum data throughput helping to minimize stalls and latency. Accompanying sample datasets and example scripts for offline reconstruction are provided to facilitate external testing.

Hadamard Encoded Row Column Ultrasonic Expansive Scanning (HERCULES) with Bias-Switchable Row-Column Arrays

Top-Orthogonal-to-Bottom-Electrode (TOBE) arrays, also known as bias-switchable row-column arrays (RCAs), allow for imaging techniques otherwise impossible for non-bias-switachable RCAs. Hadamard Encoded Row Column Ultrasonic Expansive Scanning (HERCULES) is a novel imaging technique that allows for expansive 3D scanning by transmitting plane or cylindrical wavefronts and receiving using Hadamard-Encoded-Read-Out (HERO) to perform beamforming on what is effectively a full 2D synthetic receive aperture. This allows imaging beyond the shadow of the aperture of the RCA array, potentially allows for whole organ imaging and 3D visualization of tissue morphology. It additionally enables view large volumes through limited windows. In this work we demonstrated with simulation that we are able to image at comparable resolution to existing RCA imaging methods at hundreds of frames per second. We validated these simulations by demonstrating an experimental implementation of HERCULES using a custom fabricated TOBE array, custom biasing electronics, and a research ultrasound system. Furthermore, we assess our imaging capabilities by imaging a commercial phantom, and comparing our results to those taken with traditional RCA imaging methods. Finally, we verified our ability to image real tissue by imaging a xenograft mouse model.