Wireless, Real-Time Plane-Wave Coherent Compounding on an iPhone: A Feasibility Study

The processing power in commercially available hand-held devices has improved dramatically in recent years. In parallel, techniques used in high-frame-rate medical ultrasound imaging, especially plane-wave (PW) imaging, have reduced the number of ultrasound transmissions and amount of data necessary to reconstruct an ultrasound image. In combination, the processing power and data reduction allow all of the processing steps in ultrasound image formation, from raw ultrasound channel data to final rendering, to be performed on a hand-held device. In this study, we send the raw ultrasound channel data from a research scanner wirelessly to an off-the-shelf hand-held device. The hand-held unit's graphical processing unit is processing the raw ultrasound data into the final image, achieving real-time frame rates on the order of 60-90 frames per second (FPS) for a single-angle PW transmission. Higher quality images are achieved by trading off frame rate by coherently compounding multiple PW images, resulting in frame rates on the order of, e.g., 13 FPS when coherently compounding 7 PW transmissions. The presented setup has the potential of providing image quality which could be valuable for simple medical ultrasound diagnostic scans of, e.g., the carotid artery or thyroid. Also, since the computationally expensive beamforming can be done in off-the-shelf devices, this could reduce the price of hand-held ultrasound systems in the future.