Parallel tracking and other methods for real-time ARFI imaging systems
Acoustic Radiation Force Impulse (ARFI) imaging is a useful method for characterizing the local mechanical properties of tissue. Relevant issues in creating a real-time ARFI imaging system include patient exposure, oberservation time per image location, field-of-view, and data porting and processing. We propose two methods to increase ARFI frame rates without compromising patient safety. We have implemented ARFI imaging with parallel tracking and alternating receive foci in tissue mimicking phantoms. Parallel receive beamforming is used to simultaneously track multiple locations from a single pushing pulse. Alternating the lateral positions of receive foci on each tracking pulse can be used to observe the response of tissue over a larger region. These parallel techniques are demonstrated in a tissue mimicking phantoms using ratios of 4:1, 8:1, and 12:1. Displacement images using parallel tracking were compared to images created with conventional tracking. Images using the parallel tracking showed little difference to the images produced by conventional tracking after a short wait time. © 2006 IEEE.
