Novel approach for ultrafast ultrasound image formation in complex media: aberration correction and real-time speed-of-sound mapping

Ultrafast ultrasound imaging introduced plane waves to form high quality images at high frame rates. In complex media, wave front distortions still hinder severely the image quality and the quantitative assessments. We present here a novel and fast method for adaptive image formation, based on ultrafast coherence optimization.

Plane waves were transmitted with a programmable scanner, driving a 192-element linear probe, at central frequency of 6.25MHz. We proposed an approach based on Singular Value Decomposition of the beamformed images at each transmit angle. We demonstrated that the first angular singular vector gives the amplitude and phase aberration law in the plane wave basis. The first spatial singular vector provides a corrected image.

Angular and canonical aberrations were proven to be fully recovered by the SVD Beamforming approach both in simulation and in vitro. In vivo images of human liver, and mouse brain obtained through the skull, showed a remarkable improvement (+8dB). In addition, phase aberration knowledge allows to quantitatively compute sound speed mapping. Outstandingly, this method offers efficient adaptive and quantitative imaging at ultrafast frame rates; paving the way to transcranial ultrasound imaging at unprecedented temporal and spatial resolutions.