title: Quadratic B-mode (QB-Mode) Ultrasonic Imaging with Coded Transmit Waveforms.
abstract: In this paper, the use of coded transmit waveforms with post-beamforming nonlinear filtering of echo data in diagnostic ultrasound is presented. The nonlinear filter based on the second-order Volterra filter (SoVF) model separates the linear and quadratic echo components. The grayscale representation of the latter results in a new mode of imaging we refer to as quadratic B-mode (QB-mode). The use of chirp transmit waveforms in imaging contrast agents allows for nonlinear excitation of microbubble contrast agents (UCA) at a range of frequencies throughout the bandwidth of the transducer. The QB-mode image is shown to produce significant increase in UCA contrast over standard B-mode images from conventional and chirp excitation with and without compression. This contrast enhancement is achieved without loss in spatial resolution.
authors.affiliation: Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455.
authors.forename: Daniele
authors.initials: D
authors.lastname: Cecchini
authors.forename: Hui
authors.initials: H
authors.lastname: Yao
authors.forename: Pornchai
authors.initials: P
authors.lastname: Phukpattaranont
authors.forename: Emad
authors.initials: E
authors.lastname: Ebbini