title: Methods for reverberation suppression utilizing dual frequency band imaging.
abstract: Reverberations impair the contrast resolution of diagnostic ultrasound images. Tissue harmonic imaging is a common method to reduce these artifacts, but does not remove all reverberations. Dual frequency band imaging (DBI), utilizing a low frequency pulse which manipulates propagation of the high frequency imaging pulse, has been proposed earlier for reverberation suppression. This article adds two different methods for reverberation suppression with DBI: the delay corrected subtraction (DCS) and the first order content weighting (FOCW) method. Both methods utilize the propagation delay of the imaging pulse of two transmissions with alternating manipulation pressure to extract information about its depth of first scattering. FOCW further utilizes this information to estimate the content of first order scattering in the received signal. Initial evaluation is presented where both methods are applied to simulated and in vivo data. Both methods yield visual and measurable substantial improvement in image contrast. Comparing DCS with FOCW, DCS produces sharper images and retains more details while FOCW achieves best suppression levels and, thus, highest image contrast. The measured improvement in contrast ranges from 8 to 27 dB for DCS and from 4 dB up to the dynamic range for FOCW.
authors: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, 7491 Trondheim, Norway. jochen.deibele@rwth-aachen.de
authors: Jochen M
authors: JM
authors: Rau
authors: Svein-Erik
authors: SE
authors: Måsøy
authors: Rune
authors: R
authors: Hansen
authors: Bjørn
authors: B
authors: Angelsen
authors: Thor Andreas
authors: TA
authors: Tangen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D009038:Motion; D017711:Nonlinear Dynamics; D019047:Phantoms, Imaging; D011237:Predictive Value of Tests; D011312:Pressure; D012542:Scattering, Radiation; D059629:Signal-To-Noise Ratio; D013016:Sound; D013997:Time Factors; D018084:Ultrasonography, Interventional / Q000295:instrumentation / Q000379:methods*; D014732:Vibration