scholarly journals Synergistic enhancements of ultrasound image contrast with a combination of phase aberration correction and dual apodization with cross-correlation

2012 ◽  
Vol 59 (9) ◽  
Author(s):  
Junseob Shin ◽  
J. T. Yen
Keyword(s):  
Cross Correlation ◽  
Ultrasound Image ◽  
Image Contrast ◽  
Aberration Correction ◽  
Phase Aberration

scholarly journals A Locally Adaptive Phase Aberration Correction (LAPAC) Method for Synthetic Aperture Sequences

2018 ◽  
Vol 41 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Gustavo Chau ◽  
Marko Jakovljevic ◽  
Roberto Lavarello ◽  
Jeremy Dahl
Keyword(s):  
Speed Of Sound ◽  
Near Field ◽  
Ultrasound Image ◽  
Synthetic Aperture ◽  
Aberration Correction ◽  
Phase Aberration ◽  
Locally Adaptive ◽  
Diagnostic Capabilities ◽  
Screen Model

Phase aberration is a phenomenon caused by heterogeneity of the speed of sound in tissue, in which the actual speed of sound of the tissue is different than the assumed speed of sound used for beamforming. It reduces the quality and resolution of ultrasonic images and impairs clinical diagnostic capabilities. Although phase aberration correction (PAC) methods can reduce these detrimental effects, most practical implementations of PAC methods are based on the near field phase screen model, which have limited ability to represent the true aberration induced by inhomogeneous tissue. Accordingly, we propose a locally adaptive phase aberration correction (LAPAC) method that is applied through the use of synthetic aperture. The method is tested using full-wave simulations of models of human abdominal wall, experiments with tissue aberrators, and in vivo carotid images. LAPAC is compared with conventional phase aberration correction (cPAC) where aberration profiles are computed at a preselected depth and applied to the beamformer’s time delays. For all experiments, LAPAC shows an average of 1 to 2 dB higher contrast than cPAC, and enhancements of 3 to 7 dB with respect to the uncorrected cases. We conclude that LAPAC may be a viable option to enhance ultrasound image quality images even in the presence of clinically relevant aberrating conditions.

Performance Evaluation of Adaptive Imaging Based on Multiphase Apodization with Cross-correlation: A Pilot Study in Abdominal Ultrasound

2018 ◽  
Vol 40 (4) ◽  
pp. 195-214
Author(s):  
Junseob Shin ◽  
Yu Chen ◽  
Harshawn Malhi ◽  
Frank Chen ◽  
Jesse Yen
Keyword(s):  
Cross Correlation ◽  
Human Subjects ◽  
Vena Cava ◽  
Ultrasound Image ◽  
Abdominal Ultrasound ◽  
Image Contrast ◽  
Ultrasound Images ◽  
Adaptive Imaging ◽  
Weighting Matrix

Degradation of image contrast caused by phase aberration, off-axis clutter, and reverberation clutter remains one of the most important problems in abdominal ultrasound imaging. Multiphase apodization with cross-correlation (MPAX) is a novel beamforming technique that enhances ultrasound image contrast by adaptively suppressing unwanted acoustic clutter. MPAX employs multiple pairs of complementary sinusoidal phase apodizations to intentionally introduce grating lobes that can be used to derive a weighting matrix, which mostly preserves the on-axis signals from tissue but reduces acoustic clutter contributions when multiplied with the beamformed radio-frequency (RF) signals. In this paper, in vivo performance of the MPAX technique was evaluated in abdominal ultrasound using data sets obtained from 10 human subjects referred for abdominal ultrasound at the USC Keck School of Medicine. Improvement in image contrast was quantified, first, by the contrast-to-noise ratio (CNR) and, second, by the rating of two experienced radiologists. The MPAX technique was evaluated for longitudinal and transverse views of the abdominal aorta, the inferior vena cava, the gallbladder, and the portal vein. Our in vivo results and analyses demonstrate the feasibility of the MPAX technique in enhancing image contrast in abdominal ultrasound and show potential for creating high contrast ultrasound images with improved target detectability and diagnostic confidence.

Sign in / Sign up

Export Citation Format

Share Document