Coherent multi-transducer ultrasound imaging in the presence of aberration

TY - CHAP

T1 - Coherent multi-transducer ultrasound imaging in the presence of aberration

AU - Peralta , Laura

AU - Gomez , Alberto

AU - Hajnal, Joseph Vilmos

AU - Eckersley, Robert

PY - 2019/2/16

Y1 - 2019/2/16

N2 - In order to improve resolution, transducers with larger aperture size are desirable in ultrasound imaging. However, the practical aperture size is limited. Inhomogeneities and aberrating layers cause phase errors restricting the improvements provided by large arrays. Recently, we have shown the feasibility of a fully coherent multitransducer ultrasound imaging system (CMTUS), formed by several ultrasound transducers that are synchronized and freely located in space. The transducer locations along with the average speed of sound in the medium are deduced by maximizing the coherence between backscattered echoes from targeted point-like scattereres in the common field of view of the transducers. An improved image is obtained through coherent combination of the multiple transducers acting as a single larger effective aperture. In this study, the behavior of CMTUS in the presence of aberration is further investigated with simulations. A parametric study is presented, in which the geometry of the system, defined by two linear arrays, and the presence of acoustic clutter are investigated. In this framework, typical image quality metrics - resolution, contrast and contrast-to-noise ratio - are evaluated. Results suggest that the imaging enhancement made by the CMTUS is limited by the location of the transducers in space. Based on image metrics, an optimal spatial location is proposed for a CMTUS formed by two linear arrays. In addition, results show that, in the presence of clutter, image quality diminishes at larger aperture sizes. Nevertheless, CMTUS successfully corrects the aberration effects, without degrading the gains made by the large effective aperture.

AB - In order to improve resolution, transducers with larger aperture size are desirable in ultrasound imaging. However, the practical aperture size is limited. Inhomogeneities and aberrating layers cause phase errors restricting the improvements provided by large arrays. Recently, we have shown the feasibility of a fully coherent multitransducer ultrasound imaging system (CMTUS), formed by several ultrasound transducers that are synchronized and freely located in space. The transducer locations along with the average speed of sound in the medium are deduced by maximizing the coherence between backscattered echoes from targeted point-like scattereres in the common field of view of the transducers. An improved image is obtained through coherent combination of the multiple transducers acting as a single larger effective aperture. In this study, the behavior of CMTUS in the presence of aberration is further investigated with simulations. A parametric study is presented, in which the geometry of the system, defined by two linear arrays, and the presence of acoustic clutter are investigated. In this framework, typical image quality metrics - resolution, contrast and contrast-to-noise ratio - are evaluated. Results suggest that the imaging enhancement made by the CMTUS is limited by the location of the transducers in space. Based on image metrics, an optimal spatial location is proposed for a CMTUS formed by two linear arrays. In addition, results show that, in the presence of clutter, image quality diminishes at larger aperture sizes. Nevertheless, CMTUS successfully corrects the aberration effects, without degrading the gains made by the large effective aperture.

KW - Aberration

KW - Beamforming

KW - Large aperture

KW - Multi-transducers

KW - Resolution

KW - Ultrasound imaging

UR - http://www.scopus.com/inward/record.url?scp=85066603690&partnerID=8YFLogxK

U2 - 10.1117/12.2511776

DO - 10.1117/12.2511776

M3 - Conference paper

AN - SCOPUS:85066603690

VL - 10955

BT - Medical Imaging 2019

A2 - Byram, Brett C.

A2 - Ruiter, Nicole V.

PB - SPIE

T2 - Medical Imaging 2019: Ultrasonic Imaging and Tomography

Y2 - 17 February 2019 through 18 February 2019

ER -