Title :
Assessment of myocardial elastography performance using normal and ischemic phantoms undergoing physiological motion
Author :
Okrasinski, Stan ; Ramachandran, Bharat ; Konofagou, E.E.
Author_Institution :
Biomed. Eng. Dept., Columbia Univ., New York, NY, USA
Abstract :
Myocardial Elastography has been introduced as a non-invasive, ultrasound-based imaging, which can detect abnormalities in myocardial stiffness that cannot be detected with the current standard echocardiography used clinically. By acquiring radio-frequency (RF) frames at high frame rates (190-310 Hz), the deformation of the myocardium can be estimated, and used to identify regions of abnormal deformation indicative of ischemia. In this study, we pursue in vitro validation of ME using polyacrylamide phantoms. Phantoms of homogeneous stiffnesses and with stiff inclusions were imaged, and ME was applied. Rotational motion was mapped and distinguished from torsional motion. During expansion/contraction, if an inclusion was not present, the estimated strain patterns were smooth, while if an inclusion was present, abnormalities were observed which enabled identification of the inclusion. The average peak radial and circumferential strains were 2.1±0.3% and -2.0±1% for a normal phantom, and -0.07±0.9% and 0.3±0.6% for an ischemic phantom, respectively. This study shows ME to be capable of distinguishing between different types of motion configurations, and is sensitive to stiffness changes in tissue-mimicking phantoms.
Keywords :
biomechanics; deformation; echocardiography; elasticity; phantoms; ultrasonic imaging; circumferential strains; contraction; echocardiography; expansion; ischemic phantoms; myocardial deformation; myocardial elastography; myocardial stiffness; normal phantoms; physiological motion; polyacrylamide phantoms; radial strains; radiofrequency frames; rotational motion; tissue-mimicking phantoms; ultrasound-based imaging; Capacitive sensors; Cardiac disease; Cardiovascular diseases; Heart; Imaging phantoms; Mechanical factors; Motion detection; Myocardium; Radio frequency; Ultrasonic imaging;
Conference_Titel :
Bioengineering Conference, Proceedings of the 2010 IEEE 36th Annual Northeast
Conference_Location :
New York, NY
Print_ISBN :
978-1-4244-6879-9
DOI :
10.1109/NEBC.2010.5458147