Title :
Shearwave dispersion ultrasound vibrometry (SDUV) for measuring tissue elasticity and viscosity
Author :
Chen, Shigao ; Urban, Matthew W. ; Pislaru, Cristina ; Kinnick, Randall ; Zheng, Yi ; Yao, Aiping ; Greenleaf, James F.
Author_Institution :
Coll. of Med., Dept. of Physiol. & Biomed. Eng., Mayo Clinic, Rochester, MN
fDate :
1/1/2009 12:00:00 AM
Abstract :
Characterization of tissue elasticity (stiffness) and viscosity has important medical applications because these properties are closely related to pathological changes. Quantitative measurement is more suitable than qualitative measurement (i.e., mapping with a relative scale) of tissue viscoelasticity for diagnosis of diffuse diseases where abnormality is not confined to a local region and there is no normal background tissue to provide contrast. Shearwave dispersion ultrasound vibrometry (SDUV) uses shear wave propagation speed measured in tissue at multiple frequencies (typically in the range of hundreds of Hertz) to solve quantitatively for both tissue elasticity and viscosity. A shear wave is stimulated within the tissue by an ultrasound push beam and monitored by a separate ultrasound detect beam. The phase difference of the shear wave between 2 locations along its propagation path is used to calculate shear wave speed within the tissue. In vitro SDUV measurements along and across bovine striated muscle fibers show results of tissue elasticity and viscosity close to literature values. An intermittent pulse sequence is developed to allow one array transducer for both push and detect function. Feasibility of this pulse sequence is demonstrated by in vivo SDUV measurements in swine liver using a dual transducer prototype simulating the operation of a single array transducer.
Keywords :
biomechanics; biomedical ultrasonics; diseases; elastic waves; elasticity; patient diagnosis; viscoelasticity; viscosity; array transducer; diseases; patient diagnosis; shear wave propagation speed; shearwave dispersion ultrasound vibrometry; tissue elasticity; tissue viscoelasticity; tissue viscosity; ultrasound detect beam; ultrasound push beam; Biomedical equipment; Dispersion; Elasticity; Medical services; Pathology; Pulse measurements; Transducers; Ultrasonic imaging; Ultrasonic variables measurement; Viscosity; Algorithms; Animals; Cattle; Elasticity; Elasticity Imaging Techniques; Equipment Design; Feasibility Studies; Liver; Muscle, Striated; Swine; Transducers; Vibration; Viscosity;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
DOI :
10.1109/TUFFC.2009.1005