title: Viscoelastic properties of normal rat liver measured by ultrasound elastography: Comparison with oscillatory rheometry.
abstract: Ultrasound elastography has been widely used to measure liver stiffness. However, the accuracy of liver viscoelasticity obtained by ultrasound elastography has not been well established.
  
  
  
  To assess the accuracy of ultrasound elastography for measuring liver viscoelasticity and compare to conventional rheometry methods. In addition, to determine if combining these two methods could delineate the rheological behavior of liver over a wide range of frequencies.
  
  
  
  The phase velocities of shear waves were measured in livers over a frequency range from 100 to 400 Hz using the ultrasound elastography method of shearwave dispersion ultrasound vibrometry (SDUV), while the complex shear moduli were obtained by rheometry over a frequency range of 1 to 30 Hz. Three rheological models, Maxwell, Voigt, and Zener, were fit to the measured data obtained from the two separate methods and from the combination of the two methods.
  
  
  
  The elasticity measured by SDUV was in good agreement with that of rheometry. However, the viscosity measured by SDUV was significantly different from that of rheometry.
  
  
  
  The results indicate that the high frequency components of the dispersive data play a much more important role in determining the dispersive pattern or the viscous value than the low frequency components. It was found that the Maxwell model is not as appropriate as the Voigt and Zener models for describing the rheological behavior of liver.
authors.affiliation: School of Biomedical Engineering, Shenzhen University, Shenzhen, China.|National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen, China.|Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Shenzhen, China.
authors.forename: Haoming
authors.initials: H
authors.lastname: Lin
authors.affiliation: School of Biomedical Engineering, Shenzhen University, Shenzhen, China.|National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen, China.|Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Shenzhen, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Shen
authors.affiliation: School of Biomedical Engineering, Shenzhen University, Shenzhen, China.|National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen, China.|Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Shenzhen, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.affiliation: School of Biomedical Engineering, Shenzhen University, Shenzhen, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Electrical and Computer Engineering, St. Cloud State University, St. Cloud, MN, 56301, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: School of Biomedical Engineering, Shenzhen University, Shenzhen, China.|National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen, China.|Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Shenzhen, China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Biomedical Engineering, Shenzhen University, Shenzhen, China.
authors.forename: Yanrong
authors.initials: Y
authors.lastname: Guo
authors.affiliation: School of Biomedical Engineering, Shenzhen University, Shenzhen, China.|National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen, China.|Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Shenzhen, China.
authors.forename: Tianfu
authors.initials: T
authors.lastname: Wang
authors.affiliation: School of Biomedical Engineering, Shenzhen University, Shenzhen, China.|National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen, China.|Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Shenzhen, China.
authors.forename: Siping
authors.initials: S
authors.lastname: Chen
mesh_terms: D000818:Animals; D054459:Elasticity Imaging Techniques / Q000379:methods*; D008099:Liver / Q000254:growth & development*; D051381:Rats; D012212:Rheology; D014783:Viscosity
keywords: Viscoelasticity; dispersion; elastography; liver; rheometry; shearwave dispersion ultrasound vibrometry