The long term goals of this research are to produce accurate, quantitative assessments of ultrasound scattering in vivo, to improve the noninvasive diagnostic capabilities of medical ultrasound. This research will center on the diagnosis and monitoring of diffuse liver disease with ultrasound and the detection and differentiation of focal lesions, especially when these are masked by diffuse disease conditions. The hypothesis is that quantitative backscatter images depicting backscatter levels and backscatter frequency dependence, as well as acoustic parameters derived from backscatter signals, including attenuation, scatterer size estimated from spatial auto correlation functions and scatterer number densities, will provide improved differentiation between normal and diseased conditions. Instrumentation will be adopted to expand the frequency range of liver backscatter estimates, and a data base on backscatter and attenuation coefficients for normal individuals will be expanded. Newly derived parameters for assessing scatterer size and number density will be further evaluated in phantoms, including novel ones constructed to model liver disease. When thoroughly understood, values for these parameters will be obtained for normal liver. Work will continue to measure backscatter, attenuation, and when available, scatterer size and number density in a large group of patients with diffuse liver disease. These studies will be extended to individuals with proven focal lesions in the liver, exploring new ways to acquire and display echo data. Finally, animals models for fatty infiltration in the liver, cirrhosis and steroid induced hepatophy will be used to further our understanding of acoustic changes accompanying liver disease.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA039224-14
Application #
2089760
Study Section
Diagnostic Radiology Study Section (RNM)
Project Start
1985-09-01
Project End
1997-04-30
Budget Start
1995-05-01
Budget End
1996-04-30
Support Year
14
Fiscal Year
1995
Total Cost
Indirect Cost
Name
University of Wisconsin Madison
Department
Physics
Type
Schools of Medicine
DUNS #
161202122
City
Madison
State
WI
Country
United States
Zip Code
53715
Techavipoo, U; Varghese, T; Chen, Q et al. (2004) Temperature dependence of ultrasonic propagation speed and attenuation in excised canine liver tissue measured using transmitted and reflected pulses. J Acoust Soc Am 115:2859-65
Gerig, Anthony L; Varghese, Tomy; Zagzebski, James A (2004) Improved parametric imaging of scatterer size estimates using angular compounding. IEEE Trans Ultrason Ferroelectr Freq Control 51:708-15
Li, Yadong; Chen, Quan; Zagzebski, James (2004) Harmonic ultrasound fields through layered liquid media. IEEE Trans Ultrason Ferroelectr Freq Control 51:146-52
Chen, Quan; Zagzebski, James A (2004) Simulation study of effects of speed of sound and attenuation on ultrasound lateral resolution. Ultrasound Med Biol 30:1297-306
Gerig, Anthony; Zagzebski, James (2004) Errors in ultrasonic scatterer size estimates due to phase and amplitude aberration. J Acoust Soc Am 115:3244-52
Gerig, Anthony; Zagzebski, James; Varghese, Tomy (2003) Statistics of ultrasonic scatterer size estimation with a reference phantom. J Acoust Soc Am 113:3430-7
Varghese, Tomy; Techavipoo, Udomchai; Liu, Wu et al. (2003) Elastographic measurement of the area and volume of thermal lesions resulting from radiofrequency ablation: pathologic correlation. AJR Am J Roentgenol 181:701-7
Tu, Haifeng; Varghese, Tomy; Madsen, Ernest L et al. (2003) Ultrasound attenuation imaging using compound acquisition and processing. Ultrason Imaging 25:245-61
Varghese, T; Zagzebski, J A; Lee Jr, F T (2002) Elastographic imaging of thermal lesions in the liver in vivo following radiofrequency ablation: preliminary results. Ultrasound Med Biol 28:1467-73
Techavipoo, U; Varghese, T; Zagzebski, J A et al. (2002) Temperature dependence of ultrasonic propagation speed and attenuation in canine tissue. Ultrason Imaging 24:246-60

Showing the most recent 10 out of 43 publications