Background: Liver fibrosis/cirrhosis afflicts hundreds of millions of patients worldwide and 900,000 Americans. Liver biopsy, currently the gold standard for the diagnosis of liver fibrosis, is invasive and may occasionally cause significant complications, which limits the screening of at-risk populations, treatment monitoring, and follow-up. Current serum markers and classic medical imaging such as ultrasound, CT, or MRI do not have sufficient sensitivity/specificity for fibrosis evaluation. Recent studies show that tissue elasticity (i.e. stiffness) may be used for liver fibrosis staging. Herein we propose a novel ultrasound method, Shearwave Ultrasound Dispersion Vibrometry (SDUV), for noninvasive, biopsy-like quantification of elasticity as well as viscosity for liver fibrosis staging. Method: SDUV uses an ultrasound "push" beam within FDA safety limits to stimulate formation of propagating harmonic shear waves in the studied tissue. The propagation speed of induced shear waves is frequency dependent (dispersive) and relates to the tissue's mechanical properties. Shear wave speeds at multiple frequencies (typically hundreds of Hertz) are measured by a separate ultrasound "detect" beam in pulse echo mode and fit with a theoretical dispersion model to inversely solve for tissue elasticity and viscosity. Preliminary studies in tissue-mimicking phantom and striated muscle are very promising. A special pulse sequence has been developed to facilitate a single ultrasound array transducer for both push and detect function, which makes SDUV compatible with current ultrasound scanners. Feasibility of this pulse sequence has been validated with in vivo measurements in normal porcine liver using in-house instrumentation.
Aims : 1. Implement SDUV on a commercial ultrasound scanner. 2. Calibrate and optimize the prototype with phantom, in vitro tissue, and in vivo animal experiments. 3. Conduct a clinical research on patients with suspected hepatic fibrosis who are scheduled to have a clinically indicated liver biopsy. Successful completion of this project should result in a new clinical technique, SDUV, for noninvasive, fast, economical, and reliable "virtual biopsy" for fibrosis staging.

Public Health Relevance

Successful completion of this project should result in a new ultrasound technique for safe, fast, economical, and reliable staging of liver fibrosis/cirrhosis, which afflicts hundreds of millions of patients worldwide and 900,000 Americans. This technique can be used as a noninvasive alternative to liver biopsy for the screening of at-risk populations, treatment monitoring, and follow-up of patients with chronic liver diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK082408-04
Application #
8288196
Study Section
Medical Imaging Study Section (MEDI)
Program Officer
Doo, Edward
Project Start
2009-07-01
Project End
2014-06-30
Budget Start
2012-07-01
Budget End
2013-06-30
Support Year
4
Fiscal Year
2012
Total Cost
$317,746
Indirect Cost
$104,574
Name
Mayo Clinic, Rochester
Department
Type
DUNS #
006471700
City
Rochester
State
MN
Country
United States
Zip Code
55905
Mehrmohammadi, Mohammad; Song, Pengfei; Meixner, Duane D et al. (2015) Comb-push ultrasound shear elastography (CUSE) for evaluation of thyroid nodules: preliminary in vivo results. IEEE Trans Med Imaging 34:97-106
Dillman, Jonathan R; Chen, Shigao; Davenport, Matthew S et al. (2015) Superficial ultrasound shear wave speed measurements in soft and hard elasticity phantoms: repeatability and reproducibility using two ultrasound systems. Pediatr Radiol 45:376-85
Nabavizadeh, Alireza; Greenleaf, James F; Fatemi, Mostafa et al. (2014) Optimized shear wave generation using hybrid beamforming methods. Ultrasound Med Biol 40:188-99
Zhao, Heng; Song, Pengfei; Meixner, Duane D et al. (2014) External vibration multi-directional ultrasound shearwave elastography (EVMUSE): application in liver fibrosis staging. IEEE Trans Med Imaging 33:2140-8
Zhao, Heng; Chen, Jun; Meixner, Duane D et al. (2014) Noninvasive assessment of liver fibrosis using ultrasound-based shear wave measurement and comparison to magnetic resonance elastography. J Ultrasound Med 33:1597-604
Song, Pengfei; Manduca, Armando; Zhao, Heng et al. (2014) Fast shear compounding using robust 2-D shear wave speed calculation and multi-directional filtering. Ultrasound Med Biol 40:1343-55
Sarvazyan, Armen P; Urban, Matthew W; Greenleaf, James F (2013) Acoustic waves in medical imaging and diagnostics. Ultrasound Med Biol 39:1133-46
Chen, Shigao; Sanchez, William; Callstrom, Matthew R et al. (2013) Assessment of liver viscoelasticity by using shear waves induced by ultrasound radiation force. Radiology 266:964-70
Song, Pengfei; Urban, Matthew W; Manduca, Armando et al. (2013) Comb-push ultrasound shear elastography (CUSE) with various ultrasound push beams. IEEE Trans Med Imaging 32:1435-47
Song, Pengfei; Zhao, Heng; Urban, Matthew et al. (2013) Improved Shear Wave Motion Detection Using Pulse-Inversion Harmonic Imaging with a Phased Array Transducer. IEEE Trans Med Imaging :

Showing the most recent 10 out of 14 publications