Measurement of Breast Tissue Viscoelasticity Using MRI

Institution: University of California, Davis
Investigator(s): Michael Buonocore, M.D., Ph.D. -
Award Cycle: 1998 (Cycle IV) Grant #: 4IB-0127 Award: $48,396
Award Type: IDEA
Research Priorities
Detection, Prognosis and Treatment>Imaging, Biomarkers, and Molecular Pathology: improving detection and diagnosis



Initial Award Abstract (1998)
Centuries of medical experience have demonstrated that palpation, defined as applying manual pressure to the tissue to identify irregularities in tissue firmness and consistency, is a useful diagnostic tool that even today may disclose lesions that are undetected by conventional imaging. Recently, a new technique based on magnetic resonance imaging (MRI) has been reported, in which these "viscoelastic" properties of tissues, that are usually discovered by manual pressure, can be discerned by mechanically vibrating the tissue while imaging. The advantage of using MRI is that it is probably more sensitive than palpation, and does not have the limits on depth of penetration tissue that manual pressure has. The application of this new technique to breast imaging has not been reported. In this project, we propose to solve the technical challenges associated with making these measurements in the body, and to compare images with results of palpation, x-ray mammography, and standard MRI, to ascertain the value of the technique in identifying abnormal tissue.

This project proposes the development and testing of a new technological strategy and innovative approach to the early detection of primary breast cancer. The major feature of the approach is the use of a custom-made device to generate mechanical waves in the tissues, coupled with advanced MRI sequences that will measure the small physical displacements of the tissue caused by the mechanical waves at each point within the breast. The technique extends the role of palpation in breast examination, by providing objective and quantitative measurements of these tissue properties. Developing this new approach may significantly improve the ability to detect breast lesions, and may also provide data that is needed to better understand, and improve the accuracy of, the findings of manual palpation. Success of the project could lead to a fundamental change in the way breast cancer patients are diagnosed, in that it would provide strong incentive to obtain MRI examinations early in the diagnostic workup (even screening) of patients. The technique significantly adds to the growing armamentarium of MRI methods that are applicable to the early detection and diagnosis of breast cancer.

The project involves the close collaboration of an imaging scientist in Radiology and a clinician in Surgical Oncology. Such collaborations are necessary for new MRI technical advances to have impact in the clinical setting. If the new MRI technique proves to be successful, the proposed MRI protocol would be suitable as a standard breast diagnostic exam. This is because the protocol provides: 1) detailed images of the breast anatomy, 2) special contrast enhanced images for improved discrimination of benign versus malignant lesions, and 3) images of tissue elasticity and viscosity, with high sensitivity to abnormal tissue based on abnormal mechanical properties. The successful outcome of the project could result in a rapid transition of the technique into practical application, through mainstream health care providers.

This project could benefit the breast cancer constituency of California by providing a new noninvasive method for early detection of breast disease that could be implemented and used at the vast majority of MRI sites throughout the state.


Final Report (2001)
Centuries of medical experience have demonstrated that palpation, defined as applying manual pressure to the tissue to identify irregularities in tissue firmness and consistency, is a useful diagnostic tool that may disclose lesions that are undetected by imaging. Recently, a new technique based on magnetic resonance imaging (MRI) has been reported, in which these "viscoelastic" properties of tissues, that are usually discovered by manual pressure, can be discerned.

This project has developed and tested a new technological strategy and innovative approach to the early detection of primary breast cancer. The major feature of the approach is the development of a custom made device to generate mechanical waves in breast tissue, and the development of advanced MRI techniques to measure the small physical displacements of the tissue caused by the mechanical waves.

We developed the acoustic wave device, MRI pulse sequences, gel phantoms and image reconstruction software necessary for creating and detecting the mechanical waves propagating through tissue. We have built a breast MRI coil that can be used to perform standard breast imaging as well as viscoelasticity measurements in the breast. The method has been fully tested and we have confirmed that the images are consistent and repeatable. Future work includes testing in human subjects, and development of methods for calculating the tissue viscoelasticity from the images.

This new approach may significantly improve the ability to detect breast lesions early, and may also provide data that is needed to improve the accuracy of manual palpation. It may ultimately lead to a fundamental change in the way breast cancer patients are diagnosed. The approach provides another incentive to obtain MRI examinations early in the screening and diagnostic workup of patients.