Magnetic Resonance Imaging in Breast Cancer
Magnetic Resonance Imaging (MRI) offers a number of advantages over other imaging methods for detecting breast cancer. It is non-invasive and can provide exquisite high-resolution, three dimensional images which detect cancers based on tumour angiogenesis. In this context, we are optimizing MRI for a number of clinical and research applications for breast cancer patients. One important area focuses on the development of optimized MRI imaging methods specific to the breast. This involves novel MRI pulses sequences and processing methods in conjunction with appropriate RF systems for efficient bilateral imaging. We have developed extensive technology to use MRI to guided biopsy and other interventional procedures. We are developing means to fuse imagery from MRI together with ultrasound (US) data to give further insight in tissue biology for diagnosis and aid in minimally invasive interventions. A further extension of MR exploits its exquisite motion sensitivity to gain a better understanding of ultrasound biophysics as it relates to thermal therapy.We were the first to demonstrate that MRI could be used to generate three dimensional images of propagating ultrasound fields in tissue by detecting the nanometer scale motions associated with the ultrasound energy. Finally, we are mounting a new research direction aimed at imageguided therapy.
Currently, surgeons remove tumours often without a clear knowledge of the true location and extent of the tumour mass. We are developing approaches to integrate 3D MRI into this process. This capability draws on concepts related to augmented reality, image fusion and dynamic imaging or tracking of relevant tissue structures. To this end we are developing an experimental operating theatre for human applications to test these concepts.
Together with researchers from Oncology and Radiology we have been running an extensive study to assess the efficacy of MRI for screening women at risk for hereditary breast cancer. The methods used in this study were developed entirely in our laboratory. Early results indicate that MRI has approximately twice the sensitivity compared to mammography or ultrasound in this population. This exciting study is now one of the largest in the world on the application of MRI for breast surveillance.
Taken as a whole, our research is devoted to the challenge of developing new MRI methods for detection, diagnosis, staging and therapy of breast cancer. Our research applies concepts in engineering and basic physics that can be applied in a clinically relevant manner. For further details see Plewes Group Web Page: http://www.sunnybrook.utoronto.ca/dbp/mainfr.html
Graduate Students:
- Rachel Chan
Selected References:
Link to Pubmed Publications-
Sack I, MacGowan CK,Samani A, Luginbuhl C, Oakden W, Plewes DB, Observation of non-linear shear wave propagation using Magnetic Resonance Elastography, Magn Reson Med. Oct;52(4):842-850, 2004
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Desmond K, Ramsay E, Plewes DB, Comparison of Biphasic and Intermittent Fat-Saturation for Breast MRI. Journal of Magnetic Resonance Imaging, 25(6), 1293-1298, 2007
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Samani A, Plewes DB, An inverse problem solution for measuring the elastic modulus of in tact breast tissue tumours. Physics in Medicine and Biology. January, 52, 1247-1260, 2007 (this paper was selected as a featured article)
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Hoory T, Ramsay E, Plewes DB, Effect of Gd-DTPA induce susceptibility on single-point Dixon fat/water separation. Magn Reson Med. 925-929, 59(4), 2008
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Chan R, Ramsay ER , Cunningham C., Plewes DB, Temporal Stability of 3D-PR Adaptive MRI Using Multidimensional Golden Means, Magnetic Resonance in Medicine. 61:354-363, 2009
