Breast MRI
In the United States, breast cancer is the most common cancer in women, and is the second leading cause of cancer deaths among women (American Cancer Society). The current clinical standard to screen for breast cancer is X-ray-based mammography; however, several clinical studies have shown that MRI has much higher sensitivity for detecting cancer, especially in women who are at elevated risk for developing breast cancer. But, MRI is the more complex exam and comes at a much higher cost, which are the key reasons why it currently cannot be offered to all women.
Scientists in our group, in close collaboration with breast clinicians at Stanford Clinics, have made substantial and impactful contributions to the development of breast MRI techniques. Our ongoing research includes breast imaging at higher spatial resolution to better depict tumor features, faster data acquisition to reduce the overall time in the scanner, as well as enabling contrast-injection-free imaging.
Current breast MRI research in our group focuses on two main areas:
- Breast MRI without the injection of contrast (Diffusion-weighted MRI)
Breast cancers in MRI are shown by injecting a contrast agent, typically a Gadolinium-based substance. This method is referred to as Dynamic Contrast Enhanced (DCE) MRI. Because of the increased and "leaky" blood supply to the tumor, the tumor becomes brighter than the healthy tissue soon after injection. Advanced methods are necessary to image quickly enough to resolve the brightness changes with high image resolution.
Alternative MRI methods to assess breast cancer include T2-weighted imaging and diffusion-weighted imaging (DWI). We are exploring faster and sharper techniques to acquire these images. These methods do not require injection of a contrast agent, so may offer cheaper and wider access to MRI for many patients.
- Breast MRI with the patient laying on their back (Supine patient positioning)
During a breast MRI exam, the patient typically lays on her stomach in a position that is very uncomfortable for the patient, and it limits the sensitivity, consistency, and resolution of the imaging. Also, it limits access to a breast MRI exam for some women who are physically not able to lay in this position inside the MRI scanner. We develop methods to enable MRI with the patient laying on her back and propose that we can achieve higher image quality and improve diagnostic accuracy of detecting breast cancer even more. Supine positioning is much more comfortable for the patient, and it is also much more relevant when breast MRI images are used to guide interventional procedures (e.g. breast biopsies), which are mostly done with the patient laying on their back.
Relevant Publications
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Multishot Diffusion-Weighted MRI of the Breasts in the Supine vs. Prone Position
While breast MRI offers a more accurate detection approach than standard mammography, two challenges are (1) the uncomfortable prone position (patient lying on her stomach) and (2) the use of a contrast injection.
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Diffusion-Weighted DESS with a 3D Cones Trajectory for Non-Contrast-Enhanced Breast MRI
In this work a novel diffusion-weighted method, DW-DESS-Cones, is developed and characterized in vivo for the MRI of breast cancer without a contrast injection.
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Multi-Shot DWI of the Breast with MUSE and shot-LLR Reconstructions
This manuscript presents a clinical breast MRI study that investigates the performance of single-shot DWI and multi-shot DWI reconstructed by two different techniques (MUSE and Shot-LLR).
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A Mixed-Reality System for Breast Surgical Planning
We have developed a mixed-reality system that projects a 3D “hologram” of images from a preoperative breast MRI onto a patient using the Microsoft HoloLens.
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Fat-Based Registration of Breast Dynamic Contrast Enhanced Water Images
Dynamic contrast-enhanced breast MRI scans take 5-10 minutes to acquire, so motion between the temporal phases is a common problem that must be corrected before post-processing.
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MRI with Compressed Sensing and Variable View Sharing
A new sampling pattern enables retrospective selection of frame rates in MRI to allow for different spatiotemporal resoluiton tradeoffs and protocol optimization for different imaging applications.
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Multiband Diffusion-Weighted Breast MRI
This novel technique reduces distortion in high-resolution diffusion MRI.
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High-Resolution, 3D Diffusion-Weighted Breast MRI with DESS
High-resolution diffusion-weighted breast MRI allows for detection of small lesions and can distinguish between benign and malignant lesions.
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Rapid 3D MRI of Breast Perfusion
Breast cancer is most often detected on MRI using contrast-enhanced imaging.