In the world of medical imaging, no single technology provides all the answers for the critical procedure of breast cancer biopsy.
Magnetic resonance imaging (MRI), for example, produces clear, highly revealing images of potential breast cancer lesions, but lacks practicality in obtaining a biopsy sample. Ultrasound imaging, on the other hand, is less revealing than MRI but provides the real-time images physicians need to visualize their target.
A team of engineers and medical researchers at UW-Madison is working with a Madison biomedical firm, Marvel Medtech LLC, to merge the best of these technology worlds.
The team is developing a new real-time visualization approach to using MRI in the breast biopsy process, an advance that could lead to far more precise biopsies, shorter procedure times and reduced anxiety for patients. “Ultrasound is the technology of choice right now for image-guided biopsies, primarily because it’s easy to use and offers the real-time imaging,” says Associate Professor Walter Block (left). “Clearly, radiologists need to have confidence when conducting a biopsy that they are in the lesion. But many of the lesions detected by MRI are not visible in ultrasound.”
Lesions not detected by ultrasound have a malignancy rate of above 20 percent. For that reason, the American Cancer Society recommends using MRI as the top surveillance tool for high-risk breast cancer patients, which includes an estimated 1.4 million American women. The “blind” approach to MRI-assisted biopsies means that even the slightest movement of the patient or the tissue can shift the target and lead to a failed biopsy, causing additional painful readjustments or return visits.
The new technology tackles two challenges. First, current MRI scanner design makes it nearly impossible for interventional access to the patient during imaging. Block’s research team developed a different kind of MR breast coil that leaves open a variety of angles accessible to a biopsy needle. The second challenge is in designing a functional device within MRI’s high magnetic field environment. For this, the team is partnering with Mechanical Engineering Assistant Professor Michael Zinn, who is building a robotic arm that would control the needle with piezoelectric motors.
Other collaborators include (from left, next to Block) Radiology Assistant Professor Roberta Strigel, Medical Physics Researcher Ethan Brodsky, Radiology Associate Professor Frederick Kelcz, and Marvel Medtech CEO Ray Harter.