Development of Magnetic Particle Imaging
Creators: name: University Of California Office Of The President
Publisher: name: University of California Office of the President
publisherIdentifier: https://ror.org/00dmfq477
publisherIdentifierScheme: ROR
Year: 2024

description: MRI, CT, Ultrasound, and X-ray are all important medical imaging methods that help physicians diagnose diseases. However, these methods are not always ideal. For example, about 90% of positive X-ray mammograms turn out to be benign after biopsy, causing needless worry and surgery. As another example, the current standard test for diagnosing coronary artery disease is X-ray catheterized angiography. But this exam has serious risks—1 out of 1000 patients will die during the diagnostic procedure. This Berkeley-GE research collaboration is aimed to solve these two compelling medical challenges with a completely new imaging modality, called Magnetic Particle Imaging (MPI). In MPI, we image a magnetic contrast agent after it is injected into the body. Unlike X-ray and CT, this method has no ionizing radiation, so it is perfectly safe for humans. The magnetic contrast agents are already FDA-approved for other applications, so those, too, are safe. The biggest advantage is that the Magnetic Particle Imaging method will be able to see small blood vessels without being obscured by the blood, muscle and bone that always obscure current medical imaging methods. Unfortunately, the current MPI method is too blurry (about 5-mm pixels), so the main goal of our research is to reduce this blur dramatically. We plan to make MPI images as good as MRI (1-mm pixels) or even, if all goes as planned, as good as CT (about 1/3-mm pixels). My research group at UC Berkeley Bioengineering has constructed the first mouse MPI scanner and also the first MPI spectrometer in North America. We also found out theoretically that the current contrast agents are not at all ideal for MPI. Indeed, we believe we can simply substitute much larger nanoparticles (30 nm, about 2.5 times bigger than the commercial contrast agents) then we can fix the blur problem. In theory, the bigger particles should also create a better quality image, with less visible noise. We are very fortunate that four nanoparticle experts worldwide are willing to share their expertise and allow us to test their larger contrast agent particles. We will improve our hardware, software, and then test the bigger nanoparticles to verify the predicted reductions in blur. We also have several new ideas to speed up the exam. Finally we will carefully measure the MPI image quality and compare it to existing medical imaging methods. Here we plan to consult with cardiologists at Stanford University and oncologists at UCSF. We are collaborating on this Research Proposal with GE Healthcare, one of the world’s leading medical imaging equipment manufacturers. They have a large group of scientists and engineers live and work in the San Francisco Bay Area who have collaborated with UC Berkeley and UCSF researchers for decades. The GE researchers share our hope that this new imaging modality will one day obviate the problems mentioned above with X-ray mammography and X-ray catheterized angiography.