A new MRI imaging modality from Philips has shown itself to be effective in viewing cardiac blood flow and the movement of the heart in a pre-clinical study. The technology, called Magnetic Particle Imaging, may one day become standard practice in visualizing functional characteristics of the coronary and general circulatory systems, or can even help physicians one day to view regional blood perfusion in real time.
Philips’ Magnetic Particle Imaging uses the magnetic properties of injected iron-oxide nanoparticles to measure the nanoparticle concentration in the blood. Because the human body contains no naturally occurring magnetic materials visible to MPI, there is no background signal. After injection, the nanoparticles therefore appear as bright signals in the images, from which nanoparticle concentrations can be calculated. By combining high spatial resolution with short image acquisition times (as short as 1/50th of a second), Magnetic Particle Imaging can capture dynamic concentration changes as the nanoparticles are swept along by the blood stream. This could ultimately allow MPI scanners to perform a wide range of functional cardiovascular measurements in a single scan. These could include measurements of coronary blood supply, myocardial perfusion, and the heart’s ejection fraction, wall motion and flow speeds.
The results obtained from Philips’ experimental MPI scanner mark an important step towards the development of a whole-body system for use on humans. Some of the technical challenges in scaling up the system relate to the magnetic field generation required for human applications. Others lie in the measurement and processing of the extremely weak signal emitted by the nanoparticles.
Press release: Philips announces breakthrough in new medical imaging technology
Abstract in Physics in Medicine and Biology…