Portable and Radiation-Free Imaging with Magnetic Nanoparticles

Researchers at the University of Würzburg in Germany have developed a portable scanner that is the first to be able to image humans using Magnetic Particle Imaging (MPI). The technology could provide a radiation-free alternative to techniques such as X-ray fluoroscopy and digital subtraction angiography for minimally invasive endovascular procedures, and is well suited for viewing processes such as blood flow. Previous inceptions of MPI technology were too large and expensive and were primarily designed for use in experimental animals. This is the first version of the technology that is small enough for portability and it has been designed for human patients. The procedure involves administering magnetic nanoparticles to the patient, and then the scanner measures changes in their response to a magnetic field over time to visualize internal processes in the body.

Medical imaging has transformed how clinicians can investigate the internal working of our bodies, and is a mainstay of medical diagnostics. However, that doesn’t mean that it can’t be improved and updated. A major limitation of many imaging modalities is their use of ionizing radiation, which can cause health risks for patients and healthcare staff alike. Developing radiation-free imaging systems is a noble goal.

“As with positron emission tomography, which relies on the administration of radioactive substances as markers, this method has the great advantage of being sensitive and fast without ‘seeing’ interfering background signals from tissue or bone,” said Volker Behr, a researcher involved in the study.

This latest imaging modality is not new, having been trialed in experimental animals previously, but this is the first time that researchers have created an MPI imager that is specifically for human patients, and which is small and light enough to be relatively easily portable. The system involves using magnetic nanoparticles as a tracer within the body that can affect magnetic fields, providing a measurable signal that reveals dynamic processes within the body, such as blood flow.

“In this process, the magnetisation of nanoparticles is specifically manipulated with the help of external magnetic fields, whereby not only their presence but also their spatial position in the human body can be detected,” said Patrick Vogel, another researcher involved in the study.   

Study in journal Scientific Reports: iMPI: portable human-sized magnetic particle imaging scanner for real-time endovascular interventions

Via: University of Würzburg