Safety Measurements for Heating of Instruments for Cardiovascular Interventions in Magnetic Particle Imaging (MPI) ‐ First Experiences

Abstract

Magnetic particle imaging (MPI) has emerged as a new imaging method with the potential of delivering images of high spatial and temporal resolutions and free of ionizing radiation. Recent studies demonstrated the feasibility of differentiation between signal-generating and non-signal-generating devices in Magnetic Particle Spectroscopy (MPS) and visualization of commercially available catheters and guide-wires in MPI itself. Thus, MPI seems to be a promising imaging tool for cardiovascular interventions. Several commercially available catheters and guide-wires were tested in this study regarding heating. Heating behavior was correlated to the spectra generated by the devices and measured by the MPI. The results indicate that each instrument should be tested separately due to the wide spectrum of measured temperature changes of signal-generating instruments, which is up to 85°C in contrast to non-signal-generating devices. Development of higher temperatures seems to be a limitation for the use of these devices in cardiovascular interventions.

Magnetic Particle Imaging (MPI): Experimental Quantification of Vascular Stenosis Using Stationary Stenosis Phantoms

“…First results towards real time MPI were already presented recently by Salamon et al [55]. For MPI-guided interventions the safety of devices like guide wires and stents also has to be considered [56]. …”

Magnetic Particle / Magnetic Resonance Imaging: In-Vitro MPI-Guided Real Time Catheter Tracking and 4D Angioplasty Using a Road Map and Blood Pool Tracer Approach

“…They presented the feasibility of MPI of SPIOs labeled endovascular instruments at high temporal resolution [ 6 ] and introduced the first magnetic coating of interventional devices for MPI visualization with a coating thickness of about 500 μm [ 13 ]. Various interventional instruments have been investigated concerning potential heating in MPI [ 7 ]. For our study we used instruments that showed neither heating nor artifacts in MPI.…”

“…Potential MPI utilizations include cardiovascular applications (angiographies, cardiac vitality evaluation, tissue perfusion, plaque labeling, endovascular interventions, detection of bleeding sources) or applications in tumour, molecular, and cellular imaging (passive and active targeting, molecular therapies, cellular labeling and cell monitoring) [ 5 ]. For the broad sector of potential interventional applications, as therapeutic endovascular or thermoablative approaches, Haegele et al demonstrated promising results in initial experimental studies [ 6 ], although potential heating of the material has to be considered [ 7 ] and labelling of endovascular devices has to be optimized. For in-vivo MPI of interventional instruments currently two strategies are pursued.…”

Magnetic particle imaging for radiation-free, sensitive and high-contrast vascular imaging and cell tracking

“…We note that the theranostic potential of MPI extends far beyond guiding cell-based treatments. Although this review focuses on MPI imaging applications, extensive work has also been performed demonstrating the utility of MPI for ionizing radiation-free surgical guidance 34–37 and therapeutic guidance, such as with magnetic hyperthermia 38–42 .…”