Comprehensive Evaluation of Magnetic Particle Imaging (MPI) Scanners for Biomedical Applications

Magnetic particle imaging (MPI) is an emerging tomographic imaging technique that tracks and quantitatively measures the spatial distribution of the superparamagnetic iron oxide nanoparticles (SPIONs). It is a radiation-free, background-free, and signal attenuation-free imaging modality that utilizes the non-linear behavior of the tracer agents. The minimum acquisition time, high spatial resolution, and extreme sensitivity make it ideal for medical imaging in comparison to magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography (PET). SPIONs are the main source of signal generation and have a significant influence on MPI scanner characteristics. Many research groups in the world are working to produce optimal tracer agents with a low toxicity profile for MPI applications. Versatile MPI scanners are developed and implemented at the pre-clinical stage to evaluate the performance of the system parameters. This review aims at giving an overview of the current developments and significant achievements of the tracer agents, imager design, image reconstruction, and potential applications of MPI scanners since their first exposure to the scientific world in 2005.