Theranostics based on MPI for brain interventions: an in vivo pilot study

Magnetic particle imaging (MPI)-based magnetic fluid hyperthermia (MFH) enables localized and non-invasive application in conjunction with image guided therapeutic control which represents a significant advantage to established methods of curative heat delivery. Although phantom experiments have shown promising results with adequate MFH performance, transition into clinical and pre-clinical practice, faces several challenges. First and foremost, non-invasive, i.e., systemic administration of nanoparticle tracers, results in steadily moving MFH targets that transport the generated heat away from the targetted region. In this pilot study we investigate localized MFH efficiency in the rat brain, during systemic administration of commercial superparamagnetic iron oxide nanoparticles (SPION). For that we used an experimental set up consisting of a custom heating insert integrated into a commercial MPI-scanner. We observed a slight local temperature increase (∼0.3-0.5 K) in the brain following simoultanous SPION administration and localized MFH application.