Image-Guided Thermal Therapy Using Magnetic Particle Imaging and Magnetic Fluid Hyperthermia

Abstract Magnetic nanoparticles (MNPs) find applications in magnetic fluid hyperthermia (MFH), where the heat dissipated from the MNPs in the presence of an alternating magnetic field is used to treat cancer. However, upon systemic delivery MNPs are also readily phagocytosed by liver and spleen macrophages, leading to accumulation in these organs and thus resulting in nonspecific heating and damage to these healthy organs during MFH. A potential solution to this problem is using magnetic field gradients such as those used in magnetic particle imaging (MPI), a tracer imaging technology which makes the use of MNP's nonlinear magnetization response to a scanned field gradient to obtain the MNP distribution. The field gradient of MPI can be used to localize the region where MNPs dissipate heat, whereas its imaging capability can be utilized for real-time thermal therapy. In this chapter, we introduce and discuss this emerging field of image-guided thermal therapy using MPI and MFH.