This work investigates optimal magnetic nanoparticle (MNP) injection strategies in three-dimensional (3D) tumor models to enhance the magnetic hyperthermia efficacy. We consider three tumor models with increasing geometric complexities: a spherical tumor, a simple irregular tumor (two connected spheres of different sizes), and a complex irregular tumor (three connected spheres of varying sizes). Centrosymmetric MNP distributions are employed for the spherical model, whereas asymmetric distributions are applied for the irregular models. The rapid convergence of the optimization demonstrates the efficiency and effectiveness of this 3D optimization framework. For the spherical tumor model, multi-site injections significantly enhance therapeutic outcomes under a 20-min waiting limit, whereas a single-site injection with a 114.9-min waiting time achieves 100% tumor ablation without damaging adjacent healthy tissue. Two injection sites suffice for the simple irregular tumor model, while a three-site strategy is optimal for the complex irregular model, indicating a relationship between required injection number and tumor geometry. Furthermore, the optimal MNP injection strategies correlate positively with the locations and sizes of the connected spheres. These findings produce more practical optimal strategies and provide broader, clinically relevant guidance for magnetic hyperthermia treatment. • Optimal magnetic nanoparticle injection strategies in three dimensions are explored. • Various irregularities in tumor models represent some of the most practical shapes. • Required injection number correlates with the number of connected spheres. • Optimal injection strategies correlate positively with sizes and locations of the spheres. • The findings yield more practical strategies and clinically relevant guidance.
Jiang et al. (Thu,) studied this question.