Electric field distributions in realistic 3D rat head models during alternating electric field (AEF) therapy: a computational study

Abstract

Objective. Application of alternating electrical fields (AEFs) in the kHz range is an established treatment modality for primary and recurrent glioblastoma. Preclinical studies would enable innovations in treatment monitoring and efficacy, which could then be translated to benefit patients. We present a practical translational process converting image-based data into 3D rat head models for AEF simulations and study its sensitivity to parameter choices. Approach. Five rat head models composed of up to 7 different tissue types were created, and relative permittivity and conductivity of individual tissues obtained from the literature were assigned. Finite element analysis was used to model the AEF strength and distribution in the models with different combinations of head tissues, a virtual tumor, and an electrode pair. Main results. The simulations allowed for a sensitivity analysis of the AEF distribution with respect to different tissue combinations and tissue parameter values. Significance. For a single pair of 5 mm diameter electrodes, an average AEF strength inside the tumor exceeded 1.5 V cm−1, expected to be sufficient for a relevant therapeutic outcome. This study illustrates a robust and flexible approach for simulating AEF in different tissue types, suitable for preclinical studies in rodents and translatable to clinical use.