Electrical Impedance Tomography Based Closed-loop Tumor Treating Fields in Dynamic Lung Tumors

TL;DR

This paper introduces a novel closed-loop TTFields system for lung tumors that uses electrical impedance tomography to adapt to respiratory motion, maintaining effective electric field levels during different breathing phases.

Contribution

It presents a new closed-loop approach integrating EIT for real-time respiratory monitoring to optimize TTFields therapy in dynamic lung tumors.

Findings

Closed-loop TTFields maintains higher electric field strength across respiratory phases.

Electrical conductivity variations affect electric field distribution during respiration.

Proposed method improves consistency of electric field delivery in lung tumor treatment.

Abstract

Tumor Treating Fields (TTFields) is a non-invasive anticancer modality that utilizes alternating electric fields to disrupt cancer cell division and growth. While generally well-tolerated with minimal side effects, traditional TTFields therapy for lung tumors faces challenges due to the influence of respiratory motion. We design a novel closed-loop TTFields strategy for lung tumors by incorporating electrical impedance tomography (EIT) for real-time respiratory phase monitoring and dynamic parameter adjustments. Furthermore, we conduct theoretical analysis to evaluate the performance of the proposed method using the lung motion model. Compared to conventional TTFields settings, we observed that variations in the electrical conductivity of lung during different respiratory phases led to a decrease in the average electric field intensity within lung tumors, transitioning from end-expiratory (1.08 V/cm) to end-inspiratory (0.87 V/cm) phases. Utilizing our proposed closed-Loop TTFields approach at the same dose setting (2400 mA, consistent with the traditional TTFields setting), we can achieve a higher and consistent average electric field strength at the tumor site (1.30 V/cm) across different respiratory stages. Our proposed closed-loop TTFields method has the potential to improved lung tumor therapy by mitigating the impact of respiratory motion.