Optimization Framework for Temporal Interference Current Tibial Nerve Stimulation in Tibial Nerves Based on In-Silico Studies

Abstract

Compared to the existing noninvasive methods, temporal interference (TI) current stimulation is an emerging noninvasive neuromodulation technique that can improve the ability to focus an electrical field on a target nerve. Induced TI field distribution depends on the anatomical structure of individual neurons, and thus the electrode and current optimization to enhance the field focus must reflect these factors. The current study presents a TI field optimization framework for focusing the stimulation energy on the target tibial nerve through extensive electrical simulations, factoring in individual anatomical differences. We conducted large-scale in-silico experiments using realistic models based on magnetic resonance images of human subjects to evaluate the effectiveness of the proposed methods for tibial nerve stimulation considering overactive bladder (OAB) treatment. The electrode position and current intensity were optimized for each subject using an automated algorithm, and the field-focusing performance was evaluated based on the maximum intensity of the electric fields induced at the target nerve compared with the electric fields in the neighboring tissues. Using the proposed optimization framework, the focusing ability increased by 12% when optimizing the electrode position. When optimizing both the electrode position and current, this capability increased by 11% relative to electrode position optimization alone. These results suggest the significance of optimizing the electrode position and current intensity for focusing TI fields at the target nerve. Our electrical simulation-based TI optimization framework can be extended to enable personalized peripheral nerve stimulation therapy to modulate peripheral nerves.

Keywords

• temporal interference stimulation
• tibial nerve stimulation
• noninvasive neurostimulation
• overactive bladder syndrome
• simulation based on MR image