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bioRxiv · 10.1101/786459

Group-Level Analysis of Induced Electric Field in Deep Brain Regions by Different TMS Coils

Gomez-Tames, J.·Hamasaka, A.·Hirata, A.·Laakso, I.·Lu, M.·Ueno, S.
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Abstract

Deep transcranial magnetic stimulation (dTMS) is a non-invasive technique used in treating depression. In this study, we computationally evaluate group-level dosage during dTMS with the aim of characterizing targeted deep brain regions to overcome the limitation of using individualized head models to characterize coil performance in a population.\n\nWe use an inter-subject registration method adapted to deep brain regions that enable projection of computed electric fields (EFs) from individual realistic head models (n = 18) to the average space of deep brain regions. The computational results showed consistent group-level hotspots of the EF in deep brain region with intensities between 20%-50% of the maximum EF in the cortex. Large co-activation in other brain regions was confirmed while half-value penetration depth from the cortical surface was smaller than 2 cm. The halo figure-8 assembly and halo circular assembly coils induced the highest EFs for caudate, putamen, and hippocampus.\n\nGeneralized induced EF maps of deep regions show target regions despite inter-individual difference. This is the first study that visualizes generalized target regions during dTMS and provides a method for making informed decisions during dTMS interventions in clinical practice.

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Gomez-Tames, J., Hamasaka, A., Hirata, A., Laakso, I., Lu, M., Ueno, S.. 2019-09-29. Group-Level Analysis of Induced Electric Field in Deep Brain Regions by Different TMS Coils. https://doi.org/10.1101/786459

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