A comprehensive computational and experimental study of deep brain stimulation*

Deep brain stimulation (DBS) is an established treatment for Parkinson's disease, in which a radiofrequency (RF) probe is inserted and then removed from the brain prior to electrode localization. To improve the accuracy of clinical operations, it is critical to establish a better understanding of the dynamics of probe-tissue interactions. In this paper, we present a comprehensive computational and experimental study to simulate probe insertion and removel process. A dynamic explicit, Coupled-Eulerian-Lagrangian (CEL) based, linear finite element (FE) 3D model was constructed, which consisted of an RF probe and a 1.5% w/w agar gel block. For an insertion velocity consistent with the clinical application, the contact force and temporal-spacial opening and closing of the channel created by the RF proble, was predicted. Correspondingly, an experimental setup was developed. An RF probe, instumented with a load cell, was inserted into, and then revmoved from an agar gel block, at the same velocity as the FE model. The reaction force was measured which agrees with with the numerical simulation. A high-speed camera was used to capture the channel opening and closing, which also agrees with the FE simulation results, validating the numberal approach. The paper improves our understanding of the fluid-structure interaction between the RF probe and the the soft gel. It lays the foundation for a more comprehensive study of deep brain stimulation that involves real tissue properties.