Original Research ARTICLE
The µDBS: Multiresolution, directional Deep Brain Stimulation for improved targeting of small diameter fibers
- 1Department of Biomedical Engineering, College of Engineering, University of Utah, United States
- 2Department of Neurosurgery, School of Medicine, University of Utah, United States
- 3Department of Electrical and Computer Engineering, University of Utah, United States
- 4Department of Neurology, School of Medicine, University of Utah, United States
- 5Department of Psychiatry, School of Medicine, University of Utah, United States
- 6Nanofab Institute, University of Utah, United States
Directional deep brain stimulation (DBS) leads have recently been approved and used in patients, and growing evidence suggests that directional contacts can increase the therapeutic window by redirecting stimulation to the target region while avoiding side-effect-inducing regions. We outline the design, fabrication, and testing of a novel directional DBS lead, the µDBS, which utilizes microscale contacts to increase the spatial resolution of stimulation steering and improve the selectivity in targeting small diameter fibers. We outline the steps of fabrication of the µDBS, from an integrated circuit design to postprocessing and validation testing. We tested the onboard digital circuitry for programming fidelity, characterized impedance for a variety of electrode sizes, and demonstrated functionality in a saline bath. In a computational experiment, we determined that reduced electrode sizes focus the stimulation effect on small, nearby fibers. Smaller electrode sizes allow for a relative decrease in small-diameter axon thresholds compared to thresholds of large-diameter fibers, demonstrating a focusing of the stimulation effect within small, and possibly therapeutic, fibers. This principle of selectivity could be useful in further widening the window of therapy. The µDBS offers a unique, multiresolution design in which any combination of microscale contacts can be used together to function as electrodes of various shapes and sizes. Multiscale electrodes could be useful in selective neural targeting for established neurological targets and in exploring novel treatment targets for new neurological indications.
Keywords: Deep Brain Stimulation 1, Directional Electrodes 2, Electrode Fabrication 3, Computational Modeling 4, Neural Targeting 5
Received: 23 Aug 2019;
Accepted: 11 Oct 2019.
Copyright: © 2019 Anderson, Anderson, Lanka, Sharma, Butson, Baker and Dorval. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Alan Dorval, Department of Biomedical Engineering, College of Engineering, University of Utah, Salt Lake City, 84112-9458, Utah, United States, email@example.com