Neural Implant Insertion System using Ultrasonic Vibration to Reduce Tissue Dimpling and Improve Insertion Precision of Floating Arrays in the Neocortex

点击翻译按钮获取中文摘要

This Phase I SBIR develops and tests a system for vibrating neural implant floating arrays during insertion to reduce insertion force, dimpling, tissue damage, and bleeding. The approach will allow precise insertion of electrode shanks into shallow cortical layers. This proposal is in response to PAR-15-091 BRAIN Initiative: Development, Optimization, and Validation of Novel Tools and Technologies for Neuroscience Research. Problem to be solved: Penetrating electrode arrays provide direct access to neural signals across the central and peripheral nervous system with high spatial resolution. Sophisticated floating array implants may revolutionize treatment for a range of medical conditions, including prosthetic motor control and proprioception for amputees, and brain-machine interfacing for paraplegics. Unfortunately, implantation of floating arrays, which are commonly comprised of numerous high-density electrode shanks, applies forces to neural tissue resulting in substantial compression (dimpling). This dimpling often prohibits uniform shank insertion, increases trauma and bleeding at the implant site and may accentuate glial scaring, neural cell death, and device failure. Current insertion procedures for high-density floating arrays employ high-speed and/or pneumatic insertion systems or manual insertion, which can cause significant bleeding and tissue damage. This project develops an Ultrasonic Precision Insertion system for Floating Arrays (UPIND-FA) to reduce insertion force, tissue dimpling and damage, ultimately enhancing electrode placement accuracy and functionality. Hypothesis: Ultrasonic vibration of high-density neural electrode floating arrays (FAs) will reduce dimpling to facilitate complete insertion of all electrode shanks without requiring advancement beyond target depth (overshoot), reduce Foreign Body Response (FBR) due to insertion trauma and improve electrode performance, as compared to non-vibrated and/or high-speed insertion (i.e., Commercial pneumatic inserter). Aim 1: Development of UPIND-FA for insertion of FAs, with minimized dimpling and insertion force, and easy release. Acceptance Criteria. >70% reduction in tissue dimpling and insertion force compared to non-vibrated insertion; improved insertion accuracy (±100 μm of target depth) of all electrode shanks at shallow depths (<1000 μm) over a commercial insertion; <50 μm perturbation of FA body during release post-insertion. Aim 2: Show that UPIND-FA successfully inserts floating arrays in vivo without electrode damage. Acceptance Criteria: >70% reduction in dimpling compared to control insertion; complete insertion of all electrode shanks without target depth overshoot; significant improvement in array performance and reduction in brain FBR (p<0.05). Aim 3: Confirm UPIND-FA array insertion in vivo in a gyrencephalic neocortex significantly reduces tissue damage and brain FBR over non-vibrated and the commercial insertions. Acceptance Criteria: >70% dimpling reduction over control insertion; complete insertion of all electrode shanks without target depth overshoot, and significant (p<0.05) reduction in brain FBR compared to the commercial pneumatic inserter.