Microelectrode Array Insertion System using Ultrasonic Vibration to Improve Insertion Mechanics, Reduce Tissue Dimpling and Trauma, and Improve Placement Precision in the Neocortex - This Phase II SBIR further develops and tests a system that employs ultrasonic vibration to improve the
insertion mechanics for multichannel penetrating electrode arrays. This proposal is in response to PA-18-871
BRAIN Initiative: Development, Optimization, and Validation of Novel Tools and Technologies for
Neuroscience Research – including ‘Iterative refinement of such tools and technologies with the end-user
community’. The long-term goal of Actuated Medical, Inc. is to develop technology enabling accurate
placement of penetrating neural electrode arrays at target locations with minimal tissue trauma and
displacement, ultimately paving the way for clinical use of neural implants.
Penetrating neural implants provide direct access to extracellular neural signals across the central and
peripheral nervous systems with both high temporal and spatial resolution. Unfortunately, the implantation of
neural electrode arrays, commonly comprised of numerous closely spaced shanks, applies forces to neural
tissue resulting in significant compression (dimpling), prohibiting uniform shank insertion, and increasing the
risk of trauma, bleeding and inflammation at the implant site. These issues can increase the chronic foreign
body response (FBR) leading to neural cell death, glial scaring, and device failure. Phase I demonstrated the
ability to releasably grip and deliver ultrasonic vibration to a range of commercially available implant types,
including floating-style arrays, resulting in reductions of insertion force and surface dimpling in bench studies of
up to 80-90% for most implants tested. In vivo, ultrasonic vibration significantly reduced brain surface dimpling
(~50%, p<0.01) and exhibited evidence of reduced bleeding, while preserving device function as evidenced by
post implant neural recordings. Furthermore, preliminary work suggests significant potential for the ultrasonic
vibration to improve insertion of ultrafine (8-15 µm) microwire arrays, as well as NeuroNexus’ Matrix platform
arrays, one of the most delicate and complicated commercially-available implants. This Phase II SBIR expands
use of the NeuralGlider inserter for inserting complex, fragile, and flexible penetrating neural electrode arrays
using ultrasonic vibration to reduce insertion force, brain surface dimpling, tissue damage, and bleeding. The
project uses a unique multi-institutional collaboration to obtain scientific data, supporting the benefits of the
NeuralGlider insertion technology. Phase II hypothesis: Ultrasonic micro-vibration improves insertion accuracy
and success, reduces insertion trauma, and improves recording outcomes for penetrating neural electrode
arrays. Specific Aims: Aim 1 - Evaluate implantation trauma and inflammation response through 2-photon
imaging and magnetic resonance imaging. Aim 2 - Demonstrate efficacy of NeuralGlider insertion approach
for ultra-fine, ultra-high-density electrode array designs. Aim 3 - Integrate end user feedback, design upgrades
for coupling options, and conduct Verification and Validation. Aim 4 - Demonstrate improved outcomes with
micro-vibrated insertion.
