Development of an Infrared Nerve Stimulator

Greg Wigger, Chris Tedder, and Melanie Gault

Advised by:Dr. Duco Jansen, Ph.D.

The Problem

This requires a reliable stimulation modality to gain better control over neural signals.

There is a need for an implantable device that will reliably stimulate individual nerve fascicles

Our Solution: Infrared Stimulation

Infrared StimulationSame advantages as electrical

stimulation, but: Less damaging to nerve Artifact free Spatially selective

Electrical StimulationHas fundamental shortcomings that

create a need for an alternative Contact can cause permanent damage

to nerve Stimulation artifact Hard to selectively stimulate

Rat Sciatic Nerve

Electrical Stimulator

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AP

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Rat Sciatic Nerve

Electrical Stimulator

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Fiber Coupled Laser

Rat Sciatic Nerve-0.1

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Fiber Coupled Laser

Optical Fiber

Group ObjectiveDevelop an infrared nerve stimulator

containing optical fibers running parallel to the nerve fibers Create a single fiber prototype Create a four fiber prototype embedded in

a cuff to be wrapped around entire nerve bundle

Two models will be tested:

Fiber with angled mirror

Fiber polished at 45 degree angle

Past Work

IUCAC training for rat experimentation Introduction to Rats, Working with the

IACUC:non-VA version, and Post-Procedure care of mice and rats in research: minimizing pain and distress

Polished a fiber at 45 degrees Used varying sized grit paper and

worked our way down to 1 µm

Past Work (Continued) Observed beam profile of polished optic

fiber

Obtained materials for mirror deign mirror, nylon tube

Submitted machine shop order for 45 degree angled tube insert

Current Work

Construction of proof-of-concept prototype for mirror reflection within the week

Meet with the guys at the machine shop to get the optical fiber fitted into the prototype.

Future Work

Power output analysis for both side-firing techniques

Animal studies of both prototypes? Development of nerve cuff design

with 4 side-firing fibers Exploration of PDMS for biomaterial Customized building of best side-

firing fiber (custom ordered parts, smaller size, etc.)