MRI and Ultrasound Visualization of a Nerve Repair Implant Containing Nitinol.

Background: Nerve Tape is a novel nerve repair device containing nitinol microhooks that provide sutureless attachment for nerve coaptation. This study evaluated visualization of Nerve Tape on magnetic resonance imaging (MRI) and ultrasound, with the objective of exploring its potential as an imaging marker for localizing nerve repair sites.

Methods: Phantom imaging experiments were first conducted to assess the visibility of Nerve Tape on MRI and ultrasound.

Biomechanical Testing of a Novel Device for Sutureless Nerve Repair.

Suboptimal nerve end alignment achieved with conventional nerve repair techniques may contribute to poor clinical outcomes. In this study, we introduce Nerve Tape, a novel nerve repair device that integrates flexible columns of Nitinol microhooks within a biologic backing to entubulate, align, and secure approximated nerve ends. This study compares the repair strength of Nerve Tape with that of conventional microsuture repairs.

Microneedle cuff electrodes for extrafascicular peripheral nerve interfacing.

Objective: The work presented here describes a new tool for peripheral nerve interfacing, called the microneedle cuff (μN-cuff) electrode.

Approach: μN arrays are designed and integrated into cuff electrodes for penetrating superficial tissues while remaining non-invasive to delicate axonal tracts.

Main Results: In acute testing, the presence of 75 μm height μNs decreased the electrode-tissue interface impedance by 0.

Regenerative scaffold electrodes for peripheral nerve interfacing.

Advances in neural interfacing technology are required to enable natural, thought-driven control of a prosthetic limb. Here, we describe a regenerative electrode design in which a polymer-based thin-film electrode array is integrated within a thin-film sheet of aligned nanofibers, such that axons regenerating from a transected peripheral nerve are topographically guided across the electrode recording sites. Cultures of dorsal root ganglia were used to explore design parameters leading to cellular migration and neurite extension across the nanofiber/electrode array boundary.

Characterization of a composite injury model of severe lower limb bone and nerve trauma.

Severe extremity trauma often results in large zones of injury comprising multiple types of tissue and presents many clinical challenges for reconstruction. Considerable investigation is ongoing in tissue engineering and regenerative medicine therapeutics to improve reconstruction outcomes; however, the vast majority of musculoskeletal trauma models employed for testing the therapeutics consist of single-tissue defects, offering limited utility for investigating strategies for multi-tissue repair. Here we present the first model of composite lower limb bone and nerve injury, characterized by comparison to well-established, single-tissue injury models, using biomaterials-based technologies previously demonstrated to show promise in those models.

Highly-compliant, microcable neuroelectrodes fabricated from thin-film gold and PDMS.

Bio-electrodes have traditionally been made of materials such as metal and silicon that are much stiffer than the tissue from which they record or stimulate. This difference in mechanical compliance can cause incomplete or ineffective contact with the tissue. The electrode stiffness has also been hypothesized to cause chronic low-grade injury and scar-tissue encapsulation, reducing stimulation and recording efficiency.

Thin-film enhanced nerve guidance channels for peripheral nerve repair.

It has been demonstrated that nerve guidance channels containing stacked thin-films of aligned poly(acrylonitrile-co-methylacrylate) fibers support peripheral nerve regeneration across critical sized nerve gaps, without the aid of exogenous cells or proteins. Here, we explore the ability of tubular channels minimally supplemented with aligned nanofiber-based thin-films to promote endogenous nerve repair. We describe a technique for fabricating guidance channels in which individual thin-films are fixed into place within the lumen of a polysulfone tube.