# Comparison of Photochemically Sealed Commercial Biomembranes for Nerve Regeneration

## TL;DR

This study compares different commercial biomembranes used with a light-based bonding method for nerve repair in rats, finding that they perform similarly to traditional surgical repair.

## Contribution

The study introduces the use of photochemical tissue bonding with commercial collagen membranes as a viable alternative to microsurgical suture repair for nerve regeneration.

## Key findings

- No significant differences in functional recovery scores were found between surgical repair and photochemical bonding methods.
- Histological analysis showed inflammation that decreased over time, with similar axon regeneration across all groups.
- PTB with commercial membranes like AML and SIS showed improved outcomes over time.

## Abstract

Peripheral nerve injuries affect 13–23 per 100,000 people annually in the U.S. and often result in motor and sensory deficits. Microsurgical suture repair (SR) is the standard treatment but is technically challenging and associated with complications. Photochemical tissue bonding (PTB), which uses light and a photoactivated dye to bond collagenous tissues, offers a promising alternative. We compared PTB with commercially available collagen membranes for SR and PTB using cryopreserved human amnion (HAM) in a rat sciatic nerve transection model. In total, 75 Lewis rats underwent nerve repair with one of five methods: SR, PTB-HAM, PTB with commercial collagenous membranes (human amnion monolayer (AML), human amnion–chorion–amnion trilayer (ATL), or swine intestinal submucosa (SIS)). Functional recovery was assessed with walking tracks and the Static Sciatic Index (SSI) at days 30, 60, 90, and 120; histological evaluations at days 30 and 120 examined inflammation, axon density, and fascicle structure. No significant differences in SSI scores were found between groups, though PTB-AML and PTB-SIS improved over time. Histology showed inflammation at day 30 that decreased by day 120. Histomorphometry revealed similar axon regeneration across groups. These results suggest that PTB with commercial membranes is a viable alternative to SR.