Effect of 810 nm light on nerve regeneration after autograft repair of severely injured rat median nerve

• Published in: Lasers in surgery and medicine 2011-11, Vol.43 (9), p.901-906
• Main Authors: Moges, Helina, Wu, Xingjia, McCoy, Jennifer, Vasconcelos, Olavo M., Bryant, Howard, Grunberg, Neil E., Anders, Juanita J.
• Format: Article
• Language: English
• Subjects: Animals; autograft; autologous nerve graft; compound muscle action potential; Female; fibrin glue; grip strength test; Injury Severity Score; Lasers, Semiconductor - therapeutic use; light therapy; Median Nerve - injuries; Median Nerve - surgery; Nerve Regeneration - radiation effects; peripheral nerve injury; Peripheral Nerves - transplantation; Rats; Rats, Sprague-Dawley
• ISSN: 0196-8092; 1096-9101
• DOI: 10.1002/lsm.21117

Background and Objective Destruction of large segments of peripheral nerves results in chronic loss of sensation and paralysis. For this type of severe injury, the defect can be bridged by nerve grafts. However, even with state‐of‐the‐art microsurgical techniques, there is minimal recovery of sensation and motor function. Light therapy (LT) has been shown to improve functional outcome after surgical intervention to repair injured nerves using different techniques. Our objective was to investigate the effect of LT on peripheral nerve regeneration and function after severe median nerve injury and microsurgical autologous nerve graft repair using fibrin glue. Study Design/Materials and Methods Adult female Sprague Dawley rats were used for this study. A 6–7 mm segment of the median nerve was excised and sural nerve segments from the same animal were used to bridge the gap using fibrin‐based sealant. There were three experimental groups: control, autograft (AG), and autograft + LT (AG + LT). The AG + LT group received LT at the surgery site for 14 consecutive days using an 810 nm wavelength diode laser. Functional recovery was assessed bi‐weekly by the grip strength test. Compound muscle action potential (CMAP) measurements were taken pre‐injury and at 16 weeks post‐surgery. Optical density measurement of S‐100 immunoreactivity was done on the transplanted segment of the nerve. Results The AG + LT group had faster functional recovery of grip strength (P