title: Effect of 810 nm light on nerve regeneration after autograft repair of severely injured rat median nerve.
abstract: 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.
  
  
  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 < 0.05), shorter CMAP latency (P < 0.05), and higher S-100 immunoreactivity (P = 0.0213) when compared to the AG group. However, at 15 weeks, grip strength in both the AG and AG + LT groups, while significantly improved, were still below control levels.
  
  
  CONCLUSIONS
  These results suggest that LT can accelerate functional recovery and improve the quality of nerve regeneration after autograft repair of severely injured peripheral nerves.
authors: Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA.
authors: Helina
authors: H
authors: Moges
authors: Xingjia
authors: X
authors: Wu
authors: Jennifer
authors: J
authors: McCoy
authors: Olavo M
authors: OM
authors: Vasconcelos
authors: Howard
authors: H
authors: Bryant
authors: Neil E
authors: NE
authors: Grunberg
authors: Juanita J
authors: JJ
authors: Anders
mesh_terms: D000818:Animals; D005260:Female; D015601:Injury Severity Score; D054023:Lasers, Semiconductor / Q000627:therapeutic use*; D008475:Median Nerve / Q000293:injuries* / Q000601:surgery*; D009416:Nerve Regeneration / Q000528:radiation effects*; D010525:Peripheral Nerves / Q000637:transplantation*; D051381:Rats; D017207:Rats, Sprague-Dawley