Laser-assisted nerve repair. Laser-trimming of nerve ends with epineurial suture anastomosis.
Suture repair of cranial and peripheral nerves has reached a maximal level with the use of advanced microneurorrhaphy techniques; however, functional recovery of the repaired nerve is still often unsatisfactory due to misrouted axonal regrowth. Freeze-trimming the nerve ends prior to anastomosis has been shown to significantly improve fascicular alignment and subsequent functional recovery. This study assessed the feasibility of using laser energy to trim the nerve ends prior to suture anastomosis. The 302-nm excimer laser was used to trim the severed sciatic nerve ends prior to anastomosis in 28 rats. Scanning electron and light microscopy, horseradish peroxidase retrograde labeling, nerve conduction velocity, and functional recovery were assessed postoperatively. The excimer laser was able to trim the nerve ends flat thereby facilitating the coaptation and alignment of the nerve ends. Misrouting of axons occurred in both the laser-trim and control groups. Although this technique has theoretical advantages, no statistically significant improvement was demonstrated in this investigation. This may have been in part due to the small sample size, since a small increment of improvement was noted. It is possible, however, with continued refinements in technique that a functional improvement may be seen in subsequent studies.