IN-VITRO LASER NERVE REPAIR - PROTEIN SOLDER STRIP IRRADIATION OR IRRADIATION ALONE

Background. This study investigated the potential of sutureless nerve repair using two promising laser fusion methods: direct 2 mu m irradia tion of the epineurium, and protein solder assisted epineurial fusion using a 800 nm laser, Materials and methods. Laser anastomosis of the rat sciatic nerve was performed in vitro without stay sutures in tno g roups of sis animals, In the first group, direct laser fusion used a p ulsed Cr,Tm:YAG laser, In the second group an albumin-based fluid sold er containing the dye indocyanine green nas applied to the epineurium, then irradiated with a diode laser, These two techniques were compare d with regards to coaptation success and axonal damage, Results, Direc t laser welding produced weak bonds despite microscopic investigation of the il radiated nerves showing fusion of the epineurium. The unsati sfactory bonding can be attributed to poor tissue overlap and insuffic ient protein in the thin epineurium denaturation of underlying axons w as also observed, In contrast, the laser solder method produced succes sful welds with greatly reduced atonal damage, and significantly impro ved the tensile strength, Conclusions, This study confirmed the techni cal possibilities of sutureless nerve anastomosis. Laser activated sol ders enable stronger bonds, by the addition of protein to the anastomo sis site, and less thermal damage to underlying tissue through selecti ve absorption of laser energy by dye in the solder, Further in vivo st udies are required before drawing final conclusions.