AbstractWhen a cut nerve, which has been repaired, does not function properly it is usually due to the regenerating axons failing to cross the site of the anastomosis. The axonal regrowth may be blocked either by the presence of granulation tissue between the cut ends of the nerve, or to poor stabilization of the nerve stumps with resultant movement and torsion.In the past, many substances have been utilized to protect these anastomosis, most with unfavorable results. The most popular material used today for nerve protection is silastic sheeting which appears to offer some protection without having any major undesirable side effects.Gibb in a previous article, suggested that autogenous vein may be an excellent material for the protection of facial nerve anastomosis. It is readily available, easily tailored and completely physiologic. We felt his proposal had merit, but that it first should be evaluated in an animal model before embarking on a clinical trial.Eighteen dog facial nerves were severed. In six animals (control group) the nerve was repaired with three 7/0 silk sutures in neurolemmal sheath. In the second six, after the nerve sheath was repaired, a section of post auricular vein was wrapped around the anastomosis, being held in place with 7/0 silk sutures. In the remaining six animals, prior to repairing the severed nerve, a tube‐like section of post‐auricular vein was slipped around the proximal segment of the nerve, then after the nerve anastomosis was completed, the vein tube was pulled down over the anastomosis and held in place with 7/0 silk suture.Animals in each group were sacrificed at one, two and three months, in addition, three animals in each group were kept until maximum return of facial function occurred.Clinical evaluation revealed that the animals which had their nerve anastomosis protected with the vein tube or vein sheeting, had more complete return of facial function than the control group.Histological sections showed the vein still to be identifiable during the first two postoperative months, after this is became lost in the general fibrous reaction that occurred around the anastomosis. There was no difference between the groups in the amount of granulation tissue or fibroblasts in the area of the anastomosis. It appears that a careful anastomosis of the neurolemmal sheath will prevent granulations from entering the nerve as effectively as the vein tube; however, we felt that the additional stabilizing effect of the vein tube contributed to the improved results in the sheated animals.It appears that autogenous vein is a safe substance for the protection of facial nerve anastomosis, and is suitable for clinical use.