Surgical anatomy of the rat facial nerve.

Animal models of facial nerve healing and regeneration are becoming increasingly important as new techniques of facial nerve repair and grafting are developed. We have described in detail the peripheral branching pattern of the rat facial nerve and performed axon counts on the main trunk and peripheral branches. Similarities and differences between the human and rat facial nerve are emphasized and the branches of the rat nerve amenable to experimental manipulation are identified. In addition, electrophysiologic data from the rat show a more diffuse pattern of innervation of the face from the individual branches than seen in humans.