Spontaneous Regeneration of the Seventh Nerve

Spontaneous recovery of facial function has been reported to occur following radical parotid gland surgery, which includes resection of the facial nerve. One author1in a series of 28 such cases, described spontaneous recovery in over 25%. He proposed that this reinnervation occurred by the establishment of new motor pathways through the fifth cranial nerve. He questioned that recovery following facial nerve reconstructive anastomotic procedures2-4was due to regeneration of the seventh nerve. He further stated that a more logical explanation was that it was due to cross innervation by the fifth nerve. The question has thus been raised as to the actual anatomic pathways involved in these patients demonstrating a spontaneous recovery. In an attempt to answer this, a series of experiments was conducted in the animal research laboratory. Experimentation Ten puppies, one month of age (Fig. 1), were used for the study. No special preoperative preparation