Anatomic surgical dissection of the extraparotid portion of the facial nerve.

The direction followed by the facial nerve branches beyond their emergence from the ventral, cephalic, and caudal borders of the parotid gland up to the facial muscles has been studied by several anatomists, but no consistent description of them has been given so far. This research, based on the dissection of 30 hemifaces, studies the characteristics of those branches using three points of reference: the intertragal notch, the palpebral lateral commissure, and the labial commissure. Tables showing average length and number of branches have been computed with a statistical level of confidence of 99 percent. No fixed common pattern suitable to represent the distribution of branches of the facial nerve in a model was found, but as a rule, these branches run beneath the superficial musculoaponeurotic system (SMAS) in their path below the zygomatic arch, and approximate emergence points have been identified. In the opinion of the authors, such points may be of more surgical relevance than a theoretical pattern of arborization.