The course of the temporal branch of the facial nerve in the periorbital region

Purpose: This study identified the terminal temporal and zygomatic branches of the facial nerve as they enter the orbicularis oculi muscle and related these branches to identifiable surface markings. Materials and Methods: The temporal and zygomatic branches of the facial ne rve mere dissected from 5 preserved cadavers (10 sides). The most superior temporal branch entering the orbicularis oculi muscle was identified and re lated to the lateral canthus of the eye. A vertical line was passed through this point so that the line was equidistant from the nasal tip and chin po int. A line perpendicular to the vertical line through the lateral canthus sen ed as the horizontal scale. Vertical and horizontal lines through the l ateral canthus were used to establish the anatomic relationship between the lateral canthus and the branch of the temporal nerve entering the orbicula ris oculi muscle. Results: The temporal branch was an average of 2.85 +/- 0.69 cm superior to the lateral canthus and an average of 2.54 +/- 0.43 cm lateral to the late ral canthus as it courses into the orbicularis oculi muscle. At the lateral border of the orbicularis oculi muscle, where the temporal and zygomatic n erves insert into the muscle, the mean vertical distance between the tempor al and zygomatic nerves was 1.72 +/- 0.62. cm. Conclusion: Incisions superior or inferior and parallel to the course of th e facial nerve, can provide access to the fronto zygomatic suture and the s uperior and lateral orbit without damaging its branches, (C) 2001 American Association of Oral and Maxillofacial Surgeons.