Facial Nerve Danger Zones.

Facial nerve injury is one of the most feared complications in surgical rejuvenation of the aging face. Understanding the three-dimensional architecture of the facial soft tissue, the fascial planes that exist within this architectural arrangement, and the danger zones where the facial nerve is situated superficial and adjacent to the planes of dissection commonly used in face-lift techniques, are the keys to safety in preventing motor branch injury. The two-dimensional branching patterns of the marginal and cervical branches of the facial nerve are variable, making it difficult to ascertain exact nerve location when dissecting within the cheek and neck. On a three-dimensional basis, the position and depth of the marginal and cervical branches are constant and predictable. Understanding the three-dimensional anatomy in terms of planes of dissection, and the danger zones where these nerve branches are vulnerable to injury, provides protection against iatrogenic injury when performing surgical rejuvenation of the aging face. These video vignettes provide an overview of the fascial anatomy of the cheek in relation to the facial nerve branches and delineate the regions of the face in which nerve branches are most likely to be injured. Methods to prevent injury are discussed. Furthermore, the vignette defines these danger zones and delineates methods to protect the nerve branches.