A Review of Facial Nerve Anatomy

An intimate knowledge of facial nerve anatomy is critical to avoid its inadvertent injury during rhytidectomy, parotidectomy, maxillofacial fracture reduction, and almost any surgery of the head and neck. Injury to the frontal and marginal mandibular branches of the facial nerve in particular can lead to obvious clinical deficits, and areas where these nerves are particularly susceptible to injury have been designated danger zones by previous authors. Assessment of facial nerve function is not limited to its extratemporal anatomy, however, as many clinical deficits originate within its intratemporal and intracranial components. Similarly, the facial nerve cannot be considered an exclusively motor nerve given its contributions to taste, auricular sensation, sympathetic input to the middle meningeal artery, and parasympathetic innervation to the lacrimal, submandibular, and sublingual glands. The constellation of deficits resulting from facial nerve injury is correlated with its complex anatomy to help establish the level of injury, predict recovery, and guide surgical management.

KEYWORDS

Extratemporal - intratemporal - facial nerve - frontal nerve - marginal mandibular nerve

REFERENCES

• 1 O'Rahilly R. On counting cranial nerves.  Acta Anat (Basel). 1988;  133 (1) 3-4
• 2 Steinberg D A. Scientific neurology and the history of the clinical examination of selected motor cranial nerves.  Semin Neurol. 2002;  22 349-356
• 3 Bell C. On the nerves, giving an account of some experiments on their structure and functions, which leads to a new arrangement of the system.  Trans R Soc Lond. 1821;  3 398
• 4 Bell C. The Nervous System of the Human Body. 2nd ed. London; Longman's 1830
• 5 Crosby E C, Dejonge B R. Experimental and clinical studies of the central connections and central relations of the facial nerve.  Ann Otol Rhinol Laryngol. 1963;  72 735-755
• 6 Lang J. Anatomy of the brainstem and the lower cranial nerves, vessels, and surrounding structures.  Am J Otol. 1985;  Suppl 1-19
• 7 May M. Anatomy of the facial nerve (spatial orientation of fibers in the temporal bone).  Laryngoscope. 1973;  83 1311-1329
• 8 May M. Anatomy for the clinician. In: May M, Schaitkin BM The Facial Nerve. 2nd ed. New York; Thieme 2000: 19-56
• 9 Podvinec M, Pfaltz C R. Studies on the anatomy of the facial nerve.  Acta Otolaryngol (Stockh). 1976;  81 173-177
• 10 Harris W D. Topography of the facial nerve.  Arch Otolaryngol. 1968;  88 264-267
• 11 Kukwa A, Czarnecka E, Oudghiri J. Topography of the facial nerve in the stylomastoid fossa.  Folia Morphol (Warsz). 1984;  43 (4) 311-314
• 12 Sunderland S. The structure of the facial nerve.  Anat Rec. 1953;  116 147-165
• 13 Wysocki J. Correlations between topography of the main structures of the temporal bone and the location of the sigmoid sinus [in Polish].  Otolaryngol Pol. 1998;  52 287-290
• 14 Fisch U, Esslen E. Total intratemporal exposure of the facial nerve. Pathologic findings in Bell's palsy.  Arch Otolaryngol. 1972;  95 335-341
• 15 Nakashima S, Sando I, Takahashi H, Fujita S. Computer-aided 3-D reconstruction and measurement of the facial canal and facial nerve. I. Cross-sectional area and diameter: preliminary report.  Laryngoscope. 1993;  103 1150-1156
• 16 Hunt J R. On herpetic inflammation of the geniculate ganglion. A new syndrome and its complications.  J New Ment Dis. 1907;  34 73-96
• 17 Rouviere H, Delmas A. Nerfs de la tet et du cou. In: Anatomie Humaine: Descriptive Topographique et Functionnelle. Paris; Masson 1985: 276
• 18 Hitselberger W E, House W F. Acoustic neuroma diagnosis: External auditory canal hypesthesia as an early sign.  Arch Otolaryngol. 1966;  83 218-221
• 19 Wilhelmi B J, Mowlavi A, Neumeister M W. The safe face lift with bony anatomic landmarks to elevate the SMAS.  Plast Reconstr Surg. 2003;  111 1723-1726
• 20 Davis R A, Anson B J, Puddinger J M, Kurth R E. Surgical anatomy of the facial nerve and parotid gland based upon study of 350 cervical facial halves.  Surg Gynecol Obstet. 1956;  102 385-412
• 21 Baker D C, Conley J. Avoiding facial nerve injuries in rhytidectomy. Anatomical variations and pitfalls.  Plast Reconstr Surg. 1979;  64 781-795
• 22 Pitanguy I, Ramos A S. The frontal branch of the facial nerve: the importance of its variations in face lifting.  Plast Reconstr Surg. 1966;  38 352-356
• 23 Stuzin J M, Wagstrom L, Kawamoto H K, Wolfe S A. Anatomy of the frontal branch of the facial nerve: the significance of the temporal fat pad.  Plast Reconstr Surg. 1989;  83 265-271
• 24 Gosain A K, Sewall S R, Yousif N J. The temporal branch of the facial nerve: how reliably can we predict its path?.  Plast Reconstr Surg. 1997;  99 1224-1233 , discussion 1234-1236
• 25 Sabini P, Wayne I, Quatela V C. Anatomical guides to precisely localize the frontal branch of the facial nerve.  Arch Facial Plast Surg. 2003;  5 150-152
• 26 Dingman R O, Grabb W C. Surgical anatomy of the mandibular ramus of the facial nerve based on the dissection of 100 facial halves.  Plast Reconstr Surg. 1962;  29 266-272
• 27 Seckel B R. Facial Danger Zones: Avoiding Nerve Injury in Facial Plastic Surgery. Saint Louis; Quality Medical Publishers 1993
• 28 Freilinger G, Gruber H, Happak W, Pechmann U. Surgical anatomy of the mimic muscle system and the facial nerve: importance for reconstructive and aesthetic surgery.  Plast Reconstr Surg. 1987;  80 686-690
• 29 Happak W, Burggasser G, Liu J, Gruber H, Freilinger G. Anatomy and histology of the mimic muscles and the supplying facial nerve.  Eur Arch Otorhinolaryngol. 1994;  S85-S86
• 30 Freilinger G, Happak W, Burggasser G, Gruber H. Histochemical mapping and fiber size analysis of mimic muscles.  Plast Reconstr Surg. 1990;  86 422-428
• 31 Happak W, Liu J, Burggasser G, Flowers A, Gruber H, Freilinger G. Human facial muscles: dimensions, motor endplate distribution, and presence of muscle fibers with multiple motor endplates.  Anat Rec. 1997;  249 276-284
• 32 Bischoff E PE. Microscopic analysis of the anastomosis between the cranial nerves. In: Sacks EJ, Valtin EW Hanover, NH; University Press of New England 1977
• 33 Norris C W, Proud G O. Spontaneous return of facial motion following seventh cranial nerve resection.  Laryngoscope. 1981;  91 211-215
• 34 Conley J J. Accessory neuromuscular pathways to the face.  Trans Am Acad Ophthalmol Otolaryngol. 1964;  68 1064-1067
• 35 Banfai P. Applied anatomy of the facial nerve. I. Nuclei, supranuclear connections and peripheral nerve [in German].  HNO. 1976;  24 253-264
• 36 Banfai P. Applied anatomy of the facial nerve. II. Anastomoses [in German].  HNO. 1976;  24 289-294
• 37 Graeber M B, Bise K, Mehraein P. Synaptic stripping in the human facial nucleus.  Acta Neuropathol (Berl). 1993;  86 179-181
• 38 Graeber M B, Lopez-Redondo F, Ikoma E et al.. The microglia/macrophage response in the neonatal rat facial nucleus following axotomy.  Brain Res. 1998;  813 241-253