J Korean Med Sci.  2010 Aug;25(8):1228-1230. 10.3346/jkms.2010.25.8.1228.

Double Facial Nerve Trunk Emerged from the Stylomastoid Foramen and Petrotympanic Fissure: A Case Report

• Kilic C
• Kirici Y
• Kocaoglu M

• KMID: 1714048
• DOI: http://doi.org/10.3346/jkms.2010.25.8.1228

Abstract

There are several studies concerning branches of the facial nerve, but we encountered less information about the trunk of the facial nerve in the literature. During the routine dissection of a 65-yr-old Caucasian male cadaver, double facial nerve trunk emerged from the stylomastoid foramen and petrotympanic fissure were encountered. Because of an extremely rare variation, we presented this case report. In addition this cadaver had two buccal plexuses. These plexuses and other branches were formed to structures like to polygon. These anatomic peculiarities were described, photographed and illustrated. Finally, magnetic resonance imaging was performed by using 1.5T scanner to this cadaver. The facial nerve trunk can be damaged during surgical procedures of the parotid gland tumours and submandibular region. Surgeons who are willing to operate on this area should be aware of the possible anatomical variations of the facial nerve trunk.

Keyword

Facial Nerve Trunk; Variation

MeSH Terms

Aged
Cadaver
Facial Nerve/*anatomy & histology/surgery
Humans
Magnetic Resonance Imaging
Male
Parotid Gland/innervation
Temporal Bone/*innervation

Figure

• 

  Fig. 1 (A) The ramus of the facial nerve exited from different foramen in left side (lateral view). (B) The schematic drawing. The stylomastoid foramen (Sf); petrotympanic fissure (Pf); first buccal (Bp1) plexus; temporofacial (Tr) and cervicofacial (Cr) rami; temporal (T), zygomatic (Z), buccal (B), marginal mandibular (M) and cervical (C) branches of the facial nerve.

• 

  Fig. 2 (A) The two buccal plexuses fromed like to polygon in left side (lateral view). (B) The schematic drawing. The stylomastoid foramen (Sf); petrotympanic fissure (Pf); first (Bp1) and second buccal (Bp2) plexuses; temporofacial (Tr) and cervicofacial (Cr) rami; temporal (T), zygomatic (Z), buccal (B), marginal mandibular (M) and cervical (C) branches of the facial nerve.

• 

  Fig. 3 An oblique sagittal T1-weighted magnetic resonance image shows temporofacial and cervicofacial rami of the facial nerve emerging through the petrotympanic fissure and stylomastoid foramen, respectively. The temporofacial (Tr) and cervicofacial (Cr) rami of the facial nerve.

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