Identification of Facial Nerve During Parotidectomy: A Combined Anatomical & Surgical Study

Abstract

To find out the most easily identifiable and anatomically consistent landmark for identification of facial nerve during parotid surgery. Ten cadaveric dissections and ten live parotid surgeries for different types of parotid tumours were done. Cadaveric dissection was performed in the Department of Anatomy and the surgeries were done in the Department of ENT and Head and Neck surgery of R. G. Kar Medical College of Kolkata. The distance of the facial nerve trunk from three most commonly used landmarks (viz., tympanomastoid suture, tragal pointer and posterior belly of digastric muscle) was measured in both cadaver and live patients. The ease of identification of the nerve trunk using each of the landmarks, particularly during live surgery was also assessed. The mean distance of the tympanomastoid suture from the facial nerve trunk was 3.5 mm (cadaver) and 3.87 mm (live surgery), the tragal pointer was found to be at a mean distance of 16.61 mm (cadaver) and 16.36 mm (live surgery) and in case of the posterior belly of digastric muscle it was 7.41 mm (cadaver) and 8.03 mm (live surgery). During live surgery the posterior belly of digastric was found to be the most easily identifiable landmark with a consistent anatomical relationship with the nerve trunk. The posterior belly of digastric muscle is the most easily identifiable and a very consistent landmark for facial nerve dissection during parotidectomy. When supplemented with the tragal pointer, accuracy in identifying the facial nerve trunk is very high, thereby avoiding inadvertent injury to the nerve trunk.

Terminal Branching Pattern of Facial Nerve Seen in Adult Cadavers: An Anatomical Study

“…This incision was extended from 10 mm superior to the tragal cartilage to a point 20 mm inferior to the angle of the mandible, to avoid any damage to the marginal mandibular nerve. 10 Once the incision was given, skin flap was raised and further, subcutaneous tissue was dissected.…”

Identification of the Facial Nerve Trunk During Superficial Parotidectomy by Trident Landmark

“…This clearly indicates to the fact that parotid gland surgery is purely an anatomical dissection. (14) A detailed understanding of the operative anatomical landmarks during parotid surgery and a meticulous surgical exploration can help safeguarding the facial nerve trunk (FNT) and its branches. (15) Landmarks for facial nerve trunk identification was described in the earlier part of the previous century as a result of the general awareness of poor surgical results (Wong, 2001).…”

Facial Paralysis after Trauma: A Simplified Method to Find and Repair the Facial Nerve

“…Urgent surgical intervention on the time of the trauma, on the other hand, provides a better surgical field without no fibrosis or synechiae and primary repair or cable grafting of the facial nerve brings out better cosmesis and functional results. 10,11 The middle deep temporal nerve branches can be identified on the deep side of the temporalis, within 9 to 12 mm posterior to the jugal point of the zygoma and utilized for facial reanimation. This technique may reanimate the facial muscles with independent activation.…”