A simple method for safe identification of the facial nerve using palpable landmarks

Area of Science:

• Anatomy
• Surgical Anatomy
• Head and Neck Surgery

Background:

• The facial nerve (CN VII) is crucial in facial expression and motor control.
• Accurate identification of the facial nerve trunk is vital for preventing injury during parotid gland surgery.
• Existing methods for facial nerve identification can be time-consuming or lack precision.

Purpose of the Study:

• To evaluate the efficacy of external palpable landmarks for rapid and safe identification of the main facial nerve trunk.
• To determine the accuracy of these landmarks in guiding surgical dissection.

Main Methods:

• A prospective anatomical dissection study was conducted on 40 human cadaver heads (79 facial nerves).
• Dissection involved a standardized skin incision within a defined triangle of landmarks (TMJ, mastoid process, mandibular angle).
• Time to nerve identification and the distance between predicted and actual nerve positions were measured.

Main Results:

• The facial nerve trunk was successfully identified in all dissected specimens.
• The mean time for identification was consistent between prosectors (144 vs. 148 seconds).
• The average distance between the predicted and actual facial nerve position was minimal (1.42 mm).

Conclusions:

• The proposed external palpable landmarks provide a fast and safe method for locating the facial nerve trunk.
• These landmarks can significantly assist surgeons operating in the parotid region.
• This technique enhances surgical safety and efficiency in procedures involving the facial nerve.