![]() ![]() Distal nerve identification techniques are rarely described in the literature, these being adapted, as necessary, by the surgeon, depending on the localisation of the neoplasm, and approach the isolation of the nerve beginning from any of its peripheral branches. A branch of the postauricular artery is usually encountered just lateral to the nerve. The nerve is always lateral to this plane and passes obliquely across the styloid process. (d) The styloid process itself can be palpated superficial to the stylomastoid foramen and just superior to it. (c) The anterior, superior aspect of the posterior belly of the digastric muscle is inserted just behind the stylomastoid foramen. Unfortunately this groove is filled with fibrofatty lobules that often mimic the trunk of the facial nerve which can lie as much as 1 cm deep to this landmark. This forms a palpable groove leading directly to the stylomastoid foramen. (b) Just deep to the cartilaginous pointer is a reliable bony landmark formed by the curve of the bony external meatus and its abutment with the mastoid process. There are four anatomical landmarks leading to the identification of the trunk of the facial nerve as it leaves the stylomastoid foramen: (a) The cartilaginous external auditory meatus forms a ‘pointer’ at its anterior inferior border indicating the direction of the nerve trunk. Facial nerve is identified by means of proximal surgical technique aimed at isolating proximally the main nerve trunk anywhere between stylomastoid foramen and parotid gland entry. ![]() They are covered by glandular acini and rests on the aponeurosis of the masseter muscle, with its temporal and zygomatic component running to a thin adipose layer upon its emergency from the cranial pole of the gland. The anatomical evaluations reveal that all the five branches run in the substance of parotid isthmus dividing superficial and deep lobes of the parotid. The superior temporofacial branch runs upwards and medially and is generally larger. The most frequent morphology of the facial nerve is reported, in the literature, to be dichotomous, with cervicofacial and temporofacial divisions further dividing into temporal, zygomatic, buccal, marginal mandibularis and cervical branches. Whether the condition is benign or malignant and if the facial nerve is not involved preoperatively, its preservation is important for both aesthetic and functional outcome of the surgery. Parotid gland surgery is technique sensitive because of the close relationship of the gland with the extra-cranial facial nerve which is a motor supply to the muscles of facial expression. The decision to resort to the identification of the buccal nerve is supported by the regular course and adequate size of this branch of facial nerve in its peripheral area co-located with stenson’s duct, which enable it to be easily identified during surgery. Distal exploration of the buccal branch was undertaken only in one case, on account of difficulty in locating the main trunk intraoperatively, due to the presence of a post inflammatory fibrosis. The technique mainly chosen was conventional proximal nerve identification technique in 16 cases. The present report deals with personal clinical experience, describing both the techniques for detection of the facial nerve in 17 cases reported. There are reports in the literature on distal nerve identification techniques, either as a choice or in cases where proximal nerve identification is difficult. Facial nerve is generally located by means of a proximal surgical identification technique aimed at identifying the facial nerve at its point of exit from the stylomastoid foramen to its entry into the posteromedial surface of parotid gland. One of the most technique sensitive surgeries in the maxillofacial region is the parotid gland surgery owing to the close relation between the gland and the extra-cranial course of facial nerve. ![]()
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