Relations of the facial nerve with the retromandibular vein: anatomic study of 132 parotid glands

Abstract

More variations were present in our description than in others. The situation of the rvm alone or associated with other anatomical elements is not a reliable landmark of the situation of a tumour either in the superficial part or in the deep part of the parotid gland in relation to the facial nerve. Some authors considered that the predictive value of these anatomical landmarks was near 65%.

Anatomic variability in the relation between the retromandibular vein and the facial nerve: a case report, literature review and classification

“…Consequently, the RV was found following the established as normal pattern, lying deep (medial) to the FN trunk or/and branches in 88.17%, while in 11.83% the RV topography presented variability. The vein may be found lying anterior to the FN, while it could be present bilaterally to the FN, either as a "ring" around the nerve branches or as a "fork" formed by the RV branches, as it occurs in our case [2,3,19].…”

“…Furthermore, some cases of encountered variants have been reported in the literature independently [2][3][4]. Bhattacharyya and Varvares [4] observed a case, in which the inferior division of FN was encountered deep to the RV during parotid surgery, whereas cases in which the FN and its branches were found encircled by venous rings [19] or "forked" between the MV and its divisions have also been reported, found either during cadaver dissection or surgery [2,3].…”

“…The most important risk while intervening in the parotid gland is injuring the FN [3,19]. Consequently, location of the lesion in relation to the FN must be evaluated preoperatively in order to minimize the potential complications.…”

“…The retromandibular vein (RV) (temporomaxillary or posterior facial vein) has been reported as one of the anatomical landmarks that locate and protect the facial nerve (FN) during surgery [3,19]. The most important risk while intervening in the parotid gland is injuring the FN [3,19].…”

“…Consequently, location of the lesion in relation to the FN must be evaluated preoperatively in order to minimize the potential complications. As the direct visualising of the FN using imaging techniques is inefficient [1,15,19], the RV can be used as a reliable landmark during magnetic resonance imaging (MRI) [1,7,9], computed tomography (CT) scanning [7,15] and sonography [8] in order to identify the tumour location inside the parotid gland. Other anatomical landmarks, such as the Conn's arc [5], the Utrecht and the FN line [1,15] could also be used, while the parotid duct criterion has been suggested additionally to the RV [9], assisting in the localisation of the parotid gland tumours, preoperatively.…”