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

BACKGROUND

The retromandibular vein (rmv) is an important anatomical element, in radiology to localise a tumor in the parotid gland in relation to the facial nerve, and in surgery as a landmark to dissect the facial nerve and its branches. The aim of this study was to give a precise description of the anatomic variations of the relations of the facial nerve with the rmv.

METHODS

One hundred and thirty-two parotid glands have been dissected by pre-auricular route. The rmv, the facial nerve trunk and its branches have been dissected and described. The relations of the facial nerve with the rmv have been noted in each case.

RESULTS

The rmv was medial to the nerve in 65.2% and lateral in 13% to the nerve. In 6.8% the nerve was placed between a superficial and a deep venous plane.

DISCUSSION

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%.