Trans-mastoid facial nerve localisation for malignant neoplasms confined to the parotid gland.

Up to 32% of parotid neoplasms are malignant, and treatment for resectable parotid carcinomas remains primarily surgical. Resection is centred round the identification and preservation (where possible) of the main trunk of the facial nerve. Limited dissection of the temporal bone and identification of the facial nerve proximally in the mastoid portion can facilitate resection for all parotid carcinomas that occur in the preauricular portion of the gland. Dissection in the narrow space between the ear or base of the skull and the tumour reduces the risk of tumour spillage, and the margin for resection is optimised. Intramastoid localisation of the facial nerve allows a posterior approach, and access to the dissection plane lies medial to the nerve. We describe the technique in a series of eight patients undergoing resection for parotid malignancies. In our experience the technique promotes adequate resection margins, reduces the risk of tumour spillage, and allows better access for nerve grafting if the facial nerve has to be sacrificed.