Facial nerve management in patients with malignant skull base tumors

Abstract

Introduction: The course of the facial nerve through the cerebellopontine angle, temporal bone, and parotid gland puts the nerve at risk in cases of malignancy. In contrast to Bell's palsy, which presents with acute facial paralysis, malignancies cause gradual or fluctuating weakness.

Methods: We review malignancies affecting the facial nerve, including those involving the temporal bone, parotid gland, and cerebellopontine angle, in addition to metastatic disease. Intraoperative management of the facial nerve and long term management of facial palsy are reviewed.

Results: Intraoperative management of the facial nerve in cases of skull base malignancy may involve extensive exposure, mobilization, or rerouting of the nerve. In cases of nerve sacrifice, primary neurorrhaphy or interposition grafting may be used. Cranial nerve substitution, gracilis free functional muscle transfer, and orthodromic temporalis tendon transfer are management options for long term facial paralysis.

Conclusion: Temporal bone, parotid gland, and cerebellopontine angle malignancies pose a tremendous risk to the facial nerve. When possible, the facial nerve is preserved. If the facial nerve is sacrificed, static and dynamic reanimation strategies are used to enhance facial function.

Keywords: Acoustic neuroma; Facial paralysis; Facial reanimation; Gracilis; Masseteric facial nerve transfer; Modified selective neurectomy; Synkinesis; Temporal bone malignancy; Temporalis tendon transfer.