Nerve Transfers for Facial Palsy Following Skull Base Surgery

Background: Nerve transfers are indicated when the main trunk of the facial nerve is damaged but the distal nerve branches and mimetic muscles remain viable. Hypoglossal-facial nerve transfer has been widely used for facial reanimation; however, the masseteric nerve has recently been shown to be useful as a primary modality for facial reanimation. We present our experience with nerve transfers for patients with irreversible facial palsy after skull base surgery.

Methods: Between 2009 and 2012, seven patients with irreversible facial palsy after extirpation of skull base tumors were treated with nerve transfers. Masseteric-facial nerve transfer combined with cross-face nerve graft (CFNG) was performed in five cases, and end-to-side hypoglossal-facial nerve transfer combined with CFNG was done in two cases. The ages of the patients ranged from 30 to 71 years (mean: 57 years), and all were women. The longest duration of paralysis was 24 months. Follow-up periods were from 10 to 40 months (mean: 25 months).

Results: Four of five patients with masseteric-facial nerve transfer regained facial movements within 5 months. They were able to produce a voluntary smile. Masseter muscle contraction was preserved in every patient. One patient with end-to-side hypoglossal-facial nerve transfer regained facial movement in 8 months. However, no spontaneous smile was achieved in the seven patients during the follow-up period.

Conclusions: Masseteric-facial nerve anastomosis is an alternative method for patients with irreversible facial palsy and still viable mimetic muscles. The advantage of the masseteric nerve is a sufficient nerve length without the need for interpositional nerve grafting for masseteric-facial anastomosis, and this accelerates facial muscle reinnervation. Direct end-to-side hypoglossal-facial nerve transfer is also an alternative method if ipsilateral Vth nerve cannot be used. The strategy for the cross-face nerve grafting seems to be the key for spontaneous smiling.