Facial nerve palsy (面神經麻痹/面癱)

Disruption of the lower motor neurone facial nerve can occur at any point between its brainstem nucleus and the facial musculature.


Bellis (idiopathic) Palsy
Clinical features:
Most common palsy with no identifiable cause although a viral or vascular aetiology postulated. Palsy may be partial or complete.

Management:
Total recovery occurs in 90% of cases. Treatment with steroids or surgical decompression controversial.


Ramsay Hunt Syndrome
Clinical features:
Herpes zoster involvement of the facial nerve with herpetic vesicles on the tympanic membrane, pinna or palate. May present with severe otalgia alone. Auditory and trigeminal nerves may be affected.

Management:
Recovers fully in about 60% of cases. If given early, the antiviral agent aciclovir may enhance recovery. The value of steroids or surgical decompression of the nerve remains unproven.


Temporal bone fracture
Clinical features:
Longitudinal fractures (80%) are associated with a facial palsy in 20% of cases and a conductive deafness. Transverse fractures (20%) are associated with a facial palsy in 50% of cases and a sensorineural deafness. Diagnosis is confirmed by CT scan.

Management:
Exploration of the nerve may be indicated in cases of immediate, complete paralysis but is likely to be followed by deafness.