The Diagnosis and Treatment of Idiopathic Facial Paresis (Bell's Palsy).

BACKGROUND

Peripheral facial nerve palsy is the most com- mon functional disturbance of a cranial nerve. 60-75% of cases are idiopathic.

METHODS

This review is based on a selective literature search proceeding from the current, updated German-language guideline on the diagnosis and treatment of idiopathic facial nerve palsy.

RESULTS

The recommended drug treatment consists of prednisolone 25 mg bid for 10 days, or 60 mg qd for 5 days followed by a taper to off in decrements of 10 mg per day. This promotes full recovery (number needed to treat [NNT] = 10; 95% confidence interval [6; 20]) and lessens the risk of late sequelae such as synkinesia, autonomic disturbances, and contractures. Virostatic drugs are optional in severe cases (intense pain or suspicion of herpes zoster sine herpete) and mandatory in cases of varicella-zoster virus (VZV) infection. Corneal protection with dexpanthenol ophthalmic ointment, artificial tears, and a nocturnal moisture- retaining eye shield has been found useful in practice. In cases of incomplete recovery with residual facial weakness, both static and microsurgical dynamic methods can be used to restore facial nerve function.

CONCLUSION

Because 25-40% of cases of facial nerve palsy are not idiopathic, differential diagnosis is very important; key diagnostic methods include a clinical neurological examin- ation, otoscopy, and a lumbar puncture for cerebrospinal fluid examination. High-level evidence supports corticosteroid treatment for the idiopathic form of the disorder.