Peripheral facial palsy: etiology, diagnosis and treatment.

Treatment options for peripheral facial palsy (PFP) are an often discussed problem in neurologic practice. Following a short description of the complex anatomy of the seventh cranial nerve we therefore review possible etiologies in the context of leading clinical signs, with idiopathic PFP or Bell's palsy (BP) being most frequent. A rather typical clinical course of BP allows to focus differential diagnostic workup predominantly on the rapid identification of treatable infections such as with Herpes zoster or Borrelia burgdorferi. Neuroimaging studies are needed only in case of trauma, with slowly developing PFP or in the presence of associated signs and symptoms. As BP is characterized by an overall high rate of spontaneous recovery, major emphasis has to be put on avoiding complications by protecting the eye. Meta-analysis of four randomized controlled studies suggests a marginal benefit of steroids concerning eventual achievement of complete recovery. Beneficial effects of a combination of acyclovir and prednisone have also been claimed. While such therapies may be considered in patients with a presumptive bad prognosis, more general recommendations on medical treatment of BP will have to await further trials.