The neurologist's dilemma: a comprehensive clinical review of Bell's palsy, with emphasis on current management trends

Abstract

Background: Recent advances in Bell's palsy (BP) were reviewed to assess the current trends in its management and prognosis.

Material/methods: We retrieved the literature on BP using the Cochrane Database of Systematic Reviews, PubMed, and Google Scholar. Key words and phrases used during the search included 'Bell's palsy', 'Bell's phenomenon', 'facial palsy', and 'idiopathic facial paralysis'. Emphasis was placed on articles and randomized controlled trails (RCTs) published within the last 5 years.

Results: BP is currently considered the leading disorder affecting the facial nerve. The literature is replete with theories of its etiology, but the reactivation of herpes simplex virus isoform 1 (HSV-1) and/or herpes zoster virus (HZV) from the geniculate ganglia is now the most strongly suspected cause. Despite the advancements in neuroimaging techniques, the diagnosis of BP remains one of exclusion. In addition, most patients with BP recover spontaneously within 3 weeks.

Conclusions: Corticosteroids are currently the drug of choice when medical therapy is needed. Antivirals, in contrast, are not superior to placebo according to most reliable studies. At the time of publication, there is no consensus as to the benefit of acupuncture or surgical decompression of the facial nerve. Long-term therapeutic agents and adjuvant medications for BP are necessary due to recurrence and intractable cases. In the future, large RCTs will be required to determine whether BP is associated with an increased risk of stroke.

Figure 1

Sir Charles Bell (Used with permission from Van Gijn, 2011).

Figure 2

Drawing representing a man with Bell’s palsy showing right facial hemiparalysis.

Figure 3

(A) Schematic diagram of the motor innervation of the facial nerve. (B) Schematic diagram of the parasympathetic innervation of the facial nerve.

Figure 4

Proposed algorithm for the management of severe Bell’s palsy. FP, facial palsy; EMG, electromyography; D15, fifteen days after onset of palsy (Redrawn and modified with permission from Bodenez et al., 2010).