Excerpted by the National Guideline Clearinghouse (NGC):
Each clinical recommendation is rated based on the strength of the evidence. Definitions of the strength of the recommendations (Level A-C, Level U) and quality of the evidence (Class I-Class IV) are presented at the end of the Major Recommendations field.
Steroid-Use for the Treatment of Bell’s Palsy
Because of the absence of sufficiently powered class I studies, the authors conclude that a benefit of steroids in Bell’s palsy has not been definitively established. However, the available evidence supports a level "B" recommendation. Thus, based on the pooled result of class I and class II studies and a relatively benign side effect profile, the authors conclude that steroids are safe and probably effective in improving facial functional outcomes in patients with Bell’s palsy.
Acyclovir for the Treatment of Bell’s Palsy
Because of the absence of class I studies, the authors conclude that a benefit of acyclovir in Bell’s palsy has not been definitively established. However, the available evidence supports a level "C" recommendation. Thus, based on the result of a single class II study and a relatively benign side effect profile, the authors conclude that acyclovir (combined with prednisone) is safe and possibly effective in improving facial functional outcomes in patients with Bell’s palsy.
Facial Nerve Decompression Surgery for the Treatment of Bell’s Palsy
The risk of bias in all studies describing facial outcomes in surgically treated Bell’s palsy patients was too high to support evidence-based conclusions. Additionally, serious complications, including permanent hearing loss, were reported from surgical facial nerve decompression. For these reasons, the authors were unable to develop evidence-based recommendations for the use of facial nerve decompression in patients with Bell’s palsy.
Summary of Practice Recommendations
For patients presenting with Bell’s palsy:
- Early treatment with oral steroids is recommended as probably effective to improve facial functional outcomes (Level B).
- Early treatment with acyclovir in combination with prednisone is recommended as possibly effective to improve facial functional outcomes (Level C).
- There is insufficient evidence to make recommendations regarding the use of facial nerve decompression to improve facial functional outcomes (Level U).
Definitions:
Strength of Recommendations:
Level A. Established as effective, ineffective, or harmful for the given condition in the specified population. Usually, an "A" recommendation requires that the pooled result from two or more distinct class I studies demonstrates a consistent, significant, and important effect.
Level B. Probably effective, ineffective, or harmful for the given condition in the specified population. Usually, a "B" recommendation requires that a single class I study demonstrates a significant and important effect or the pooled result from two or more distinct class II studies demonstrates a consistent, significant, and important effect.
Level C. Possibly effective, ineffective, or harmful for the given condition in the specified population. Usually, a "C" recommendation requires that a single class II study demonstrates a significant and important effect or the pooled result of two or more distinct class III studies demonstrates a consistent, significant, and important effect.
Level U. Data are inadequate or conflicting. Given current knowledge, treatment is unproven and an evidence-based recommendation cannot be made.
Classification of Evidence:
Class I. Evidence provided by a randomized, controlled clinical trial with masked outcome assessment in a representative population. The following are required: a) primary outcomes are clearly defined; b) exclusion and inclusion criteria are clearly stated; c) adequate accounting of dropouts and crossovers with numbers sufficiently low to have minimal potential for bias; and d) relevant baseline characteristics are substantially equivalent among treatment groups.
Class II. Evidence provided by a prospective matched group cohort study in a representative population with masked outcome assessment that meets a through d above or a randomized, controlled clinical trial that lacks one criterion a through d.
Class III. All other controlled trials (including well-defined natural history controls or patients serving as their own controls) in a representative population where outcome assessment is independent of patient treatment.
Class IV. Evidence from studies not assessing outcomes independent of treatment, uncontrolled studies, case series, case reports, or expert opinion.
