Definitions of the levels of the recommendations (A, B, C, U) and classification of the evidence (Class I through Class IV) are provided at the end of the "Major Recommendations" field.
- What maneuvers effectively treat posterior canal benign paroxysmal positional vertigo (BPPV)?
Conclusion
Two Class I studies and three Class II studies have demonstrated a short-term (1 day to 4 weeks) resolution of symptoms in patients treated with the canalith repositioning procedure (CRP), with number needed to treat (NNT) ranging from 1.43 to 3.7. The Semont maneuver is possibly more effective than no treatment (Class III), a sham treatment (Class II), or Brandt–Daroff exercises (Class IV) as treatment for posterior canal BPPV. Two Class IV studies comparing CRP with Semont maneuver have produced conflicting results; one showed no difference between groups, and the other showed a lower recurrence rate in patients undergoing CRP.
Recommendation
CRP is established as an effective and safe therapy that should be offered to patients of all ages with posterior semicircular canal BPPV (Level A recommendation). The Semont maneuver is possibly effective for BPPV but receives only a Level C recommendation based on a single Class II study. Although many experts believe that the Semont maneuver is as effective as canalith repositioning maneuver, based on currently published articles the Semont maneuver can only be classified as "possibly effective." There is insufficient evidence to establish the relative efficacy of the Semont maneuver to CRP (Level U).
- Which maneuvers are the most effective treatments for horizontal canal and anterior canal BPPV?
Conclusion
Based on Class IV studies, variations of the Lempert supine roll maneuver, the Gufoni method, or forced prolonged positioning seem moderately effective for horizontal canal BPPV. Two uncontrolled Class IV studies report high response rates to maneuvers for anterior canal BPPV.
Recommendation
None (Level U)
- Are postmaneuver activity restrictions necessary after canalith repositioning procedure?
Conclusion and Recommendation
Five Class IV studies support the omission of post-treatment activity restrictions; one study supports the use of post-treatment restrictions. There is insufficient evidence to determine the efficacy of postmaneuver restrictions in patients treated with CRP (Level U).
- Is it necessary to include mastoid vibration with repositioning maneuvers?
Conclusion and Recommendation
One Class II, one Class III, and two Class IV studies showed no added benefit when mastoid vibration was added to a CRP as treatment for posterior canal BPPV. Mastoid oscillation is probably of no added benefit to patients treated with CRP for posterior canal BPPV (Level C recommendation).
- What is the efficacy of Brandt–Daroff exercises, habituation exercises, or patient self-administered treatments for BPPV?
Conclusion and Recommendation
One Class II and one Class IV study suggest that Brandt–Daroff exercises or habituation exercises are less effective than CRP in the treatment of posterior canal BPPV. Self-administered Brandt–Daroff exercises or habituation exercises are less effective than CRP in the treatment of posterior canal BPPV (Level C). There is insufficient evidence to recommend or refute self-treatment using Semont maneuver or CRP for BPPV (Level U).
- What is the efficacy of medication treatments for BPPV?
Conclusion and Recommendation
A single Class III study did not demonstrate that lorazepam or diazepam hastened resolution of symptoms in BPPV. A single Class III study demonstrated some benefit of flunarizine, a drug that is unavailable in the United States, in BPPV. There is no evidence to support a recommendation of any medication in the routine treatment for BPPV (Level U).
- What are the safety and efficacy of surgical treatments for posterior canal BPPV?
Conclusion and Recommendation
Six unblinded, retrospective Class IV studies report relief from symptoms of BPPV in nearly every patient undergoing posterior semicircular canal occlusion or singular neurectomy. Because the studies are Class IV, they do not provide sufficient evidence to recommend or refute posterior semicircular canal occlusion or singular neurectomy as treatment for BPPV (Level U).
Definitions:
Classification of Evidence for Therapeutic Intervention
Class I: Prospective, randomized, controlled clinical trial with masked outcome assessment, in a representative population. The following are required: (a) primary outcome(s) clearly defined; (b) exclusion/inclusion criteria clearly defined; (c) adequate accounting for drop-outs and cross-overs with numbers sufficiently low to have minimal potential for bias; and (d) relevant baseline characteristics are presented and substantially equivalent among treatment groups or there is appropriate statistical adjustment for differences.
Class II: Prospective matched group cohort study in a representative population with masked outcome assessment that meets a-d above OR a randomized controlled trial in a representative population that lacks one criteria a-d.
Class III: All other controlled trials (including well-defined natural history controls or patients serving as own controls) in a representative population, where outcome is independently assessed, or independently derived by objective outcome measurement.*
Class IV: Evidence from uncontrolled studies, case series, case reports, or expert opinion.
* Objective outcome measurement: an outcome measure that is unlikely to be affected by an observer's (patient, treating physician, investigator) expectation or bias (e.g., blood tests, administrative outcome data).
Classification of Recommendations
Level A = Established as effective, ineffective, or harmful for the given condition in the specified population. (Level A rating requires at least two consistent Class I studies.)
Level B = Probably effective, ineffective, or harmful for the given condition in the specified population. (Level B rating requires at least one Class I study or at least two consistent Class II studies.)
Level C = Possibly effective, ineffective, or harmful for the given condition in the specified population. (Level C rating requires at least one Class II study or at least two consistent Class III studies.)
Level U = Data inadequate or conflicting; given current knowledge, treatment is unproven.