Practice Parameter: Therapies for benign paroxysmal positional vertigo (an evidence-based review): [RETIRED]

Abstract

Benign paroxysmal positional vertigo (BPPV) is a clinical syndrome character- ized by brief recurrent episodes of vertigo trig- gered by changes in head position with respect to gravity. BPPV is the most common cause of recur- rent vertigo, with a lifetime prevalence of 2.4%.1 The term BPPV excludes vertigo caused by le- sions of the CNS. BPPV results from abnormal stimulation of the cupula within any of the three semicircular canals (figure e-1 on the Neurology® Web site at www.neurology.org); most cases of BPPV affect the posterior canal. The cupular exci- tatory response is usually related to movement of otoliths (calcium carbonate crystals) that create a current of endolymph within the affected semicir- cular canal. The most common form of BPPV oc- curs when otoliths from the macula of the utricle fall into the lumen of the posterior semicircular canal responding to the effect of gravity. These ectopic otoliths, which have been observed intraoperatively, are referred to as canaliths.Thecanalithsaredense and move in the semicircular canal when the head position is changed with respect to gravity; the cana- lith movement ultimately deflects the cupula, lead- ing to a burst of vertigo and nystagmus. In some cases, canaliths adhere to the cupula, causing cupu- lolithiasis, which is a form of BPPV less responsive to treatment maneuvers. Typical signs of BPPV are evoked when the head is positioned so that the plane of the affected semicircular canal is spatially vertical and thus aligned with gravity. This produces a paroxysm of vertigo and nystagmus after a brief latency. Po- sitioning the head in the opposite direction re- verses the direction of the nystagmus. These responses often fatigue upon repeat positioning. The duration, frequency, and intensity of symptoms of BPPV vary, and spontaneous recovery occurs fre- quently. Table e-1 outlines the characteristics of BPPV by canal type. Repositioning maneuvers are believed to treat BPPV by moving the canaliths from the semicir- cular canal to the vestibule from which they are absorbed. There are a number of repositioning maneuvers in use, but they lack standardization. The figures and Web-based video clips do not in- clude all variations but represent those maneuvers and treatments used in the Class I and Class II studies that are reviewed as well as several others in common use. This practice parameter seeks to answer the fol- lowing questions: 1) What maneuvers effectively treat posterior canal BPPV? 2) Which maneuvers are effective for anterior and horizontal canal BPPV? 3) Are postmaneuver restrictions necessary? 4) Is con- current mastoid vibration important for efficacy of the maneuvers? 5) What is the efficacy of habitua- tion exercises, Brandt–Daroff exercises, or patient self-administered treatment maneuvers? 6) Are med- ications effective for BPPV? 7) Is surgical occlusion of the posterior canal or singular neurectomy effec- tive for BPPV?