Practice guideline: Cervical and ocular vestibular evoked myogenic potential testing

Abstract

Objective: To systematically review the evidence and make recommendations with regard to diagnostic utility of cervical and ocular vestibular evoked myogenic potentials (cVEMP and oVEMP, respectively). Four questions were asked: Does cVEMP accurately identify superior canal dehis-cence syndrome (SCDS)? Does oVEMP accurately identify SCDS? For suspected vestibular symptoms, does cVEMP/oVEMP accurately identify vestibular dysfunction related to the sac-cule/utricle? For vestibular symptoms, does cVEMP/oVEMP accurately and substantively aid diagnosis of any specific vestibular disorder besides SCDS? Methods: The guideline panel identified and classified relevant published studies (January 1980-December 2016) according to the 2004 American Academy of Neurology process. Results and Recommendations: Level C positive: Clinicians may use cVEMP stimulus threshold values to distinguish SCDS from controls (2 Class III studies) (sensitivity 86%-91%, specificity 90%-96%). Corrected cVEMP amplitude may be used to distinguish SCDS from controls (2 Class III studies) (sensitivity 100%, specificity 93%). Clinicians may use oVEMP amplitude to distinguish SCDS from normal controls (3 Class III studies) (sensitivity 77%-100%, specificity 98%-100%). oVEMP threshold may be used to aid in distinguishing SCDS from controls (3 Class III studies) (sensitivity 70%-100%, specificity 77%-100%). Level U: Evidence is insufficient to determine whether cVEMP and oVEMP can accurately identify vestibular function specifically related to the saccule/utricle, or whether cVEMP or oVEMP is useful in diagnosing vestibular neuritis or Ménière disease. Level C negative: It has not been demonstrated that cVEMP substantively aids in diagnosing benign paroxysmal positional vertigo, or that cVEMP or oVEMP aids in diagnosing/managing vestibular migraine. Neurology ® 2017;89:2288-2296 GLOSSARY AAN 5 American Academy of Neurology; BPPV 5 benign paroxysmal positional vertigo; CI 5 confidence interval; cVEMP 5 cervical vestibular evoked myogenic potential; nHL 5 normal hearing level; oVEMP 5 ocular vestibular evoked myogenic potential; SCDS 5 superior canal dehiscence syndrome; VEMP 5 vestibular evoked myogenic potential; VM 5 vestibular migraine; VN 5 vestibular neuritis. Vestibular evoked myogenic potential (VEMP) testing averages short latency myogenic responses evoked by sound that stimulates activation of the saccule or utricle, or both. 1,2 The US Food and Drug Administration approved VEMP in October 2015. Caloric testing assesses only horizontal semicircular canal vestibulo-ocular reflex function, and the video head impulse test assesses function of all 6 semicircular canals, whereas VEMP testing appears to assess function of only the saccule/utricle. 3-6 Types of VEMP testing. There are 2 types of VEMP testing: cervical VEMP (cVEMP) and ocular VEMP (oVEMP). The cVEMP test is believed to assess saccular ves-tibular signals carried via the vestibulospinal tract. 7 cVEMP is performed by applying sound stimulation to 1 ear while recording surface EMG over the ipsi-lateral sternocleidomastoid muscle (figure 1). Sound-responsive vestibular cells, mainly within the inner ear saccule, momentarily inhibit ipsilateral muscle tone