Ocular versus cervical VEMPs in the diagnosis of superior semicircular canal dehiscence syndrome

OBJECTIVES: To determine whether cervical vestibular evoked myogenic potential (cVEMP) thresholds or ocular VEMP (oVEMP) amplitudes are more sensitive and specific in the diagnosis of superior semicircular canal dehiscence syndrome (SCDS). STUDY DESIGN: Prospective case-control study. SETTING: Tertiary referral center. SUBJECTS AND METHODS: Twenty-nine patients with SCDS (mean age 48 yr; range, 31-66 yr) and 25 age-matched controls (mean age 48 yr; range, 30-66 yr). INTERVENTION(S): cVEMP and oVEMP in response to air-conducted sound. All patients underwent surgery for repair of SCDS. MAIN OUTCOME MEASURE(S): cVEMP thresholds; oVEMP n10 and peak-to-peak amplitudes. RESULTS: cVEMP threshold results showed sensitivity and specificity ranging from 80% to 100% for the diagnosis of SCDS. In contrast, oVEMP amplitudes demonstrated sensitivity and specificity greater than 90%. CONCLUSION: oVEMP amplitudes are superior to cVEMP thresholds in the diagnosis of SCDS.