Vestibular autorotation testing in patients with benign paroxysmal positional vertigo

OBJECTIVES: The current gold standard for diagnosis of benign paroxysmal po sitional vertigo (BPPV) is the Dix-Hallpike maneuver. However, because of f atigability, the Dix-Hallpike is often falsely normal. The objective of thi s study was to evaluate the utility of vestibular autorotation testing in t he diagnosis of BPPV. METHODS: The charts of 210 patients at a tertiary referral center for verti ginous disorders were reviewed. All patients underwent clinical evaluation, Dix-Hallpike testing, audiometry, electronystagmography, and vestibular au torotation testing. The vestibular autorotation results of patients with BP PV were compared with the findings in patients with non-BPPV vestibular dis orders. The sensitivity and specificity of vestibular autorotation testing in diagnosing BPPV were calculated. RESULTS: Ninety-one patients (42.9%) had BPPV, 76 patients (36.2%) had vert igo of uncertain cause, 28 (13.3%) had unilateral vestibular hypofunction, 9 patients (4.3%) had Meniere's disease, and 2 patients (1.0%) had perilymp hatic fistula, Patients with BPPV were 3.32 times more likely to have a nor mal horizontal gain (95% CI = 1.54-7.19), A normal horizontal gain is 85% s ensitive but only 36% specific for BPPV. Patients with BPPV were 1,9 times more likely to have vertical phase lead (95% CI = 0.95-3.93). Patients with BPPV were 2.20 times more likely to have both normal horizontal gain and v ertical phase lead (95% CI = 1.03-4.69) The sensitivity of the combination of normal horizontal gain and vertical phase lead on vestibular autorotatio n testing is 87% specific but only 25% sensitive in the diagnosis of BPPV, CONCLUSION: A normal horizontal gain or vertical phase lead on vestibular a utorotation testing in a vertiginous patient is suggestive of but not exclu sive to a diagnosis of BPPV, The combination of a normal horizontal gain an d vertical phase lead on vestibular autorotation testing is highly suggesti ve of the diagnosis of BPPV. Adjuvant use of these parameters in vestibular autorotation testing may prove to be helpful in the diagnosis of BPPV.