Clinical and Prognostic Implications of Cervical and Ocular Vestibular Evoked Myogenic Potentials (cVEMP and oVEMP) in Benign Paroxysmal Positional Vertigo (BPPV): A Prospective Study.

OBJECTIVE: Several studies have investigated the efficacy of VEMP (vestibular evoked myogenic potential) in patients with vestibular disorders and BPPV (benign paroxysmal positional vertigo). However, previous data were inconclusive. The aim of this study was to investigate the difference in latency, amplitude P1-N1, asymmetry ratio (AR), and cervical/ocular-VEMP values between BPPV patients and healthy controls.

METHODS: 125 healthy subjects and 42 BPPV patients were prospectively enrolled in the study. In both groups, c/oVEMP tests with 500 Hz tone-burst stimuli were performed. Latencies P1, N1 peaks, and corrected amplitudes (CA) were measured, and AR was calculated.

RESULTS: in the BPPV group, 14.29% of patients lacked oVEMPs that recovered after therapy. N1 latencies were significantly elongated, and 50% of patients had pathological AR; this value normalized at follow-up sessions. In addition, there was a reduction in CA in the pathologic ear compared to healthy ears ( p = 0.04) and compared to healthy controls ( p = 0.01). For cVEMP, a significant reduction in latency-P1 was observed in BPPV patients compared to controls; no significant differences were observed for P1, N1, and CA values between the two ears. The cVEMPs were absent in 14.29% of BPPV patients (AR > 35) that recovered after therapy.

CONCLUSION: We identified several abnormal c/oVemp values in BPPV patients compared with healthy controls, with most changes in values occurring in oVEMPs, suggesting that utricular dysfunction may be more common than saccular. In addition, patients with oVEMP alteration showed later clinical recovery, suggesting a possible prognostic role of the test.