Vestibular-evoked myogenic potentials in patients with severe obstructive sleep apnea

OBJECTIVE: Previous studies have shown that patients with obstructive sleep apnea syndrome (OSAS) may have various vestibular abnormalities, and these mainly present as subclinical lesions. In this study, we attempted to combine ocular vestibular-evoked myogenic potentials (VEMPs) and cervical (VEMPs) to investigate vestibular dysfunction in patients with OSAS. METHODS: Thirty-eight patients with severe OSAS and 42 healthy controls were enrolled and divided into two groups according to results of polysomnography. All parameters of VEMP graphs were analyzed. RESULTS: The response rate of ocular VEMPs was significantly lower in patients with severe OSAS (85.5%) than in controls (96.4%). The mean n1 latency of patients with severe OSAS (10.6 ± 1.0 months) was significantly longer than that of controls (10.2 ± 1.1 months). With regard to cervical VEMP, p1-n1 amplitudes were significantly different between the groups. Other VEMP parameters were not significantly different between the groups. CONCLUSIONS: VEMPs can potentially be used to evaluate vestibular system lesions at the early stage of OSAS, including not only the vestibular nerve, but also the otolith organs involved.