USE OF SKULL VIBRATION-INDUCED NYSTAGMUS DURING FOLLOW-UP IN MÉNIÈRE.

Abstract

Ménière's disease (MD) is an idiopathic disorder that affects patients' hearing and the inner ear balance. Intratympanic gentamicin (ITG) is also considered an effective treatment for uncontrolled MD characterized by persistent vertigo attacks despite therapy. The video head impulse test (vHIT) and the skull vibration-induced nystagmus (SVIN) are both validated test to assess the vestibular function. A progressive linear relationship has also been described between the slow-phase velocity (SPV) of SVIN with a skull vibrator at 100 Hz and the gain difference (healthy ear/affected ear) measured in vHIT. The objective of this study was to determine whether the SPV of the SVIN was correlated with the restoration of vestibular function after ITG and, consequently, whether the SVIN can predict the appearance of new vertigo attacks in patients with MD treated with ITG. A prospective longitudinal case-control study was conducted. We recorded several variables after ITG and during the follow-up and statistical analyses were performed. Two groups were compared, those who presented vertigo attacks 6 months after ITG and those who did not. Our sample included 88 patients with definite MD who were treated with ITG. Among the 18 patients who experienced vertigo attacks again, 15 showed recovery of the gain of the affected ear, while all 18 showed a reduction in the SPV of the SVIN. SPV of SVIN may have more sensitivity than vHIT for detecting recovery of vestibular function after intratympanic gentamicin (ITG) administration. To the best of our knowledge, this is the first study to describe the association between decreased SPV and the probability of vertigo attacks in patients with MD treated with ITG.