[Contribution of the vestibular evoked myogenic potentials to the study of the vestibular neuritis].

INTRODUCTION

Until recently, the only tests available to provide information about vestibular function were caloric and kinetic tests, which only give us information about the external semicircular canal and the superior vestibular nerve. In recent years the development of vestibular evoked myogenic potentials has allowed us to assess the saccule and the inferior vestibular nerve. Our aim is, by studying the caloric test results as well as the vestibular evoked myogenic potentials in patients with Vestibular Neuritis, to determine whether they have involvement of the superior, inferior or both vestibular nerves.

MATERIAL AND METHODS

Retrospective study of 9 patients with Vestibular Neuritis admitted to a tertiary care hospital. We studied them by means of anamnesis, otoneurological clinical examination, caloric test and vestibular evoked myogenic potentials. Their clinical progress after admission and any residual instability were also studied.

RESULTS

Women were more affected (66.6 %) than males. The mean age for presentation of the disease was 53.8 +/- 14.0 years. Hospital stays lasted for 5.7 +/- 3.2 days. After their crises, they suffered from instability for 122 +/- 114 days. Four cases were diagnosed as Complete Vestibular Neuritis and five as Superior Vestibular Neuritis. P13 wave latency was normal in all cases. There were no differences between the groups in terms of the length of hospital stay nor residual instability.

CONCLUSIONS

Nowadays, vestibular evoked myogenic potentials make it possible to advance further in the study of Vestibular Neuritis. Complete and superior vestibular neuritis are much more frequent than inferior vestibular neuritis. Clinical behaviour is similar in the sub-types found.