AUDITORY BRAINSTEM FUNCTION IN WOMEN WITH VESTIBULAR MIGRAINE: A CONTROLLED STUDY

Abstract

Introduction The link between vestibular symptoms and migraine led to the publication of diagnostic criteria of a new disorder named vestibular migraine (1,2,3). Even though there is a high frequency of auditory symptoms associated with migraine, there is not enough information on how it occurs. The psychoacoustic evaluation is normal in most cases, although hearing loss is reported in acute migraine and vestibular migraine situations, probably as results of cochlear vasospasms (3-8). Specific auditory symptoms such as phonophobia, hearing loss and tinnitus suggest impairment of auditory pathways in migraine cases (2). Auditory brainstem responses can be assessed by electrophysiological exams. Furthermore, brainstem electric disorders could also affect the stapedius muscle reflex or the acoustic reflex due to dysfunctions in higher auditory centers areas or supratentorial structures (9,10). Objective The aim of this study is to assess auditory brainstem auditory function in women with vestibular migraine by means of electrophysiological testing and acoustic reflex threshold and to verify the presence of hyperacusis in vestibular migraine population, according to loudness discomfort level as defined by to Nields et al. (11). Materials and Methods This case-control study enrolled 29 women with vestibular migraine according to the criteria of Neuhauser et al. modified by the Barany Society and International Headache Society (2) in the study group, during their interictal period. The control group was comprised by 25 healthy women matched to the study group according to their age. The subjects in the study group were recruited from the vestibular migraine outpatient clinic at the Neurotology service. The control group subjects were volunteers. The following tests were performed in both groups Auditory brainstem response Auditory brainstem response suppression Frequency following response Loudness discomfort level assessment Contralateral acoustic reflex assessment Binaural interaction component A descriptive analysis of the data taking into consideration absolute and relative frequencies, central tendency measures and dispersion measures was performed. For quantitative variables, the standard distribution was verified, and the t-Student test used to compare both groups. The equality of variance was not assumed when homogeneity could not be confirmed within a certain variable. In the association analyses between independent qualitative variables and the outcome measures, the Qui-square test was used. For statistical significance, a descriptive level of 5% (p 0.05). The frequency following response latency of the study group showed average values significantly higher to those for the control group in both ears (p 0.05). Conclusion The current study suggested that the temporal auditory processing as well as the loudness discomfort level are altered in VM patients during the interictal period and may be used as diagnostic criteria III. Topico 16 Migranas incluyendo migrana vestibular