Auditory brainstem function in women with vestibular migraine: a controlled study

DOI: https://doi.org/10.1186/s12883- 019- 1368- 5

Abstract-Summary The aim of this study was to assess auditory brainstem function in women with vestibular migraine using electrophysiological testing, contralateral acoustic reflex and loudness discomfort level.

The study group consisted of 29 women with vestibular migraine in the interictal

period, and the control group comprised 25 healthy women.

The threshold of loudness discomfort and the contralateral acoustic reflex were

also investigated.

There was a statistically significant difference between the groups in the fre-

quency following response and the loudness discomfort level.

The current study suggested that temporal auditory processing and loudness dis- comfort levels are altered in VM patients during the interictal period, indicating that these measures may be useful as diagnostic criteria.

Extended: The aim of this study is to assess auditory brainstem function in women with vestibular migraine by means of electrophysiological testing and acoustic reflex thresholds and to verify the presence of hyperacusis according to loudness discomfort level, as defined by Nields and others [278].

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2 Mechanisms

There was a statistically significant difference in the average loudness discom- fort level threshold of the right ear between the groups at 250 Hz (p = 0.006), 500 Hz (p = 0.013) and 3000 Hz (p = 0.023).

The current study suggested that temporal auditory processing and the loudness discomfort level are altered in vestibular migraine patients during the interictal period and may be used as diagnostic criteria.

Background Although there is a high frequency of auditory symptoms associated with migraine, there is inadequate information regarding how migraine occurs; vestibular assess- ments performed via hearing tests do not provide enough specific data.

Specific auditory symptoms such as phonophobia (vestibular migraine and migraine without aura diagnosis criteria) and hearing loss and tinnitus (brainstem migraine with aura diagnosis criteria) suggest impairment of auditory pathways in migraine cases [279].

The aim of this study is to assess auditory brainstem function in women with vestibular migraine by means of electrophysiological testing and acoustic reflex thresholds and to verify the presence of hyperacusis according to loudness discom- fort level, as defined by Nields and others [278].

Methods The response cycles obtained for the study group were compared to those obtained for the control group.

Waveforms were obtained at 70 dBHL in the following order: (a) Right ear response without contralateral noise; (b) Right ear response with contralateral noise; (c) Left ear response without contralateral noise; (d) Left ear response with contra- lateral noise; The absolute latencies for waves I, III and V and the interpeak I-III, III-V and I-V latencies without noise were subtracted from the results with contra- lateral noise, and the results were compared between the groups.

Contralateral acoustic reflex testing was performed at 500, 1000, 2000 and 4000 Hz for each ear in both groups using AT235 Interacoustics® equipment, with pure tone presentations lasting 1.5 s. Each stimulus was presented for 1.5 s at an initial intensity of 70 dBHL and was increased by 5-dBHL steps until the acoustic reflex was obtained.

Results There was no statistically significant difference between the average latency and amplitude of binaural interaction component values when the study group and the control group were compared.

The frequency following response latencies of the study group had average val- ues that were significantly higher than those of the control group in both ears (p < 0.05), except for the latency of wave I in the left ear (p = 0.102).

The frequency following response interpeak I-III variable in the left ear differed

significantly between the groups (p = 0.003).

There was a statistically significant difference in the average loudness discom- fort level threshold of the right ear between the groups at 250 Hz (p = 0.006), 500 Hz (p = 0.013) and 3000 Hz (p = 0.023).

2.2 Biology

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Discussion The frequency following response latencies were significantly longer in the patients with vestibular migraine than in the control group, suggesting altered pure tone temporal processing, which may also affect the processing of complex sounds.

The remaining electrophysiologic tests did not show any significant difference, suggesting that binaural hearing, efferent auditory brainstem response suppression and auditory brainstem response are not altered in patients with vestibular migraine during the interictal period.

Auditory brainstem response suppression with contralateral white noise in ves- tibular migraine did not yield any significant differences between the study group and the control group.

As previous studies have suggested [280–282], there were no differences in audi- tory brainstem click responses between groups during the migraine interictal period. The auditory temporal processing brainstem disorder evidenced by the frequency following response and the mild hyperacusis observed in this study reinforce the hypothesis that the inferior colliculus has an important role in migraine and vestibu- lar migraine pathophysiology.

Acknowledgement A machine generated summary based on the work of Takeuti, Alice A.; Fávero, Mariana L.; Zaia, Erica Helena; Ganança, Fernando F. 2019 in BMC Neurology.

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