The Clinical Study Of Migraineurs' Hearing And The Function Of Brainstem

Objectives:(1)Pure tone hearing threshold is a common investigation for evaluating hearing sensitivity. We studied migraineurs' pure tone hearing threshold changes and the possible reasons.(2)Brainstem is an important structure in migraine. Comparing to regular investigation of auditory brainstem response, investigation of auditory brainstem response with increasing stimulus rate may be more sensitive to brainstem abnormalities. We investigated migraineurs' auditory brainstem response with increasing stimulus rate to evaluate their function of brainstem.Material and method:(1)58 migraineurs in pain-free interval and 46 age-matched healthy controls were recruited in this study. They were all examined with pure tone hearing threshold investigation. The frequecies were 250HZ, 500HZ, 1000HZ, 2000HZ, 4000Hz and 8000HZ. Migraineurs' pure tone hearing threshold were compared to that of healthy controls by t test, t' test or nonparametric test. Migraineurs were divided into migraineurs without aura and migraineurs with aura. The results of the two groups were compared to study the differences of the hearing threshold between migraine with aura and without aura.(2)55 migraineurs in pain-free interval and 42 age-matched healthy controls were recruited in this study. They were all examined with investigation of auditory brainstem response with increasing stimulus rate. The click rate were 11.1/s and 51.1/s. The I ,III, V peak latencies and I -III,III-V, I -V inter peak latencies in these two groups were compared by t test, t' test or nonparametric test.Results:(1)The pure tone hearing threshold is higher in migraineurs than healthy controls at all frequencies.(2)There was significant difference between migraineurs' I , III, V peak latencies and I-III,III-V,I-V inter peak latencies and those of healthy controlswith click rate at 11.1/s. The I -III inter peak latencies were longer at left side in migraineurs than healthy controls' with click rate at 51.1 /s. The diffrences of other peak latencies or inter peak latencies between the two groups were not significant. The difference of I -V inter peak latencies between high and low click rates in migraineurs was larger than that of healthy controls.Conclusions:(1) Migraineurs' hearing may be impaired. The hearing sensitivity of migraineurs without aura may be the same as that of migraineurs with aura.(2)During pain-free interval, the brainstem function of migraineurs were abnormal and asymmetry. Investigation of auditory brainstem response with increasing stimulus rate may be more sensitive than regular investigation of auditory brainstem response.