الفهرس 
Anatomy and physiology of the inner earOnly 14 pages are availabe for public view
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Abstract
Melanin may have a role in the vasomotor function in the inner ear (4; 8).
Hearing loss in patients with vitiligo is referred to the loss of inner ear melanocytes which play a role in keeping the normal function of the stria vascularis and the cochlea. Moreover, melanocytes are effective in development of endocochlear potentials and preservation of the gradient of ion and fluid between the endolymph and perilymph.
Few previous reports investigated the vestibular function of the ear in patients with vitiligo.
So, this study was conducted to evaluate the auditory and vestibular function in patients with vitiligo. This study included 63 patients with vitiligo with exclusion of patients suffering from medical or neurological problems known to affect audiovestibular system, abnormal middle ear function, cervical spine problems, ototoxic drug intake and noise exposure in addition to 63 healthy individuals not complaining of dizziness as a control group.
All subjects in the study group were subjected to the following: full history taking (Duration of appearance of vitilgo, site, audiovestibular symptoms (HL, tinnitus & vertigo), neurological examination, otoscopic examination, basic audiological assessment (Pure tone audiometry and Immittancemetry) and vestibular assessment in the form of cervical Vestibular evoked myogenic potential (cVEMP) and videonystagmography (VNG).
Our results showed higher prevalence of female gender in cases with vitiligo (60.3%).
Regarding the hearing function: both ears showed significantly higher (worse) hearing threshold compared to controls. The included vitiligo cases with hearing loss (12 cases – 19%).
cVEMP results: cVEMP showed a highly significant differences between cases and controls. VEMPs abnormalities were cases with delayed latency (27 cases – 42.9%), unilateral abcent wave (4cases -6.3%) and bilateral abcent wave 2 cases -3.2%).
VNG results: VNG results revealed that 12 patients with vitiligo had canal weakness, Moreover, 8 patients showed spontaneous nystagmus. 4 patients had abnormal saccadic testing, and 4 patients had abnormal smooth pursuit and 2 patients had benign paroxysmal positional vertigo.
We found that there was statistically significant correlation between head affection of vitiligo and PTA findings .There was no a significant difference between type of vitiligo (segmental-non segmental), and audiovestibular functions except caloric tests that revealed a significant differencewe also found significantly different between disease duration and the audio-vestibular findings.
Mahdi el al. (78) explained that melanocytes take part in vestibular metabolism through an apparent relationship between the dark cells and adjacent blood vessels and in response to various stressful conditions, these cells have been reported to show increased melanin synthesis.