Prevalence of Carotid Canal Dehiscence Facing with Middle Ear and its Relationship with Tinnitus

Aim: To assess the frequency of carotid canal dehiscence facing with middle ear cleft and its relationship with pulsatile tinnitus. Material and Method: High resolution computed tomography scans (reformatted from the axial plane images taken for paranasal sinus investigations) of 1026 temporal bone images of 513 patients were retrospectively examined for the presence of dehiscent internal carotid artery. The presence of pulsatile tinnitus complaint was noted. The relationship between carotid canal dehiscence in the middle ear and pulsatile tinnitus was investigated. Results: One thousand and twenty-six (1,026) temporal bone images of 513 patients were investigated for the presence of carotid canal dehiscence in the middle ear(30.9 %). Three hundred and eighteen (318) out of 1026 temporal bone images proved to present carotid canal dehiscence in the middle ear. There were 16 ears with pulsatile tinnitus at the site of dehiscent carotid canal. There were 19 ears with pulsatile tinnitus at the site of the temporal bone without carotid canal dehiscence. There was no statistically significant correlation between the carotid canal dehiscence and pulsatile tinnitus. Discussion: Neither age nor gender is a determining factor for the presence of carotid canal dehiscence. Pulsatile tinnitus seems not to be related with carotid canal dehiscence