Abstract
Thirty-two patients with idiopathic unilateral auditory and/or vestibular symptoms (19 females and 13 males, mean age of 62.2 years) were evaluated with T2—weighted MR images (MRI). MRI of 18 patients with sudden deafness or vestibular neuronitis (10 females and 8 males, mean age of 54.9 years) were used as controls. Displacement of the basilar artery from the midline were assessed at the level of the internal auditory meatus in the axial view. The displacement was ipsilateral to the symptoms in 26 (81.3%) and contralateral in 6 (18.7%) of 32 patients, whereas it was ipsilateral to the lesion in 4 (22.2%), contralateral in 7 (38.9%) and not recognized in 7 (38.9%) of 18 control patients. Statistical analysis revealed that the patients with idiopathic unilateral auditory and/or vestibular symptoms had ipsilateral displacement of the basilar artery at a significantly high incidence, which may have developed as a result of ipsilateral dolichoectasia due to sclerotic change of the vertebrobasilar artery, leading to a unilateral lesion such as neurovascular compression or chronic blood flow change of the 8th cranial nerve or inner ear.
