[MR imaging of the inner ear; findings of Ménière's syndrome].

Symptoms in Ménière's disease are explained by hydrops of endolymphatic system with recurrent ruptures of the membranous labyrinth. The primary cause of the increased endolymphatic volume appears to be an imbalance between secretion and resorption of endolymph which may be due to an obstruction of the endolymphatic duct and sac, located in the vestibular aqueduct. Non-visualization or narrowing of the vestibular aqueduct of the paper have been demonstrated by conventional tomography and high resolution computed tomography (HR-CT). But the endolymphatic duct and sac can not be obtained by HR-CT and conventional tomography. Whereas, on MRI, these are identified. By MRI, we prospectively tried to demonstrate morphological alterations in 10 patients with Ménière's disease and in 4 patients with vestibular neuronitis. These were compared with a group of 20 normal men. Visualization of the endolymphatic duct and sac (vestibular aqueduct) on MRI was assessed. There was a distinctly decreased visualization of the vestibular aqueduct in the Ménière group and vestibular neuronitis group. We were able to confirm a statistically proven usefulness of the MRI technique in identifying an anatomical abnormality which is directly in correlation with the side of the lesion in cases of unilateral Ménière's disease.