Computed tomographic findings around the vestibular aqueduct in Menière's disease.

High resolution transverse axial CT encompassing the lateral semicircular canal was used to study the visualization of the vestibular aqueduct and to measure the minimum distance between the posterior semicircular canal and the posterior petrous surface (P-P distance) in Meniere's disease and chronic otitis media. The results indicate that the development of the bone between the posterior semicircular canal and the posterior petrous surface, which usually contains the endolymphatic sac, is significantly poorer in affected ears than in nonaffected ears in unilateral Meniere's disease, and much poorer than in chronic otitis media.