Menière's disease - roentgenologic diagnosis.

Radiologic diagnosis in Menière's disease should not be based on the vestibular aqueducts tomographic reproducibility. Instead, valuable preoperative information should be given about the size and location of the aqueducts external aperture in relation to the posterior and lateral semicircular canals. In saccotomy the semicircular canals are landmarks for identification of the endolymphatic sac. The periaqueductal pneumatization is demonstrated to be partly decisive for the vestibular aqueducts gross morphology. In Menière's disease either a sparse or a total lack of periaqueductal pneumatization is observed in most of all cases. The development of peri- and infralabyrinthine pneumatization is also decisive for the position of the foveate impression, which houses the extraosseous part of the endolymphatic sac. Its location and size can be evaluated by tomographic characterization of the vestibular aqueducts external aperture.