3D Imaging of the Membranous Labyrinth: Normal Anatomy and Pathological Conditions

Objective The standard for studying temporal bone anatomy has been histopathological sectioning for microtome following chemical fixation and deossification of the temporal bone specimen. We can directly synthesize the membranous labyrinth from the conventional CT exam. We evaluated normal anatomy and pathological conditions of the membranous labyrinth. Method We studied 20 normal subjects, 20 hyperlipidemias, 20 DMs, 4 Ménière diseases, and 2 congenital malformations. To develop a 3D reconstructed image of the membranous labyrinth based on HR‐CT, the axial data were applied to create 3D images on the CT work station for postprocessing with factory presets. Results 3D visualization of different structures of the membranous labyrinth allowed display of correct anatomy of high detail in all normal subjects. We could observe the cochlear duct, ductus reuniens, saccule, utricle, and ampullae. Otherwise, pathological conditions were revealed as irregular shape of the cochlear duct and/or small or large saccule or utericle. On unilateral Ménière disease, we could find the enlargement of the utricle. The radiation exposure was 0.15mSv. Conclusion Our method shows promise for observation of the membranous labyrinth. The pathological conditional images showed abnormal shape in comparison with normal conditions. We got a new diagnostic method for vertigo, disequilibrium, hearing loss, and tinnitus.