Imaging of cochlear obliteration by CISS-MRI.

High-resolution CT images are often unable to visualize the extent of possi ble cochlear obliteration after meningitis or after temporal bone fracture. The exact estimation of this extent, however, is crucial for cochlear impl ant surgery planning. Thus MR imaging of intralabyrinthine pathology is bec oming an increasingly significant imaging modality. Methods: The clinical r elevance of the CISS (constructive interference in steady state) MR sequenc e is explained using 5 selected cases of different inner ear pathology. Res ults: Two of the examined patients had unsuspicious inner ear signals, wher eas in 3 cases MRI rendered relevant information about partial or total coc hlear obliteration. Conclusions: These clinical examples illustrate how the ideal fluid and tissue contrast of CISS-MRI make this new technique suitab le as a primary tool for evaluating inner ear obliteration before cochlear implant surgery.