High-resolution Computed Tomography(HRCT)of nthe telnporal bone has now becolne a routine test for the diagnosis of various temporal bone lesions.Correct assessment of such minute structures as ossicles, especially stapes, is important in the pre-operative HRCT evaluation.On the other hand, analysis for the reliability of HRCT findings has not been done, including the superstructure of the stapes.
A retrospectively study was done in oder to assess the availability of HRCT findings in axial overlapping scans in 226 ears, with respect to the superstructures of stapes.The study was concerned with the analysis of HRCTs of 148 normal ears, 71 ears of chronic otitis media and7ears of ossicular abnormalities.HRCT findings were compared to those of surgeries in pathological cases.
The present study revealed that the superstructures of stapes are noted in 70% when the stapes surrounded by air.The major limitations in the proper analysis of stapes by HRCT are partial volume averaging and effects of soft tissue silhouetting, this is especially so when the stapes is surrounded by soft tissue density.