Measurement Study On Tympanoplasty By MDCT3D Reconstruction

Objective:Use the MPR technique of MDCTand the reconstruction of ossicular chain to measure the data of normal ossicular chain. To assess the relationship among tympanic membrane,stape and PORP.Material and Methods:1.33samples of temporal bone without ear disease are scanned by SIEMEMS LightSpeedUltra16rows of spiral CT.2.All patiants were scaned on supine position with collimation and pitch value of1.0and0.75mm, respectively, exposure duration of4.5-5.5s(120kV,180mAsl and a field of view (FOV) of107mm. Images were reconstructed using a bone algoritum reconstruction kernel at0.3-mm interval.The data was transferred to a workstation via all internal Dicom network for post-processing.Results:The oblique reconstruction of stapes and the MPR technique of MDCT rebuild the positions, shapes of the three pieces of ossicular clearly,and the reconstruction of3D view can reveal the spatial relationship between every structure stereoscopically. The angle between the two planes is47.4±12.0°.Conclusions:The angle between PORP and tympanic membrane should be close to45°.