측두골 전산화단층촬영의 시상주위 영상으로 본 안면신경 및 하악골 관절과 고실윤과의 관계

Background and Objectives: Canaloplasty has been an essential and additional step in the various middle ear surgical procedures. However, Two anatomical structures, the temporomandibular (TM) joint and the facial nerve limit the widening of bony annulus of tympanic bone anteriorly and posteriorly. The aim of this study was to obtain data on the anatomical relationship of facial nerve and TM joint using parasaggital reformatted images created fom high resolutional axial CT images, at the region of tympanic annulus. Patients and Methods: Parasaggital image of temporal bone CT by 3-dimensional reconstruction software in 30 adults who have no history of otitis media or head trauma was performed. Results: 1 ) Average angle between vertical line of parasaggital view and mid portion of 2nd genu at the virtual center of EAC-101.8°, 2) average angle between vertical line of parasaggital view and mid portion of stylomastoid foramen at the virtual center of EAC-31.9°, 3) average angle between horizontal line of parasaggital view and superior margin of TM Joint ant the virtual center of EAC-18.4°, 4) average angle between horizontal line of parasaggital view and bony margin of anterior epitympanum at the virtual center of EAC-43.0°, 5) average distance from bony portion of EAC to mid portion of 2nd genu-2.7 mm. Conclusion: The reconstructed high-resolution CT for planning canalopalsty can be useful in demonstrating related structure and decreasing the likelihood of surgical mishap and improving results. Canalplasty might be safely performed anterior-superiorly and posterior-inferiorly by being reminded of such anatomical parameters. (J Clinical Otolaryngol 2006;17:212–216)