RETROSPECTIVE ANALYSIS OF THE COMPATIBILITY OF INTRAOPERATIVE FINDINGS WITH PREOPERATIVE HIGH RESOLUTION TEMPORAL BONE COMPUTED TOMOGRAPHY IN CHRONIC SUPPURATIVE OTITIS MEDIA
1Ordu Üniversitesi Tıp Fakültesi, KBB Anabilim Dalı, Ordu, Türkiye2Ankara Şehir Hastanesi, KBB Hastalıkları Kliniği, Ankara, Türkiye
3Yıldırım Beyazıt Üniversitesi Tıp Fakültesi, KBB Anabilim Dalı, Ankara, Türkiye Objective: This study compared the preoperative findings of high resolution temporal bone computed tomography (HRCT) with otoscopic-microscopic examination in chronic suppurative otitis media (CSOM) cases which are not complicated with intracranial or extracranial complications.
Patients and Method: Adult 82 CSOM cases, without any history of otologic surgery, operated on canal wall up (CWU) or canal wall down (CWD) tympanomastoidectomy were analysed retrospectively. Preoperative HRCT findings were compared with intraoperative findings. The matching of findings (true positive, false positive, true negative, false negative, sensitivity, specificity, positive predictive value and negative predictive value) was analysed to understand which of the findings is most compatible.
Results: HRCT was found to have high sensitivity for diagnosis of cholesteatoma (85.2%), ossicular chain discontinuity (80.4%), lateral semisircular canal (LSSC) dehiscence (100%), scutum erosion (85.2%), tegmen tympani erosion and posterior fossa dural plate erosion (100%), however it has a low sensitivity for diagnosis of facial nerve canal dehiscence (52.9%). The specificities of these lesions with HRCT were calculated as 100%, 100%, 97.5%, 100%, 96.1% and 100%; respectively.
Conclusion: HRCT alone was found to be insufficent in diagnosis of facial nerve canal dehiscence. However, HRCT is still an indispensable imaging modality to plan for accurate surgical technique -including additional procedures as ossicular chain reconstruction and bony defect repair- and to minimize intraoperative complications.
Keywords : Temporal Bone, High-Resolution Computed Tomography (HRCT), Chronic Otitis Media, Mastoidectomy, Facial Nerve