A Case of Image-Guided Posterior Tympanotomy in Chronic Otitis Media / 대한이비인후과학회지

Posterior tympanotomy is a procedure performed to access the posterior mesotympanum through a mastoid exposure while preserving the posterior external auditory canal wall. It is dangereous to drill the the site of procedure, as it is surrounded by incuidal fossa superiorly, facial nerve posteriomedially, and chorda tympani nerve anterolaterally, and forms a very narrow pathway. There is always a risk of surgical trauma involving important surgical structures, especially facial nerve and chorda tympani nerve. The development of image-guided surgery (IGS) has significantly improved the performance of many surgical procedures by aiding the identification of surgical landmarks, improving surgical outcomes, rendering the procedure safer and more efficient, especially for beginner otologic surgery, in revision operations, in cases of massive bleeding and tumor of complex anatomy. To see how IGS could help otologic surgeons to identify fine, important structures during posterior tympanotomy, we report a case of posterior tympanotomy in chronic otitis media, which was done using the image-guided surgical technique.

A Spatial Index Analysis for Decision on the First Opening of Facial Recess in Posterior Tympanotomy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Temporal bone is a complicated structure anatomically. Highresolution computed tomography (HRCT) provides a good method for examination of the middle ear, inner ear anatomy and pathologic changes in the temporal bones. The purpose of this study is to evaluate the relations of facial nerve and other structures in temporal bone and factors influencing access to posterior tympanotomy according to the age, sex and degree of temporal bone pneumatizaton. SUBJECTS AND METHOD: A total of 133 ears of temporal bone computer tomograph (TBCT) were analyzed. We measured the distances and angle between important surgical landmarks, and compared the data according to the age, sex and mastoid pneumatization. RESULTS: We presented the angle between the posterior wall of external auditory canal and the facial nerve with the index for facial nerve preservation in posterior tympanotomy. This angle is 10.05 degrees other indices are not related statistically. CONCLUSION: This results may enable preoperative assessment and provide background knowledge to prevent facial nerve injury when performing a posterior tympanotomy.