Temporal bone dissection skill: A necessity for life otologic surgeries?

Abstract

Background: The anatomy of the temporal bone is complex and not easily learned. Hours of study in the temporal bone laboratory are required for a good grasp by the intending otologic surgeon in order to avoid predictable complications. Aim and Objective: This study aims at highlighting the steps involved toward acquiring the necessary skills and understanding this complex anatomy before embarking on life otological surgeries (temporal bones surgeries and cochlear implant) in our center. Materials and Methods: This was a prospective study of cadaver temporal bone dissection conducted over a period of 3 months. A total of 10 dry, formalin-fixed cadavers were used for the dissection. A team of doctors headed by a consultant otolaryngologist carried out the dissections on the cadavers. The landmark of importance for the dissections was the McEwen's triangle. From this starting point, various otologic surgeries were performed hands-on on the cadavers using the appropriate burs and their sizes. Anatomic features encountered during the dissection were noted and recorded. Results: The 10 cadavers (100%) were all adult males. The youngest and oldest cadavers were aged 25 and 45 years, respectively, with an overall mean age of 38.9 years. The interval between death and embalmment varied from 5 to 79 days. The suprameatal crest, dural plate, aditus and antrum were all present in the 20 temporal bones dissected. Cribrifossae and wide marrow mastoid cavity were noted in 17 (85%) temporal bones each, highly pneumatized mastoid, herald air cells and incus were seen in 14 (70%) each, tympanic remnant was seen in 13 (65%) and stapes in 6 (30%). Conclusion: Temporal bone dissection provides an avenue in understanding the anatomic features and the variations that may pose a challenge in cochlear implant and other otologic surgeries and it enhances the dexterity of the otologic surgeon.