Anatomical Study of the Facial Recess with Implications in Round Window Visibility for Cochlear Implantation: Personal Observations and Review of the Literature

Abstract Introduction Posterior tympanotomy through facial recess (FR) is the conventional and most preferred approach to facilitate cochlear implantation, especially when the electrode is inserted through the round window. The complications of the FR approach can be minimized by proper understanding of the anatomy of the FR. Objective The present study was undertaken to assess the various parameters of FR and round window visibility, which may be of relevance for cochlear implant surgery. Methods Thirty-five normal wet human cadaveric temporal bones were studied by dissection for anatomy of FR and posterior tympanum. Photographs were taken with an 18megapixels digital camera, which were then imported to a computer to determine various parameters. Results The mean distance from the take-off point/crotch of the chorda tympani nerve (CTN) to the stylomastoid foramen was 4.08 ± 0.8 mm(range of 2.06 - 5.5mm). The variations in the course of the CTN included origin at the level of the lateral semicircular canal. Themean chorda-facial angle in our study was 26.91° ± 1.19°, with a range of 25° to 28.69°. The mean FR length ranged between 9.4 mm and 18.56 mm (mean of 12.41 ± 2.91mm) and varied with the origin of the CTN and pneumatization of temporal bone. The average maximum width of the FR was 2.93 ± 0.4 mm (range 2.24-3.45 mm) and the mean width of the FR at the level of the round window was 2.65 ± 0.41 mm. Conclusion The FR approach provides good access to the round windowmembrane in all cases. In some cases, table adjustment is required.

A Type-II First Branchial Cleft Anomaly Presenting as a Post-Auricular Salivary Fistula: A Rare Presentation.

First branchial cleft anomalies are rare with the average age of presentation as 19 years. There is an average delay of 3.5 years between initial presentation and adequate treatment due to diagnostic dilemma. A very rare variant of first branchial cleft anomaly presenting as a post-auricular salivary fistula is reported. A 12-year-old girl presented with a history of intermittent watery discharge, more so at the time of meals from a right post-auricular opening for last 3 years. Computed tomography sialography revealed a fistulous tract connecting the sub segmental duct of the parotid gland extending along the pre-tragus region in subcutaneous plane up to mastoid tip after passing inferior to external auditory canal. Superficial parotidectomy with identification of facial nerve branches was carried out for excision of the tract. Histopathology revealed sinus tract comprising of ectodermal components and acini of the parotid gland. We classified our case into work's type-2 based on anatomical location at an angle of mandible, its relationship to parotid gland and facial nerve and previous history of ear discharge. To the best of our knowledge, this is the first case of its type to be reported.

Impacted laryngeal foreign body in a child: a diagnostic and therapeutic challenge.

Impacted laryngeal foreign body could lead to catastrophic consequences if appropriate diagnostic and therapeutic procedures are not promptly instituted. A case of 4-year-old child who presented with a 4-day history of probable ingestion or aspiration of a pen part and history of occasional noisy breathing on exertion and swallowing is reported. On examination, the child appeared asymptomatic on general examination. CT scan of larynx and chest revealed foreign body in the larynx. A conical plastic foreign body in the laryngotracheal junction was retrieved by rigid bronchoscopy. The asymptomatic nature of the foreign body was related to the presence of a lumen within the foreign body permitting ventilation and the inert nature of the material. The case demonstrates the importance of the history, CT scan in case of suspicion, and the need for urgent bronchoscopy with appropriate anesthetic technique.