Radiological Analysis of the Facial Recess: Impact on Posterior Tympanotomy Difficulty During Pediatric Cochlear Implantation

Abstract

Objectives We analyzed several radiological features of the facial recess to correlate them with the intraoperative findings to highlight the most reliable predictors of posterior tympanotomy difficulty. Study Design Retrospective observational cohort study. Setting Multicenter study at tertiary referral institutions. Methods We included 184 pediatric patients who underwent cochlear implantation through the posterior tympanotomy approach. The correlation was attempted between 8 radiological features in the preoperative high-resolution computed tomography scan and intraoperative surgical difficulty. Results Posterior tympanotomy was straightforward in 136 (73.9%) patients. In contrast, it was challenging in 48 (26.1%) patients. The facial recess was aerated in 74.5% of patients. The mean (SD) posterior tympanotomy depth was 3.98 (0.867) mm. The mean (SD) chorda-facial angle was 27.67° (3.406°). The mean (SD) chorda-facial to stylomastoid length was 3.898 (0.6304) mm. The mean (SD) facial nerve second genu angle was 94.54° (6.631)°. Deep-unaerated facial recess wall was associated with the most difficulty. There was a statistically significant difference in the unchallenging and challenging posterior tympanotomy groups regarding the surgical duration ( P < .0001). Conclusions According to this analytic study, the chorda-facial angle, the facial recess aeration, and the chorda-facial to stylomastoid length were respectively the strongest preoperative radiological predictors of the surgical difficulty of posterior tympanotomy during cochlear implantation. Chorda-facial angle <25.5° was associated with difficult posterior tympanotomy. The oblique parasagittal cut was essential for the radiological analysis of the facial recess.

Localization of the Vertical Part of the Facial Nerve in the High-Resolution Computed Tomography During Pediatric Cochlear Implantation

“…Although both the anterior and lateral displacement of the VPFN may affect the RW accessibility, Elzayat et al found that the PT difficulty was statistically related more to the lateral displacement of the VPFN in their radiological analysis of the FR and evaluating its impact on the CI surgery. 14 …”