Facial canal dehiscence in patients undergoing surgery for chronic otitis media: analysis of 850 patients

ntroductionIn all otologic surgeries, the facial nerve can be considered the most important structure that must be protected. The surgical damage risk of the facial nerve will be increased in presence of facial canal dehiscence (FCD).AimIn this study, we aimed to evaluate the FCD and its associated situations in patients with chronic otitis media undergoing mastoidectomy.Materials and Methods850 patients who performed ear surgery were reviewed. Patients who did not perform mastoidectomy were excluded. In patients, the ratios, localization of FCD, and association of facial canal dehiscence with cholesteatoma were researched. Association between FCD and closed-cavity tympanomastoidectomy, open-cavity tympanomastoidectomy, and radical mastoidectomy procedures, and also an association between FCD and primary or revision surgery was evaluated. ResultsFacial canal dehiscence was found in 8.4% of patients. The relationship between dehiscence and cholesteatoma was found significant (p<0.001). In the comparison of radical mastoidectomy and closed-cavity tympanomastoidectomy, dehiscence was higher in the radical mastoidectomy group (p<0.03). In revision cases, dehiscence was seen more frequently (p<0.003). FCD incidence was higher in adult patients than in pediatric patients (p<0.001). Twenty of 468 patients who were operated on for cholesteatoma had congenital cholesteatoma. ConclusionFacial canal dehiscence can be seen especially in cases with cholesteatoma and when performing radical mastoidectomy and revision surgeries. Therefore, a detailed evaluation of the status of facial nerve and determination of situations in which occurrence of FCD is more likely both preoperatively and intraoperatively will minimalize potential complications.Keywords: Cholesteatoma, tympanic, radical mastoidectomy, oval window, tympanomastoidectomy.