Open vs closed type congenital cholesteatoma of the middle ear: two distinct entities or two aspects of the same phenomenon?

Abstract Objective The clinical features and surgical results of “closed type” versus “open type” congenital cholesteatoma were compared in order to analyse the differences between the two forms; whether the morphology of the disease may have a role in the staging systems has been also evaluated. Patients and methods We reviewed retrospectively 95 patients (96 ears) who underwent surgery for congenital cholesteatoma over a 15-year period focusing on the clinical differences between open and closed type congenital cholesteatoma. Results Seventy-one patients (74%) had a closed-type and 25 (26%) an open type congenital cholesteatoma. Our study confirmed the higher prevalence of the closed type, as well as, a younger age at initial diagnosis compared with the open type congenital cholesteatoma. Other differences between the two forms were: modality of diagnosis (pathognomonic otoscopy in 100% of the closed type and in 40% of the open type), positive history for otitis media with effusion (51.4% in closed type vs 20% in open type), involvement of the tympanic membrane quadrants (anterior quadrants were more frequently involved in the closed forms, whereas posterior quadrants were more frequently involved in the open forms), disease extension and aggressiveness. A residual cholesteatoma was found in 6 out of the 71 patients (8.4%) with a closed type congenital cholesteatoma and in 10 out of the 25 patients (40%) with an open type congenital cholesteatoma. After adjusting for potential confounders, open-type congenital cholesteatoma was significantly associated with residual cholesteatoma compared to the closed-type (odds ratio [OR] 7.39, 95% confidence interval [CI] 1.10–49.77, p = 0.03). Conclusion This study confirmed that the open congenital cholesteatoma has global clinical features that are uniquely different from the classical closed form. These differences could reflect a distinct pathogenesis, but there is no proof of this to date. The classification of the congenital cholesteatoma could be further refined by adding the morphologic type of the disease.