Locations of congenital cholesteatoma in the middle ear in Japanese patients

Objectives: To present clinical features of congenital cholesteatoma treated in our institute and to investigate the locations of congenital cholesteatoma in the middle ear of Japanese patients to verify its pathogeneses. Patients and methods: A retrospective chart review of patients in our institute and a review of articles on congenital cholesteatoma reported by Japanese researchers. Charts of the 25 patients with congenital cholesteatoma treated in our institute were reviewed regarding symptoms, locations of cholesteatoma in the middle car, and ossicular anomalies. The same points were investigated in the 71 cases in the Japanese literature. Results: Unlike Westerners, more than half of the Japanese cases had posterior-type cholesteatomas, any parts of which did not exist anteriorly beyond the handle of the malleus. Congenital ossicular anomalies, absence of the long process of the incus, and/or the superior structure of the stapes were seen with a high rate in the Japanese patients. Conclusions: These two findings of the posterior location of cholesteatomas in the middle ear and the high incidence of congenital ossicular anomalies in the Japanese patients suggested that there should be some racial difference in pathogenesis of congenital cholesteatoma. The pathogenesis of congenital cholesteatoma cannot be adequately explained by only one theory alone. It is more appropriate to explain the pathogenesis by using an aggregation of theories. (c) 2005 Elsevier Inc. All rights reserved.