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Cholesteatoma Localization in the Contralateral Ear

Objective: Acquired cholesteatoma has been extensively studied. Theories that involve previous tympanic membrane retractions in the cholesteatoma pathogenesis are the most accepted. However we do not know what happens in the contralateral ear. We want to evaluate and compare the localization of acquired cholesteatomas in patients with bilateral disease. Method: This is a transversal study. We evaluated 1,015 patients with chronic otitis media in at least one ear and no previous surgery between August 2000 and January 2011. Otoendoscopy was carried out and recorded on the affected ear just as in the contralateral, which was classified. Results: Two hundred and sixty patients with chronic otitis media with cholesteatoma were included. The mean age was 31.7 years, and 52.7% were male. Cholesteatoma was found in 17% of the contralateral ears. In the case of an epitympanic cholesteatoma in one ear, the cholesteatoma in the other ear was in the same site in 92% of patients. On the other hand, if it was mesotympanic posterior in one ear, the cholesteatoma in the contralateral ear was in the same location in 80%. Conclusion: The results suggest that patients with acquired cholesteatoma have a greater probability of having a cholesteatoma in the same site in the contralateral ear. This corroborates the idea that chronic otitis media with cholesteatoma is not only an isolated event but a constitutional process with a high prevalence of bilaterality.