Attic cholesteatoma with closure of the entrance to pars flaccida retraction pocket

We report three patients with pars flaccida-type cholesteatoma (attic cholesteatoma) with closure of the entrance to the cholesteatoma at the time of surgery. These patients were diagnosed with attic cholesteatoma requiring surgery on the basis of abnormal findings of the pars flaccida, audiometry, and temporal bone computed tomography during the clinical course. Intraoperatively, cholesteatoma matrix and granulation tissue were observed behind the intact pars flaccida epithelium, which suggested that the entrance had apparently closed and the continuity with the cholesteatoma matrix disappeared after resolution of inflammation at the pars flaccida. In such patients, a normal pars flaccida may cause cholesteatoma to be initially overlooked, or misdiagnosed as congenital cholesteatoma. The diagnosis should be carefully made on the basis of the clinical course and the results of various examinations.