Intramembranous and mesotympanic cholesteatomas associated with an intact tympanic membrane in children.

A series of 15 intramembranous (IMTC) and mesotympanic (MTC) cholesteatomas associated with intact tympanic membranes in children is presented. Clinical observations, audiometric and radiographic data, and surgical findings are correlated. A history of recurrent otitis media was obtained in 85% (13/15) of the cases, differentiating them from the usual congenital cholesteatomas. The possibility that many of these are indeed "acquired" lesions is emphasized. Hypothetical pathogenetic mechanisms are discussed. The basal cell papillary proliferation theory is considered the most attractive explanation of the development of both IMTCs and MTCs. The need for careful, prolonged, follow-up otoscopic examination of children with recurrent otitis media is stressed, if more of these lesions are to be recognized early.