術後性乳突腔真珠腫の2症例

抄録

Two cases of mastoid cavity cholesteatoma which occurred many years after the middle ear surgery, are reported. The patients were a 36 year-old male and a 32 year-old female who had undergone middle ear surgery for otitis media when they were 13 years old and 15 months old, respectively. In these patients, cholesteatoma was confined to the mastoid cavity, and was supposed to be induced by extension of the canal skin through the bony defect in the external part of the posterior-superior wall of the ear canal. The bony defect was probably created by the previous operation or occurred due to canal wall resorption after the operation.