Objective: To find out the features of the temporal bone high resolution computer tomography (HRCT) of the congenital cholesteatoma of middle ear.
Method: The HRCT image of 29 patients (30 ears) of congenital middle ear cholesteatoma were reviewed retrospectively and the location of the lesion, the type of mass, the erosion of the ossicular chain and other malformation of the middle ear were Investigated. All of the cases were confirmed by operation and pathyology.
Result: Of these 29 patients (30 ears) with congenital middle ear cholesteatoma, the cholesteatoma localized to the tympanic cavity in 18 patients while the mastoid cavity was involved together with the tympanum in 12 ears. According to the shape of the mass, 21 cases were classified as open type while the other 9 cases were close type. The ossicles were affected in all of these patients. Erosion of the long process of the incus combined with super structure of the stapes, which was detected in 29 ears, was most common.
Congenital malformation of ossicular chain was found accompanied with the cholesteatoma in 3 cases. In addition, abnormal hyperosteogeny was seen in 2 cases. The facial nerve canal erosion was identified in 3 cases and the semicircular canal fistula was found only in 1 patient.
Conclusion: Temporal bone HRCT was very helpful for the early diagnosis of the congenital middle ear cholesteatoma. The open type cholesteatoma were much more common than the close type in our clinic. Other malformation of the middle ear sometimes could be found with the congenital middle ear cholesteaoma together.