Abstract
76 operated cases of chronic otitis media were classified into three groups.
Group I: all of pre-operative diagnosis, diagnosis during surgery and histopathological diagnosis were aural cholesteatoma (37 cases).
Group II: one or two of the pre-operative diagnosis, the diagnosis during surgery and the histopathological diagnosis were cholesteatoma (12 cases).
Group III: all of the pre-operative diagnosis, the diagnosis during surgery and the histopathological diagnosis were chronic otitis media without cholesteatoma (27 cases).
Comparing several office examinations of these three groups, otoscopic examination was most useful for confirmation of cholesteatoma. Most cases of Group I had a posterior retraction poket or marginal perforation.
Possibility of misdiagnosis during surgery was that cholesteatoma was not found under a microscope because the size of cholesteatoma was too small or cholesteatoma was intermingled with granulation.
There was a possibility of histopathological misdiagnosis when a mixture of the middle ear tissue and the squamous epithel tissue, such as the outer layer of the tympanic membrane or the skin of the external auditory canal, were submitted for histopathological studies.
The important point was that not only the cases in Group I but also the cases in Group II needed sufficient post-operative observation.
