CLINICAL STUDIES ON CHRONIC OTITIS MEDIA WITH OR WITHOUT CHOLESTEATOMA

OSSICULAR DAMAGE

Abstract

This study included 109 cases of chronic otitis media with cholesteatoma (pars flaccida type, 69 cases pars tensa type, 27 cases and others, 13 cases) and 160 cases of chronic otitis media without cholesteatoma. The results of the present study are as follows:
1. The location of ossicular erosion was mostly at the region where a cholesteatoma matrix had invaded. It was recognized that the lateral side of the malleus and incus were usually found to have been resorbed at the early stage, followed by the destruction of malleus head, incus body and short process in the cholesteatoma of pars flaccida type. On the other hand, the medial side of the malleus and incus including I-S joint were usually found to have been resorbed in the cholesteatoma of pars tensa type at the early stage. Generally, the extent of ossicular erosion in the cholesteatoma of pars tensa type is much more severe than that of pars flaccida type, therefore, all the ossicles had completely disappeared in many cases with pars tensa type. It was noted that the resorption had been found mainly about the I-S joint in chronic otitis media without cholesteatoma.
2. The bony walls of the mastoid cavity were frequently resorbed in the cholesteatoma of pars flaccida type. The bony walls of the hotizontal portion of the facial nerve were resorbed in the cholesteatoma of pars tensa type.
3. The I-S joint was frequently resorbed as a result of the presence of severe inflammatory changes at the postero-superior portion of the tympanic cavity in chronic otitis media without cholesteatoma.