H. Ikarashi

Suppressed Mastoid Pneumatization in Cholesteatoma

Mastoid pneumatization size was studied by X-ray in 289 patients with otitis media (134 with cholesteatoma and 155 with chronic suppurative otitis media (COM) and 73 patients with traumatic tympanic membrane perforation (controls). The results demonstrated that mastoid pneumatization in the diseased ear of cholesteatoma patients was greatly suppressed. In these patients, the contralateral ear also showed significant suppression compared with controls; mastoid pneumatization size in the healthy ear contralateral to cholesteatoma was similar to that in patients cured of otitis media with effusion (OME). Hence, we conclude that cholesteatoma is a sequela of OME in childhood.

Relation between the Onset of Chronic Middle Ear Inflammation and the Development of the Middle Ear Air Cell System

The relation between the onset of chronic middle ear inflammation and the degree of pneumatization was investigated in porcine tympanic bullae, which closely resemble the human mastoid air cell system. Pneumatization was inhibited in all inflamed ears, and the later the induction of otitis media, the lesser the degree of inhibition of pneumatization. It was concluded that chronic middle ear inflammation inhibits the development of the middle ear air cell system, and the time of onset plays an important role in the degree of pneumatization.