Abstract
Clinical observation was made on 112 cases of middle ear infection treated by radical mastoide-ctomy.
The air and bone conduction audiometry were done before and after the operation. Objects were divided into five different groups from the degree of the pre-operative air conduction hearing.
In each group, the changes of the post-operative bone and air conduction were studied, and the relationship between the changes of hearing and the state of the tympanic membrane, the impairment of auditory ossicles, the existence of cholesteatoma, and the duration of otorrhoea, were observed.
From the results, the author stated that the pre-operative hearing of chronic suppurative otitsl media treated by radical mastoidectomy was mainly influenced by the state of the perforation of the tympanic membrane, the bone conduction hearing, and the sound transmitting ability of pathologicai conductive apparatus including the ossicles and healty tissues of the middle ear.
