Many patients being followed for chronic suppuration of the middle ear were observed to have sensorineural or mixed type hearing loss.
The major cause of this bone conduction loss might be secondary to cochlear biochemical changes occuring through the round window membrane. But, clinical and statistical analysis of bone conduction loss in chronic otitis media has not been
exactly
reported until now. Authors studied the relationship between the preoperative bone conduction hearing level and age, nature of middle ear and temporal bone pathology, pneumatization of mastoid in 97 ears of chronic suppurative otitis media
performed
media performed middle ear surgery at Konkuk University Hospital from March 1992 to December 1993.
@ES The results were as following:
@EN The mean bone conduction threshold was 16.2±12.4dB. In the cases of ossicular defect, bone conduction loss was greater in total destruction than in partial destruction with statistical significance. Among ossicular defect, incus destruction
group
showed more bone conduction loss than intact incus group with statistical significance. There was no difference of bone conduction loss according to pathologic findings in middle ear cavity and mastoid antrum, but pathologic groups showed more
bone
conduction loss than control group with normal temporal bone pneumatization with statistical significance. Comparing pneumatization of mastoid antrum and mastoid process, there was statistically significant bone conduction loss in orders of
pneumatic
type, diploic type, sclerotic type, cholesteatoma cavity. There was no difference of bone conduction hearing level according to age, sex, and duration of disease process with statistical significance. The results suggest that the bone conduction
threshold in chronic otitis media is influenced by artificial elevation due to conductive defect and can be improved by reconstructive surgery.
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