the final section presents tympanometric data from patients with confirmed middle ear pathologies that produce an increase in resonant frequency ( e.g. , middle ear effusion , otosclerosis , ossicular adhesions , and tympanic membrane retraction ) or a decrease in resonant frequency ( e.g. , otitis externa , serous otitis media , tympanic membrane pathology , and ossicular discontinuity ) .
C0013455
middle ear
C0041445
tympanic membrane