How is it Diagnosed?
Chronic otitis media (COM) is diagnosed based on a history of recurrent or persistent
middle ear infection with perforation of the tympanic membrane and continuous or
intermittent otorrhea for more than 6–12 weeks. The diagnostic process begins with
clinical history, focusing on ear discharge, hearing loss, previous infections, and prior
ear surgeries.
Otoscopy or pneumatic otoscopy is key to diagnosis. Findings typically include a
perforated tympanic membrane, mucosal thickening, polyp formation, or granulation
tissue in the middle ear. In inactive cases, the tympanic membrane may be intact but
retracted.
Audiometry is performed to assess the degree and type of hearing loss, usually
conductive in nature. Tympanometry helps evaluate middle ear pressure and mobility of
the tympanic membrane, which are often impaired in COM.
Swab cultures of ear discharge may be taken for microbiological evaluation to guide
antibiotic therapy, especially in cases of resistant or persistent infection. Common
organisms include Pseudomonas aeruginosa, Proteus species, and Staphylococcus
aureus.
Imaging such as high-resolution CT of the temporal bone is indicated if cholesteatoma is
suspected or if complications like mastoiditis, facial nerve palsy, or intracranial spread
are present. CT can reveal bone erosion or mastoid air cell involvement.
Classification into mucosal (safe) or squamous (unsafe) types helps in determining the
risk of complications and planning surgical intervention like tympanoplasty or
mastoidectomy.