Diseases of The Middle Ear
Secretory otitis media is diagnosed by: [PGI June 08]
|B||Pure tone audiometry|
a. Pure tone audiometry: gives-information about the quantity and quality of hearing loss.
b. In secretory otitis media; conductive deafness of 20-40 dB is seen (which is not a specific finding as conductive deafness can be seen in many other conditions). Therefore, pure tone audiometry is not diagnosticof serous otitis media but provides an assessment of the hearing loss and is therefore important in monitoring the progress of the condition and provides information useful for management decisions
c. On otoscopy: Tympanic membrane appears dull, opaque with loss of light reflex(which again isnot diagnostic).
d. X-ray mastoid: Shows clouding of air cells.
e. Impedance audiometry is an accurate way of diagnosing serous otitis mediA.ltshows type B tympanoqram which is diagnostic of fluid in ear",