Middle ear effusion (滲出性中耳炎)

Aetiology:
Middle ear effusion is often associated with Eustachian tube obstruction, either acute during upper respiratory infections or chronic as in childhood adenoid hypertrophy. In adults middle ear effusion may result from Eustachian tube obstruction by a nasopharyngeal neoplasm. Changes in atmospheric pressure occurring during flight or diving may also result in effusions: otitic barotrauma.

Incidence:
Middle ear effusion is a common pediatric problem, particularly in the 4-7age group.

Clinical features:
On otoscopy the tympanic membrane is dull with a loss of light reflex. Small vessels are often seen radiating from the handle of the malleus and occasionally a fluid level is seen. Deafness in children may lead to poor language development and educational performance. Diagnosis may be confirmed by impedance audiometry in which the compliance of the tympanic membrane is measured in response to pressure changes in the external auditory meatus.

Management:
Medical treatment – consists of the use of topical and systemic decongestants.

Surgical treatment – consists of myringotomy and insertion of a ventilation tube into the affected tympanic membrane. Children may also require an adenoidectomy whilst in adults a nasopharyngeal tumor must be excluded.