Tympanocentesis

Tympanocentesis is the drainage of fluid from the middle ear usually caused by otitis media, by using a small-gauge needle to puncture the tympanic membrane, also known as the eardrum.

Main indication for tympanocentesis is failed treatment with antibiotics

It is sometimes referred to as a "tap" and, when conducted twice as part of a clinical trial of medication, a "double tap."

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