Accuracy of tympanometric middle ear pressure determination in secretory otitis media: dose-dependent overestimation related to the viscosity and amount of middle ear fluid.

Hypothesis: Tympanometric measurements of middle ear pressure in children with secretory otitis media are overestimated in a dose-response manner because of increased hysteresis explained by the viscosity and amount of middle ear fluid.

Background: Tympanometric middle ear pressure is important in evaluating children with secretory otitis media. These measurements are influenced by hysteresis appearing as a peak pressure difference in bidirectional tympanometry.