Comparison of eustachian tube function in children and adults with normal ears.

The eustachian tube function was studied in 53 children and 55 adults, all otologically healthy, by means of typanometry in a pressure chamber. The ability to equilibrate applied overpressures and underpressures in the middle ear by deglutition or jaw movements, ie, muscular opening function was significantly poorer in children than in adults, and also significant poorer in younger children than in older ones. The pressure opening function of the tube was determined during reduction of the pressure in the chamber, ie, deflation test. The relative positive pressure persisting in the middle ear after the deflation test, ie, closing pressure, was also measured. No significant difference was found between children and adults. The ability to create a negative middle ear pressure by sniffing (positive sniffing test) was correlated with low closing pressures of the tube. Children with negative middle ear pressures had poor muscular opening function rather than positive sniffing tests. Judging from serial tympanometric measurements for up to two months, also performed in ten sniffing positive and ten sniffing negative children, it seems that the results obtained in the pressure chamber tests reflect a "mean tubal function."