Pressure opening and closing functions of the eustachian tube in children and adults with normal ears.

Eustachian tube function was studied with the impedance technique and a pressure chamber in 58 children, aged 3-12 years, and 61 adults, aged 17-73 years, all otologically healthy. The pressure opening and closing functions were measured, i.e. the relative overpressure in the middle ear required to force open the tube, and the residual overpressure in the middle ear after pressure opening, respectively. These "passive" functions of the tube, assumed to reflect the closing factors, did not differ significantly between normal children and adults. The muscular opening function, i.e. "active" pressure equilibration capacity, on the other hand, was significantly poorer in children than in adults and poorer in younger children than in older ones. The results can be used as a reference material in investigations of the Eustachian tube in children with middle ear disease.