Changes in Eustachian tube function with age in children with normal ears. A longitudinal study.

A longitudinal study of the Eustachian tube function by different pressure equilibration tests was performed during 11/2-3 years in 44 otologically healthy children, 3-12 years of age. The muscular opening function improved significantly with increasing age. The improvement was most frequent during pre-school ages (3-7 years). Also the tympanometrically measured middle ear pressure, related to the muscular opening function, tended to normalize during the follow-up study. The pressure opening and closing functions, reflecting the tubal closing forces, did not, however, change during the observation time. All the children with poorest muscular opening function at the initial test improved; none developed persistent middle ear disease during the follow-up. Using this standardized exhalation/inhalation test of the pressure equilibrating function of the tube it seems possible to grade the muscular opening function in a valid way. It is argued that the main cause of poor muscular opening function in children is not only due to anatomical differences of the skull base, the tube and peritubal structures but also to the immaturity of the neuromuscular system during childhood.