The human Eustachian tube lumen in children. I. The isthmus.

A study of Eustachian tube measurement in infants and children is presented. The study comprised 53 Eustachian tubes from normal temporal bones and 17 Eustachian tubes from temporal bones harbouring acute and secretory otitis media. The temporal bones underwent histologic serial sectioning. The lumen of the Eustachian tube isthmus was measured with the aid of a grid mounted on a microscope. These measurements show: A) the Eustachian tube isthmus lumen does grow and enlarge slightly with age; B) each age group presents a considerable range in area, compatible with a natural biological distribution; C) no statistical difference was found in the size of isthmus lumens obtained from temporal bones which had been affected by acute or secretory otitis media, when compared with lumens of Eustachian tubes coming from non-pathological ears. This comparison took into consideration both age and physiological distribution.