Postnatal development of Eustachian tube: A computer-aided 3-D reconstruction and measurement study

The postnatal development of the Eustachian tube (ET) and its surrounding s tructures was investigated by means of computer-aided three-dimensional (3- D) reconstruction methods in 13 normal human temporal bones, obtained from individuals 3 months to 71 years old. The cross-sectional area, width and h eight of the lumen in most of the cartilaginous portion of the ET were sign ificantly smaller in children than in adults. In particular, there was a ma rked, age-associated difference in the shape of the lumen in the cartilagin ous portion of the ET. In adults, the cross-sectional area of the lumen dec lined monotonically between a large opening at the pharyngeal orifice and t he narrowest portion of the ET (near the border of the cartilaginous and ju nctional regions). In children, by contrast, the ET lumen was uniformly sma ller over the first 80% of its length from the pharyngeal orifice. It is su ggested that this immature morphology of the ET lumen may confer increased risk of developing otitis media during childhood.