Embryonic Connective Tissue in the Tympanic Cavity of the Foetus and the Newborn

Abstract

After a summary description of the formation of the middle-ear cavity and a review of previous studies on the regression of connective tissue in this area, the authors report the results of a pathological study comprising 135 temporal bones from 73 newborn infants. The patients represent mainly the developmental stages corresponding to the last 3 foetal months. The majority had lived only for a very few days.

The middle ear contents consisted of amorphous, loosely fibrillar connective tissue of a fairly uniform degree of differentiation. This content varied rather in quantity, a little more than one-third of the cavities showing fairly narrow, endosteum-like rims of connective tissue and somewhat less than one-third a thicker padding which increased in thickness, especially posteriorly. The remaining approx. 30 % had middle-ear cavities in which the connective tissue occupied more than two-fifths.