A classification and quantitative histological study of abnormal ureters in children.

Abstract

SummaryA gross and quantitative study of the muscle and connective tissue and elastic tissue has been carried out on a series of 78 abnormal ureters in children.The ureters have been classified into 5 classes: (A) normal; (B) ureters with irregular dilatations; (C) slightly dilated ureters with muscular hypertrophy and hyperplasia; (D) elongated and dilated ureters with muscular hypertrophy and hyperplasia but probably decompensated; (E) grossly distended and elongated ureters having an increase in elastic tissue but with no comparable muscular hypertrophy or hyperplasia.Ureters showing structural changes do so uniformly throughout their length and no local anatomical deformities were found to account for the irregularities in the ureters of Class B.Structurally incompetent uretero‐vesical junctions are only associated with ureters of Classes D and E.All abnormal ureters show varying degrees of muscular hypertrophy and hyperplasia. It is suggested that the form of the ureter is related to whether or not the muscular hypertrophy is adequate to compensate for the increased luminal diameter.