Congenital ureteral strictures

A comparative study was made of pathologic ureteral segments taken from patients with the diagnosis of congenital ureteropelvic junction obstruction, congenital megaureter, and ureteral achalasia. This study indicated that the basic problem was one of disordered muscularization of the involved segment. Muscle fibers were reduced in number in relation to an increased amount of collagen; muscle-to-muscle contact was poor or nonexistent in many cases. The muscle proximal to the involved segment was hypertrophied in the same manner as in any obstructed ureter.