Natural History of Obstructed and Pseudo‐obstructed Megaureters Detected by Prenatal Ultrasonography

Summary— In a series of 38 patients with non‐refluxing megaureters detected by prenatal ultrasonography, 89% were males and 16% had associated ipsilateral or contralateral urinary anomalies. By renographic criteria, 36% of ureters were not obstructed; renal function was never impaired initially and, on follow‐up, spontaneous resolution of dilatation was common. Infective urinary calculi developed in 3 of the boys. In ureters obstructed by renographic or pressure‐perfusion criteria, 79% exhibited normal renal function initially. Most such patients were managed expectantly; on follow‐up, functional deterioration occurred in 2 patients, while in the remainder dilatation usually persists but without change in function.