Introduction

Abstract

Congenital anomalies of the upper urinary tract are common in children and adults. These anomalies are classified into anomalies of the kidney and anomalies of the renal pelvis and ureter. Anomalies of the kidney include renal agenesis and hypoplasia, renal ectopia and anomalies of fusion, anomalies of rotation, and anomalies of the renal calyces. Anomalies of the renal pelvis and ureter encompass congenital ureteropelvic junction obstruction, congenital megaureter, circumcaval ureter, duplication of collecting system, ureterocele, and ectopic ureteral insertion. Because most of this disorder originates from a series of abnormal embryological processes, it is important to understand multiple associated abnormalities of certain congenital anomalies in the upper urinary tract. Multimodality imaging, such as computed tomography (CT), magnetic resonance imaging (MRI), ultrasonography (US), and intravenous urography (IVU), have been required to evaluate a spectrum of the disorder. This chapter presents various imaging findings of the congenital anomalies of the urinary tract.