Beyond ureterolithiasis: gamut of abnormalities affecting the ureter.

Nephrolithiasis is the most common condition involving the ureters. However, various other entities can affect the ureters, albeit less frequently. Imaging plays a crucial role in diagnosis, management, and follow-up of ureteral pathology. In the past decade, computed tomography urography has replaced traditional methods of ureteral imaging due to its high spatial resolution, multiplanar imaging, and rapid acquisition time. More recently, magnetic resonance urography has also been explored in evaluating ureteral abnormalities. In this review, we briefly discuss current imaging techniques used in assessment of the ureters and present a diverse group of diseases affecting the ureters. We begin with primary and secondary ureteral malignancies, followed by uncommon infectious/inflammatory diseases that can involve the ureters including tuberculosis, xanthogranulomatous pyelonephritis, and graft-versus-host disease. We then discuss the imaging characteristics of endometriosis and retroperitoneal fibrosis as two important examples of pelvic and retroperitoneal processes that occasionally obstruct the ureters and present with clinical symptoms similar to that of renal stones. We end with a brief discussion of miscellaneous conditions that affect the ureters, including ureteral hemorrhage, ureteral intussusception, ureteral pseudodiverticulosis, Malacoplakia, and ureteritis cystica. Knowledge of these entities and their characteristic imaging manifestations along with patient's clinical presentation allows accurate diagnosis and timely patient management.