Imaging of the Urachus: Anomalies, Complications, and Mimics

Abstract

Urachal anomalies are more common than previously thought, with more cases discovered incidentally, because of the increased use of cross-sectional imaging. Although an abnormal persistence of an embryologic communication between the bladder and the umbilicus is often recognized and managed in childhood, it may persist into adulthood, with a greater risk of morbidity. Congenital urachal anomalies that are detected early can benefit from an optimized management including surgical approach with a complete resection of the urachal remnant in cases when spontaneous resolution or medical management has failed. At imaging, the different types of urachal anomalies have a distinct appearance. A patent urachus is recognized as an elongated patent connection between the bladder and the umbilicus. An umbilical-urachal sinus is depicted as a blind focal dilatation at the umbilical end, whereas a vesicourachal diverticulum is a focal outpouching at the vesical end. Urachal cysts are visualized as midline fluid-filled sacs most frequently located near the bladder dome. Complications of urachal anomalies have nonspecific clinical findings and can mimic other abdominal and pelvic processes. Potential complications, such as infection and tumors, should be recognized early to ensure optimal management. Understanding of the embryonic development of the urachus is necessary for the radiologist to diagnose the wide variety of urachal disease. RSNA, 2016.

Evaluation and management of urachal remnants in children

“…16 Ultrasonography, CT, voiding cystoureterogram, and fistulography can be used for the diagnosis of urachal anomalies. 17 Ultrasonography is the first imaging method that should be preferred for urachus and urachal anomalies because it has a shorter turnover time without exposure to radiation and it is easily accessible. 18 In the detection of urachal anomalies by USG, a positive predictive value of 83% and a sensitivity of 79% were found.…”

Ultrasound findings of urachal anomalies. A series of interesting cases

“…Various imaging modalities can be performed to diagnose the suspected urachal anomalies, including US, CT, MRI and fistulogram [8]. US is the preferred imaging tool in clinical settings, because it is fast, readily available, without radiation, which is very important in children and young adults [9].…”

“…A high positive predictive value of 83% and a sensitivity of 79% of US in the detection of the urachal anomalies was reported [10], over 90% in early childhood [11]. If US findings are not sufficient, the other imaging modalities can be recommended [8,12,13].…”

Strangulated Umbilical Herniation into Urachal Anomaly

“…Urachal anomaly results from a failure of the urachus to regress and is a rare congenital disorder. Urachal remnants are classified into four categories: patent urachus, urachal cyst, umbilical-urachal sinus, and vesicourachal diverticulum [1]. The most frequent complication of urachal remnants is infection.…”

“…This article is part of the Topical Collection on Surgery * Shoichi Sasaki dsasaki@dokkyomed.ac.jp Patent urachus is the most common type and 47% of urachal remnant. The second common type is urachal cyst (30%), followed by umbilical-urachal sinus (18%), and vesicourachal diverticulum (3%)[1]. Infection is the most frequent complication of urachal remnant.…”