Purpose or Case Report: This review aims to provide a comprehensive visual guide to the imaging features of fetal genitourinary obstructive anomalies. The development of the fetal genitourinary tract is a complex process and, in turn, there are a variety of points in time when the tract may be at risk for the development of malformations. Early diagnosis is crucial for optimizing prenatal care, preventing oligohydramnios, and improving the prognosis and management of affected neonates.
Methods & Materials: Fetal genitourinary anomalies detailed in this educational poster are illustrated using multiple imaging modalities. The abnormalities are described with emphasis on the specific imaging characteristics that help distinguish each entity.
Results: This pictorial review will include educational materials concerning urinary tract obstruction with prenatal and postnatal correlation. An overview of the embryology of fetal genitourinary development will be provided and correlated to the various abnormalities. A review of the urinary tract dilation classification system with prenatal and postnatal examples will also be included. The following specific abnormalities will be discussed: uteropelvic junction obstruction, multicystic dysplastic kidney, duplicated collecting system, ectopic ureter, and ureterocele. Fetal megacystis and its various causes will also be shown, including posterior ureteral valves, Prune Belly syndrome, and megacystis microcolon intestinal hypoperistalsis syndrome. Complications of urinary tract obstruction including urinary ascites, urinoma, and oligohydramnios will also be illustrated. A multimodality approach will be utilized and will include prenatal and postnatal ultrasound, fetal MRI, and postnatal CT, MRI, and nuclear medicine studies, when applicable.
Conclusions: The fetal urinary tract can present a wide variety of potential abnormalities. Recognition of the abnormalities on imaging is crucial for appropriate counseling and management of these patients. This pictorial review enhances early detection and diagnosis of fetal genitourinary anomalies, improving prenatal care and outcomes while aiding in the optimal management of affected neonates.