Role of Sonography and Magnetic Resonance Imaging in the Assessment of Fetal Genitourinary Tract Anomalies

Abstract

Anomalies of the genitourinary system are the most common congenital anomalies & account for 14-40 % of all anomalies that can be detected prenatally. The primary imaging modality used to visualize the fetal urogenital tract antenatally is ultrasound because of its low cost, availability and non invasive imaging. Sonography is an accurate method of evaluating the fetal genitourinary system. However, factors such as body habitus, fetal position, and oligohydramnios can prevent optimal sonographic visualization. Fetal magnetic resonance imaging (MRI) is being increasingly used to evaluate cases with sonographically suspected genitourinary anomalies and associated extrarenal fetal anomalies with high accuracy especially in cases with oligohydramnios or anhydramnios. New MRI technologies provide faster scan times with better resolution, increasing the applications for fetal imaging. Superior soft tissue contrast, relative operator independence, and a large field of view are factors that allow easy understanding of the relationship between adjacent structures with excellent anatomic details. Detection of fetal anomalies Permits improved management of the pregnancy and better counseling of parents and preparation of health care teams at delivery and is of great use in postnatal decision making.