Magnetic Resonance Urography in Evaluation of Duplicated Renal Collecting Systems

Duplex renal collecting systems are common congenital anomalies of the upper urinary tract. Complicated duplex renal systems may require further evaluation using cross-sectional imaging and/or functional imaging after an ultrasound (US) and voiding cystourethrography (VCUG). Functional magnetic resonance urography (fMRU) provides comprehensive morphologic and functional evaluation of duplex kidneys. Magnetic resonance urography (MRU) can demonstrate barely or nonfunctioning renal poles as well as ectopic ureters. fMRU allows better delineation of each pole of a duplex kidney, leading to improved calculation of differential renal function.