The phenomenonof obstruction to the normal flow of urine due to the presence of structural orfunctional changes in the urinary tract is known as Obstructive uropathy. It isdue to functional or anatomic lesions that can be located anywhere in theurinary tract.Varioustechniques had been described to demonstrate urinary tract. However, only CTUrography and MR Urography has ability to describe entire urinary system alongwith surrounding structures.1Hennig Jdescribed Magnetic resonance urography (MRU) in 1987 at the University Hospitalof Freiburg Germany, as a complementary method to evaluate urinary tractabnormalities.2 Techniqueof MR urographic for demonstration of the urinary tract can be divided into twocategories: static-fluid MR urography and excretory MR urography.
Due to the long T2relaxation time of fluid in the collecting system, heavily T2-weightedsequences have been used instatic-fluid MR urography to image the urinary tract as a static collection offluid. This can be repeatedwith cine MR urography to confirm stenosis. Excretory MR urography is performed with the help of intravenousadministration of gadolinium contrast during excretory phase.
Diureticadministration can be useful in excretory MR urography in demonstration ofnondilated collecting systems.3,4MRU provides a non-invasive visualization notonly of the collecting system but also of the renal parenchyma using fast spin-echopulse sequences as well.The present study evaluates the cause and level of urinaryobstruction in patients with obstructive uropathy using MR Urography andcorrelates it with the intra-operative findings and clinical follow-up.