Evaluation of renal artery stenosis with dynamic gadolinium-enhanced MR angiography.

OBJECTIVE The purpose of this study was to compare dynamic gadolinium-enhanced three-dimensional spoiled gradient-recalled MR angiography with conventional arteriography in the evaluation of proximal renal artery stenosis (RAS). MATERIALS AND METHODS MR angiography and conventional arteriographic examinations of 30 patients evaluated for RAS were analyzed retrospectively. Three-dimensional MR angiography was performed with an RF spoiled gradient-recalled imaging sequence acquired during the dynamic i.v. injection of gadolinium (0.2-0.3 mmol/kg), MR data and conventional arteriograms were independently evaluated for the number and location of renal arteries and the degree and location of stenoses. The patients had a mean age of 70 years old and a mean serum creatinine level of 2.9 mg/dl, reflecting a population in whom atherosclerotic RAS was the primary concern. RESULTS Gadolinium-enhanced MR angiography revealed 100% of main renal arteries. For RAS of 50% or greater occlusion, the technique was 100% sensitive and 71% specific; the negative predictive value was 100%. The technique was 100% sensitive and 71% specific for RAS of 75% or greater occlusion. CONCLUSION Dynamic gadolinium-enhanced three-dimensional spoiled gradient-recalled MR angiography has a high sensitivity for revealing proximal RAS and is a quick and reliable technique for obtaining helpful anatomic information.