Evaluation of renovascular hypertension: comparison of functional MRI and contrast-enhanced MRA with a routinely performed renal scintigraphy and DSA

OBJECTIVE: The main objective of this study was to evaluate a clinically suspected renovascular hypertension (RVH) by means of MRI. It was to find out if functional MRI (fMRI) is able to provide adequate results with regard to MAG3 captopril scintigraphy and if contrast-enhanced MR angiography (MRA) is able to provide adequate results in the stenosis grading compared with the nonselective digital subtraction angiography (DSA). METHODS: This open, monocentric, prospective, phase 3 study included patients with a clinically suspected RVH. For fMRI a dynamic TurboFLASH sequence and for MRA a single-shot breath-hold flash 3D sequence was performed. Gadodiamide was injected as contrast medium. RESULTS: Sixty patients were included in the study. The correlation between fMRI and scintigraphy had an accuracy, a sensitivity, and a specificity of 69%, 5%, and 92%, respectively, and correlations between MRA and DSA of 95%, 92%, and 96%. CONCLUSION: The noninvasive MRA can replace DSA in the diagnosis of renal artery stenosis. However, fMRI can not replace renal scintigraphy.