Renal artery stenosis and accessory renal arteries: accuracy of detection and visualization with gadolinium-enhanced breath-hold MR angiography.

摘要

PURPOSE: To determine the accuracy of gadolinium-enhanced breath-hold magnetic resonance (MR) angiography in the diagnosis of renal artery stenosis and visualization of accessory renal arteries. MATERIALS AND METHODS: Forty-four patients suspected of having renal artery stenosis and 10 potential kidney donors, all of whom were scheduled to undergo elective intraarterial digital subtraction angiography (DSA), were studied. Three-dimensional gradient-echo gadolinium-enhanced MR angiography was performed at 1.5 T with the following parameters: repetition time, 13.5 msec; echo time, 3.5 msec; flip angle, 60 degrees; 195 x 512 matrix; 400-mm field of view; and 6-cm imaging volume consisting of 15 4-mm-thick partitions reconstructed every 2 mm. Gadopentetate dimeglumine (30 mL) was injected with a power injector. MR angiograms were assessed before the standard of reference, intraarterial DSA, was performed. RESULTS: Four MR angiograms were not evaluable because of poor image quality. MR angiography enabled visualization of all but one of the 121 arteries. In four small accessory arteries, a stenosis could not be excluded owing to inadequate spatial resolution. MR angiography enabled the correct diagnosis in 30 of the 31 arteries with a grade 2 (50%-99%) stenosis and in seven of the 10 occluded arteries. Sensitivity and specificity for correct identification of a grade 2 stenosis were 97% and 92%, respectively. CONCLUSION: Gadolinium-enhanced MR angiography is an accurate, minimally invasive method for detecting renal artery stenosis and is reliable for visualizing accessory renal arteries.