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The objective of the study was to prove the value of single-dose contrast-enhanced magnetic resonance angiography [three-dimensional (3D) ceMRA] in abdominal and iliac arteries versus the reference standard intra-arterial digital subtraction angiography (i.a.DSA) when indicating a therapy. Patients suspected of having abdominal or iliac artery stenosis were included in this study. A positive vote of the local Ethics Committe was given. After written informed consent was obtained, 37 patients were enrolled, of which 34 were available for image evaluation. Both 3D ceMRA and i.a. DSA were performed for each patient. The dosage for 3D ceMRA was 0.1 mmol/kg body weight in a 1.5-T scanner with a phased-array coil. The parameters of the 3D-FLASH sequence were as follows: TR/TE 4.6/1.8 ms, effective thickness 3.5 mm, matrix 512 x 200, flip angle 30 degrees , field of view 420 mm, TA 23 s, coronal scan orientation. Totally, 476 vessel segments were evaluated for stenosis degree by two radiologists in a consensus fashion in a blinded read. For each patient, a therapy was proposed, if clinically indicated. Sensitivity, specificity, positive and negative predictive values, and accuracy for stenoses > or = 50% were 68%, 92%, 44%, 97%, and 90%, respectively. In 13/34 patients, a discrepancy was found concerning therapy decisions based on MRA findings versus therapy decisions based on the reference standard DSA. The results showed that the used MRA imaging technique of abdominal and iliac arteries is not competitive to i.a. DSA, with a high rate of misinterpretation of the MRAs resulting in incorrect therapies.

Purpose: The goal of this work was to test the ability of a combination of 2D phase-contrast MR angiography (2D-PC-MRA) and triggered 2D time-of-flight MRA (2D-TOF-MRA) in comparison to intraarterial digital subtraction angiography (DSA) to correctly diagnose the location and shape of occlusive lesions in the iliac and femoral arteries and to determine whether 2D-TOF-MRA is helpful to clarify questionable lesions demonstrated by 2D-PC-MRA., Methods: In 50 patients with claudication, 2D-PC-MRA was performed in three consecutive coronal positions from the aortic bifurcation to below the trifurcation. Axial 2D-TOF-MRA was performed additionally at the site of detected lesions of >50% and lesions in doubt to obtain more precise information about the stenosis. Lesions were classified as follows: low grade occlusion, <50%; high grade occlusion, >50%. MRA was performed within 24 h of a DSA examination., Results: In all patients, the arterial tree from the aortic bifurcation to the trifurcation could be visualized. One hundred twelve lesions were detected by MRA. Sensitivity was 96% and specificity was 92%. Sixty-two lesions were classified as high grade occlusion and reevaluated. In this category, sensitivity was 100% and specificity was 96%., Conclusion: The combination of 2D-PC-MRA with triggered 2D-TOF-MRA detects stenotic lesions in the lower extremity arterial system with high sensitivity and specificity.

The purpose of this study was to evaluate the capability of contrast-enhanced breath-hold fast imaging with steady-state precession (FISP) three-dimensional MR angiography (MRA) to detect stenotic lesions of the abdominal aorta, the renal arteries, and the iliac arteries by using a K-space-centered 20-ml gadolinium-diethylene pentaacetic acid (Gd-DTPA) bolus. Fifty patients were studied before conventional x-ray angiography. Contrast-enhanced breath-hold FISP three-dimensional MRA was applied in the coronal view, centered at the renal arteries. Twenty ml of Gd-DTPA was used in all subjects. A test bolus was applied to determine the injection time for the K-space-centered bolus injection. Of 300 segments, 284 segments were classified correctly, 11 were overestimated, and five were underestimated. Sensitivity was 98%, specificity was 96%, positive predictive value was 96%, negative predictive value was 98%, and accuracy was 97%. Of the 50 patients studied, 43 were staged correctly. No venous overlay was seen in 31 patients; partial overlay was seen in 16 patients, and venous structure overlay obscuring arterial anatomy was found in two patients. Six of nine accessory renal arteries could be identified by MRA. Intraobserver variability was .94. This study has shown the ability of contrast-enhanced breath-hold FISP three-dimensional MRA to detect and grade vascular lesions in the abdominal aorta and the renal arteries. The method may serve as a screening tool in the future.