Comparison of auto-moving table contrast-enhanced 3-D MRA and iodinated contrast-enhanced DSA for evaluating the lower-extremity arteries.
BACKGROUND
This study was conducted to compare diagnostic efficacy of contrast-enhanced 3-dimensional magnetic resonance angiography (3-D MRA) with that of the conventional x-ray iodinated digital subtraction angiography (DSA) in patients with peripheral arterial occlusive diseases (PAOD).


METHODS
Twenty patients with a clinical diagnosis of PAOD participated in this study. All patients were evaluated with both contrast-enhanced 3-D MRA and conventional x-ray iodinated DSA for the arteries of their lower extremities. The DSA was performed by a selective catheterization into the bilateral common or superficial femoral arteries, whereas 3-D MRA was performed with an auto-moving table covering the vascular tree from aorta to the arteries of ankle regions with 1 bolus injection of a triple-dose (0.3 mmol/kg) contrast medium. The arteries were divided into 23 anatomic segments and graded by their appearance on a 1-4 scale (1 = normal, 4 = total occlusion or no visible vessel). Evaluators also compared the images of 3-D MRA with those of the conventional x-ray iodinated DSA (as gold standard) with respect to image quality.


RESULTS
There was a high agreement (k = 0.6-1.0) between 2 observers' interpretations of the images obtained from 3-D MRA and conventional DSA. The agreement within each observer was moderate to fair (k = 0.32-0.57), and the better agreement was found with the images above knee level than those below knee level. As for the image quality of 3-D MRA, the frequencies of showing a similar image quality were 57.5%, 55%, and 37.5% at the aortofemoral, femoropopliteal, and distal leg levels, respectively.


CONCLUSIONS
The main problem of the 3-D contrast enhanced MRA was the returned venous contamination of the image. It was particularly problematic for the areas below knee level. MRA can provide an initial evaluation for patients with PAOD, but cannot substitute for the conventional DSA as a precise diagnostic image modality for peripheral vascular diseases, especially for the distal legs.
Ho
Cheng-Feng
CF
Department of Radiology, Catholic Cardinal Tien Hospital, Taipei, Taiwan, ROC.
Wu
Mei-Han
MH
Wu
Hsiu-Mei
HM
Chang
Cheng-Yeng
CY
Chen
Margaret Chia-Mei
MC
Chou
Ting-Ywan
TY
D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods*; D001157:Arterial Occlusive Diseases / Q000175:diagnosis*; D001158:Arteries / Q000473:pathology*; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D035002:Lower Extremity / Q000098:blood supply; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003287:Contrast Media