Symptomatic peripheral vascular tree stenosis. Comparison of subtracted and nonsubtracted 3D contrast-enhanced MR angiography with fat suppression.
OBJECTIVE
To determine the clinical feasibility of contrast-enhanced three-dimensional (3D) MR angiography (MRA) with fat suppression spectral inversion at lipids and to compare subtracted and nonsubtracted images.


METHODS
In 13 patients suspected of having lower extremity ischemia, 3D dynamic contrast-enhanced MRA of the iliac and femoral arteries was performed using the fat suppression technique. The validity of the MRA interpretations of the degree of stenoses was evaluated by comparing with conventional angiography as the gold standard. The contrast-to-noise (C/N) ratios of both subtracted and nonsubtracted maximum-intensity-projection (MIP) images were calculated.


RESULTS
In the arteries with stenosis of 50% or greater, the sensitivity and specificity of the subtracted MR angiograms were 100% and 96.5%, respectively, not significantly different from the corresponding values in nonsubtracted MRAs (100% and 94.1%, respectively). The C/N ratios of the subtracted images were significantly higher than those of the nonsubtracted images (p<0.001).


CONCLUSIONS
With this technique, fat suppression can be performed with only a slight increase in the examination time. A lower dose of contrast material can be used in MRA with fat suppression than without it. Subtracted MRA improves the ease of interpretation compared to nonsubtracted MRA.
Sueyoshi
E
E
Department of Radiology, Nagasaki University School of Medicine, Japan.
Sakamoto
I
I
Matsuoka
Y
Y
Hayashi
H
H
Hayashi
K
K
D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D001157:Arterial Occlusive Diseases / Q000175:diagnosis*; D003287:Contrast Media; D005240:Feasibility Studies; D005260:Female; D005263:Femoral Artery / Q000473:pathology; D019786:Gadolinium DTPA; D006801:Humans; D007083:Iliac Artery / Q000473:pathology; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D007383:Intermittent Claudication / Q000175:diagnosis; D007511:Ischemia / Q000175:diagnosis; D007866:Leg / Q000098:blood supply*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
D003287:Contrast Media; D019786:Gadolinium DTPA