High-spatial-resolution contrast-enhanced MR angiography of abdominal arteries with parallel acquisition at 3.0 T: initial experience in 32 patients.
OBJECTIVE
The objective of our study was to evaluate an isotropic high-spatial-resolution 3D contrast-enhanced MR angiography (CE-MRA) protocol with high acceleration parallel acquisition at 3.0 T for the display of the abdominal vasculature.


METHODS
Thirty-two consecutive patients (13 men, 19 women; age range, 28-88 years) with suspected abdominal arterial disease underwent abdominal 3D CE-MRA on a 3.0-T MR system, using a high-spatial-resolution (0.7 x 0.82 x 0.8 mm3) 3D gradient-refocused echo (GRE) sequence, integrated with a generalized autocalibrating partially parallel acquisitions (GRAPPA) technique with an acceleration factor of 3. Two vascular radiologists evaluated image quality and the presence and degree of arterial stenoses. Interobserver variability was calculated, using the kappa coefficient. The sensitivity and specificity of the technique were calculated and comparative analysis was performed with those of conventional catheter angiography (in eight patients) as the standard of reference.


RESULTS
The abdominal arterial vasculature was visualized with diagnostic image quality in all subjects. Arterial stenoses were detected in 148 and 142 arterial segments by observer 1 and observer 2, respectively, with good interobserver agreement (kappa = 0.75; 95% confidence interval [CI]: 0.69-0.81). The sensitivity and specificity values for CE-MRA for the detection of significant (> 50%) arterial stenoses were 100% and 96% for observer 1 and 100% and 92% for observer 2, respectively. There was a significant correlation between CE-MRA and conventional angiography (R = 0.96 and 0.93 for observers 1 and 2, respectively) for the assessment of the degree of stenosis.


CONCLUSIONS
The outlined MR angiography protocol at 3.0 T combined with parallel acquisition technique renders highly reliable and isotropic high-spatial-resolution imaging of the abdominal vasculature.
Nael
Kambiz
K
Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, 10945 Le Conte Ave., Ste. 3371, Los Angeles, CA 90095, USA. nkambiz@mednet.ucla.edu
Saleh
Roya
R
Lee
Margaret
M
McNamara
Thomas
T
Godinez
Sergio R
SR
Laub
Gerhard
G
Finn
J Paul
JP
Ruehm
Stefan G
SG
D000005:Abdomen / Q000098:blood supply*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries; D003287:Contrast Media; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D015588:Observer Variation
D003287:Contrast Media