3 T contrast-enhanced magnetic resonance angiography for evaluation of the intracranial arteries: comparison with time-of-flight magnetic resonance angiography and multislice computed tomography angiography.
OBJECTIVE
We sought to prospectively evaluate the image quality and visualization of the intracranial arteries using high spatial resolution contrast-enhanced magnetic resonance angiography (CE-MRA) at 3 T and to perform intraindividual comparison with time-of-flight (TOF) MRA and multislice CT angiography (CTA).


METHODS
Twelve patients (5 men, 7 women, 37-71 years of age) with suspected cerebrovascular disease prospectively underwent MRA and CTA. MRA was performed on a 3 T MR system, including both 3-dimensional (3D) TOF (Voxel dimension: 0.6 x 0.5 x 0.9 mm in 5 minutes and 40 seconds) and 3D CE-MRA (voxel dimension: 0.7 x 0.7 x 0.8 mm in 20 seconds, using parallel acquisition with an acceleration factor of 4). CTA images were acquired on a 16-slice CT scanner (voxel dimension: 0.35 x 0.35 x 0.8 mm in 17 seconds). The image quality and visualization of up to 26 intracranial arterial segments in each study was evaluated by 2 experienced radiologists. The arterial diameter for selective intracranial arteries was measured independently on each of the 3 studies, and statistical analysis and comparative correlation was performed.


RESULTS
A total of 312 arterial segments were examined by CE-MRA, TOF-MRA, and CTA. The majority of intracranial arteries (87%) were visualized with diagnostic image quality on CE-MRA with a significant correlation to TOF (R values = 0.84; 95% confidence interval 0.79-0.86, P < 0.0001), and to CTA (R values = 0.74; 95% confidence interavl 0.68-0.78, P < 0.001). The image quality for small intracranial arteries, including the anterior-inferior cerebellar artery, the posterior communicating artery, and the M3 branch of the middle cerebral artery, was significantly lower on CE-MRA compared with TOF and CTA (P < 0.03). There was a significant correlation for the dimensional measurements of arterial diameters at CE-MRA with TOF (r = 0.88, 95% confidence interval 0.81-0.93), and CTA (r = 0.83, 95% confidence interval 0.73-0.90).


CONCLUSIONS
The described 3 T CE-MRA protocol, spanning from the cervical to the intracranial vessels, visualized and characterized the majority of intracranial arteries with image quality comparable with that obtained using TOF-MRA and CTA. Further clinical studies are required to establish the accuracy of the technique in a broader clinical setting.
Villablanca
J Pablo
JP
Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California 90095-7206, USA.
Nael
Kambiz
K
Habibi
Reza
R
Nael
Ali
A
Laub
Gerhard
G
Finn
J Paul
JP
D000328:Adult; D000368:Aged; D002533:Cerebral Angiography / Q000295:instrumentation* / Q000379:methods*; D002536:Cerebral Arteries / Q000033:anatomy & histology*; D003287:Contrast Media; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000295:instrumentation* / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010690:Phlebography / Q000379:methods; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed / Q000295:instrumentation* / Q000379:methods
D003287:Contrast Media