CONTRAST-ENHANCED 3D MR DSA OF THE CAROTID-ARTERY BIFURCATION - PRELIMINARY-STUDY OF COMPARISON WITH UNENHANCED 2D AND 3D TIME-OF-FLIGHT MR-ANGIOGRAPHY
Ds. Willig et al., CONTRAST-ENHANCED 3D MR DSA OF THE CAROTID-ARTERY BIFURCATION - PRELIMINARY-STUDY OF COMPARISON WITH UNENHANCED 2D AND 3D TIME-OF-FLIGHT MR-ANGIOGRAPHY, Radiology, 208(2), 1998, pp. 447-451
PURPOSE: To compare the delineation of stenosis of the carotid artery
bifurcation on three-dimensional (3D) magnetic resonance (MR) digital
subtraction angiographic (DSA) images with that on two-dimensional (2D
) and 3D time-of-flight (TOF) MR angiographic images. MATERIALS AND ME
THODS: Twenty-six patients with 29 carotid artery bifurcations and sym
ptoms of cerebral ischemia underwent 3D MR DSA. A time-resolved series
was generated with 3D MR DSA after the bolus injection of gadodiamide
. The resolution for a carotid artery examination was 0.4 x 0.4 x 1.0
mm, with volumes reconstructed at 4.5-second intervals. The 3D MR DSA
images were compared with contemporaneously acquired unenhanced 2D and
3D TOF images. Two observers ranked the 2D and 3D TOF MR angiographic
and 3D MR DSA images according to the following: (a) stenosis delinea
tion, (b) internal carotid artery delineation, (c) intravascular signa
l intensity, and (d) diagnostic confidence. RESULTS: The mean ranking
for diagnostic confidence was 1.10 (1 = best technique, 3 = worst tech
nique) for 3D MR DSA. Compared with the pooled 2D TOF and 3D TOF ranks
, the 3D MR DSA rank was significantly better (P < .01). Similar level
s of statistical significance were found for the other criteria. CONCL
USIONS: Three-dimensional MR DSA improves the delineation of carotid a
rterial stenosis by virtually eliminating saturation effects and reduc
ing intravoxel dephasing. Surface morphology and nearly occluded vesse
ls (''string sign'') were easily identified. Confidence in identifying
carotid arterial occlusions was also very high with this technique.