Atherosclerosis of middle cerebral artery: evaluation with high-resolution MR imaging at 3T.
OBJECTIVE
Three-dimensional time-of-flight magnetic resonance angiography (3D TOF MRA) has been wildly used in the diagnosis of intracranial artery diseases, but it only shows the arterial lumen and does not delineate the vessel wall. The aim of this study was to assess whether high resolution cross sectional magnetic resonance imaging (HRMRI) could compensate the limitation of 3D TOF MRA in the atherosclerotic disease of middle cerebral artery (MCA).


METHODS
Fourty-eight suspected patients with atherosclerotic stenosis of MCA underwent 3D TOF MRA and HRMRI with a 3T scanner. The HRMRI was performed in 49 MCAs perpendicular to the M1 segment with T2-weighted imaging. Findings of HRMRI were compared with that of 3D MRA.


RESULTS
HRMRI displayed the artery wall clearly, and showed 37 abnormalities, including 20 plaques and 17 wall thickening. The inter-observer reproducibility was moderate for wall abnormalities with k=0.75 (95% CI 0.59-0.91), and excellent for plaques with k=0.91 (95% CI 0.80-1.03). 3D TOF MRA showed 34 stenoses at the M1 segment. Five normal MCAs on 3D TOF MRA had abnormal wall (3 plaques and 2 wall-thickening) on HRMRI. Two stenoses on 3D TOF MRA showed normal wall structure on HRMRI, indicating a possible negative remodeling phenomenon.


CONCLUSIONS
High-resolution MR imaging can clearly depict the wall structure of middle cerebral arteries. As a complementary method, HRMRI may compensate the limitation of 3D TOF MRA and help to detect atherosclerotic lesions not visualized by MRA.
Li
Ming-li
ML
Department of Radiology, Peking Union Medical College Hospital and Chinese Academy of Medical Science, Shuai Fu Yuan 1#, Dong Cheng District, Beijing 100730, China.
Xu
Wei-hai
WH
Song
Lan
L
Feng
Feng
F
You
Hui
H
Ni
Jun
J
Gao
Shan
S
Cui
Li-ying
LY
Jin
Zheng-yu
ZY
D000368:Aged; D002533:Cerebral Angiography / Q000379:methods*; D003251:Constriction, Pathologic; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology*; D002537:Intracranial Arteriosclerosis / Q000473:pathology*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000473:pathology*; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results