The value of carotid plaque magnetic resonance imaging and sequence optimization in preoperative assessment in elderly patients with carotid atherosclerosis / 中华老年医学杂志

ABSTRACT

Objective To study the value of carotid plaque magnetic resonance imaging (MRI) in pre-operation assessment in the elderly patients with carotid atherosclerosis and explore the possibility of minimizing the contrast weightings to gain sweeptime. Methods Totally 70 elderly patients with cerebral ischemia (average age of 68.8 years) underwent carotid MRI and digital subtraction angiography (DSA) due to the appearance of carotid plaque detected by ultrasound. Carotid plaque MRI was acquired with 3.0T MR scanner and 8 channel surface coil. The standard carotid plague MRI program included pre-and post-contrast T1 weighted imaging (T1WI), T2 weighted imaging, proton density weighted imaging and 3D time of flight MR angiography (3D TOF MRA). All these program were divided into two combinations the 5-sequence MRI (all the sequences) and 2-sequence MRI (T1WI and TOF MRA). Digital subtraction angiography (DSA) in coronal and lateral views of carotid artery was performed with GE Advantx LCN+. The software SPSS 13.0 was used to statistically analyze the difference between MRI and DSA, and that of two sequence combinations was used in the detection of luminal stenosis and fibrous cap (FC) rupture. Results Totally 135 arteries were analyzed while 3 arteries in one patient were excluded due to the poor quality image and stent placement. The degree of luminal stenosis were (38.3±31.0)% and (38.5±30.9)%, respectively, detected by the two MRI sequence-combination with no significant difference (t=2.447, P＞0.05) and was (35.1±31.8)% by DSA. There was a good concordance between MRI and DSA in luminal stenosis detection (Kappa value 0.773). No statistical difference was found between two MR sequence combinations in detecting FC rupture (both in 36 vessels). DSA detected FC rupture of 16 vessels, showing remarkably difference contrast to MRI(χ2=12.0, P＜0.01). Conclusions MRI can accurately detect the luminal stenosis and FC rupture. The short time scanning resulting from sequence optimization could make MRI much more suitable than DSA to do the pre-operation assessment for senile carotid atherosclerotic patients.