Value of contrast-enhanced MR angiography with 3D time-resolved imaging of contrast kinetics in the diagnosis of carotid artery atherosclerotic stenosis

Objective:To study the value of contrast-enhanced MR angiography(CE-MRA) with 3D time-resolved imaging of contrast kinetics(3D TRICKS MRA) in the diagnosis of carotid atherosclerotic stenosis.Methods:43 cases with clinically suspected carotid atherosclerotic stenosis underwent 3D TRICKS MRA and 2D time-of-flight(TOF) MRA.31 of these 43 cases underwent digital subtract angiography(DSA) within a week.The percentage of stenosis was calculated with common carotid artery method(CC).Results:There were occlusion(n=2),severe stenosis(n=10),moderate stenosis(n=31),mild stenosis of carotid artery(n=25) and normal carotid artery(n=18).Comparing the findings of 3D TRICKS MRA and 2D TOF MRA with DSA,all of the positions of carotid artery stenosis were in agreement;but there were overestimation of the stenotic degree by 2D TOF MRA(n= 6),only one was overestimated by 3D TRICKS MRA.Taking the diagnosis of DSA as the standard,the sensitivity,specificity and accuracy for evaluating carotid atherosclerotic stenosis by 2D TOF MRA was 91.6%,85.7%,90.3% respectively(Kappa=0.737);by 3D TRICKS MRA was 97.9%,100%,98.4% respectively(Kappa=0.955),with significant statistical differences(P0.05).Conclusion:3D TRICKS MRA in the evaluation of carotid atherosclerosis stenosis was in excellent agreement with DSA(Kappa=0.955),which was obviously superior to that of 2D TOF MRA(Kappa=0.737)(P0.05).3D TRICKS MRA is the technique of choice in the screening,preoperative evaluation and postoperative follow-up of carotid atherosclerosis stenosis,and might be the substitution of DSA in the future.