Association of plaque compositions and stenosis patterns in carotid bifurcation using MR imaging

To investigate the relationship between plaque compositions and stenosis patterns in patients with atherosclerotic plaques at the carotid bifurcation using magnetic resonance (MR) imaging.

One hundred and four carotid arteries with stenosis over 50% from 75 symptomatic stroke patients (64 male and 11 female; mean age 58·2±13·3 years) were studied. Plaque compositions were analyzed by high-resolution MR imaging using a 3·0T MR with a surface coil. Stenosis patterns were classified into three types according to contrast-enhanced MR angiography images. Correlations of different components of plaques and stenosis patterns were analyzed.

One hundred and four carotid arteries were analyzed. Three stenosis patterns were identified. The prevalences of the three patterns are as follows: type I (total occlusion) at 27·9% (29/104), type II (local plaque with normal distant flow) at 56·7% (59/104), and type III (local plaque with impaired distant flow) at 15·4% (16/104). The contingency coefficients between stenosis pattern and stability, intraplaque hemorrhage (IPH), lipid necrotic core (LNC), and ulcer were 0·383 (P = 0·000), 0·290 (P = 0·008), 0·439 (P = 0·000), and 0·388 (P = 0·000), respectively. Multinomial analysis showed that compared with type III vessels, type I vessels were more likely to contain IPH (P = 0·019) and less likely to contain large LNC (P = 0·001); type II vessels had a greater possibility for containing IPH than type III vessels (P = 0·009); LNC was more likely to be found in type II than in type I vessels (P = 0·000). No significant difference was found in ulceration prevalence between type II and type III vessels (P = 0·058).

The current study demonstrated positive associations between stenosis patterns and plaque compositions.