Abstract:

Objective To investigate the relationship between internal carotid artery angle (ICAA) and internal carotid artery (ICA) plaque morphology in patients with acute anterior circulation infarction using high resolution magnetic resonance imaging (HR-MRI). Methods Patients with acute anterior circulation infarction admitted to Beijing Tian Tan Hospital from November 2011 to June 2012 were enrolled in this study. All patients underwent HR-MRI examination to obtain ICAA and plaque morphology data. According to the median of ICAA, all patients were divided into ICAA ≥35° and <35° groups, and the amounts and characteristics of carotid atherosclerotic plaques between the two groups were compared. Multi-factor logistic regression analysis was performed to analyze the influencing factors of bilateral ICA plaques morphology. Results A total of 162 ICA images from 86 patients were included in the final analysis, with 78 vessels in ICAA ≥35° group and 84 vessels in ICAA <35° group. The detection rate of ICA plaques [92.3% (72/78) vs 56.0% (47/84), P <0.01] and vulnerable plaques [43.6% (34/78) vs 15.5% (13/84), P =0.03] in ICAA ≥35° group were both higher than that in ICAA <35° group, with statistical difference. The detection rate of lipid-rich necrotic core plaques [75.6% (59/78) vs 36.9% (31/84), P <0.01] and intraplaque hemorrhage [26.9% (21/78) vs 11.9% (10/84), P =0.02] were higher in ICAA ≥35° group than that in ICAA <35° group. Linear regression analysis showed that age was an independent risk factor of plaque calcification volume on the left side (B 0.35, 95%CI 0.21- 1.65, P =0.01) and intra-plaque hemorrhage volume on the right side (B 0.34, 95%CI 0.30-2.32, P =0.01), and the non-plane angle of ICAA was an independent risk factor of lipid-rich necrotic core volume in the plaques on the left side (B 0.37, 95%CI 1.23-7.33, P =0.01), and the non-plane angle of external carotid artery was a risk factor of plaque calcification volume on the right side (B 0.33, 95%CI 0.20-2.07, P =0.02). Conclusions With the increasing of ICA angle, the amount of plaques as well as vulnerable plaques increased. ICAA was associated with the components and amount of carotid plaques, while it was not an independent risk factor for carotid atherosclerosis.

Key words: Cerebral infarction; High resolution magnetic resonance imaging; Carotid artery angle

摘要：

目的 利用颈动脉高分辨率磁共振成像（high resolution MRI，HR-MRI）技术分析急性脑梗死患者颈 内动脉角（internal carotid artery angle，ICAA）与动脉粥样硬化斑块形态学特点，探讨ICAA与动脉粥样 硬化斑块形态的关系。 方法 入组2011年11月-2012年6月的急性颈内动脉系统脑梗死患者，行颈动脉HR-MRI 检查，获得每 例患者左右侧ICAA及动脉粥样硬化斑块形态资料。根据ICAA大小的中位数将颈动脉分为ICAA≥35°组 和ICAA＜35°组，比较两组血管颈动脉粥样硬化斑块发生率和斑块特点。分别以左右侧颈动脉粥样 硬化各斑块成分总量为因变量，对其可能的影响因素进行多因素回归分析。 结果 共有86例患者的162支颈动脉图像纳入最终分析，其中ICAA≥35°组78支，ICAA＜35°组84支， ICAA≥35°组动脉粥样硬化斑块检出率[72支（92.3%）vs 47支（56.0%），P＜0.01]及易损斑块检出率 [34支（43.6%）vs 13支（15.5%），P =0.03）]均较ICAA＜35°组高，差异有统计学意义。ICAA≥35°组动 脉粥样硬化斑块中富含脂质坏死核心[59支（75.6%）vs 31支（36.9%），P <0.01）]及斑块内出血[（21 支（26.9%）vs 10支（11.9%），P =0.02）]的检出率高。回归分析显示，年龄是左侧颈动脉粥样硬化斑块 钙化成分总量（B 0.35，95%CI 0.21～1.65，P =0.01）及右侧颈动脉粥样硬化斑块斑块内出血成分总量 （B 0.34，95%CI 0.30～2.32，P =0.01）的危险因素，ICAA非平面角（B 0.37，95%CI 1.23～7.33，P =0.01） 是左侧颈动脉粥样硬化斑块富含脂质坏死核心成分总量的危险因素，颈外动脉非平面角（B 0.33， 95%CI 0.20～2.07，P =0.02）是右侧颈动脉粥样硬化斑块钙化成分总量的危险因素。 结论 随着ICAA角度增大，动脉粥样硬化斑块的检出率呈上升趋势，ICAA大者易损动脉粥样硬化斑 块的检出率也高。ICAA对动脉粥样硬化斑块各成分的含量有影响。ICAA与颈动脉粥样硬化斑块的发 生有关，但并非是颈动脉粥样硬化发生的独立危险因素。

关键词: 脑梗死; 高分辨率磁共振成像; 颈动脉角