颈动脉支架置入术并脑栓塞MRI特点分析

Analysis of MRI Characteristics of Cerebral Embolism After Carotid Artery Stenting

目的分析颈动脉支架置入术(CAS)并发脑栓塞的MRI特点及相应的临床表现。方法前瞻性分析74例CAS术后并发脑栓塞MRI特点,按照新发脑栓塞的形态、大小、数量及分布等分类。根据脑栓塞的部位及血供特点,分为颈动脉供血区栓塞(手术同侧前循环栓塞)与非颈动脉供血区栓塞,包括手术对侧前循环及后循环新发栓塞,后者再分成枕叶及小脑新发栓塞灶。同时,依据DSA和脑超声多普勒观察记录非颈动脉供血区栓塞相应前、后交通动脉开放状况。采用独立样本t检验分析术前有无临床症状、有无新发梗死灶对术后新发栓塞灶个数有无影响。观察术后临床症状与新发脑栓塞数量间的对应关系。结果 74例中新发栓塞灶除2个为大的片状灶外,其余均为为小圆点状或小斑片状灶。39例(52. 7%)新发栓塞灶1～4个,28例(37. 8%) 5～8个,4例(5. 4%) 9～20个,3例(4. 1%)病灶呈片状或栓塞数量多于20个以上。同侧前循环新发栓塞63例(85. 1%),对侧前循环32例(43. 2%),其中21例前交通动脉开放;后循环37例(50%),其中9例发现相应后交通动脉开放。11例(14. 9%)无颈动脉供血区栓塞而直接引起非供血区的栓塞,包括对侧前循环5例,后循环枕叶2例,小脑8例。独立样本t检验显示术前有无临床症状、有无新发梗死灶与新发脑栓塞数量没有明确的相关性(P值均> 0. 05)。2例病灶呈片状或栓塞数量多于20个以上者均有明确神经系统症状和体征出现。结论 CAS术后新发脑栓塞以小病灶多、数量少且个体差异大、症状出现率低、病灶分布广甚至呈"跳跃式"分布为特点。大片状与大量小病灶(> 20)的栓塞常伴有神经系统症状和体征出现。

Objective Analysis of MRI features and clinical manifestations of cerebral embolism after Carotid Artery Stenting. Methods Prospective analysis of the MRI characteristics of 74 cases of cerebral embolism after CAS,according to the shape,size,quantity and distribution of the new cerebral embolism,and so on. According to the location and the blood supply of cerebral embolism,divided into embolization of ipsilateral carotid circulation and non-ipsilateral circulations( including contralateral carotid or vertebrobasilar circulations,the latter subdivided into the new lesion of occipital lobes and cerebellum). Moreover,according to DSA and Transcranial Doppler ultrasound,the anterior and posterior communicating arteries of the embolization of non-ipsilateral circulations were observed. According to the number of new cerebral embolism,the new brain embolism was divided into four groups : 1-4,5-8,9-20,> 20,quantitative analysis of the relationship between whether they have the clinical symptoms and between whether have the new infarcts before CAS,was done. The corresponding relationship between postoperative clinical symptoms and the number of new cerebral embolism was observed. Results New embolism lesions in the 74 cases in addition to 2 large flaky lesions remaining are small dots or small patchy lesions. Of the 39 cases( 52. 7%),there were 1-4 new embolism,28( 37. 8%) 5-8,4( 5. 4%) 9-20,and 3( 4. 1%)the lesions were flaky or thrombosis in more than 20. 63 cases( 85. 1%) of the new embolism of ipsilateral carotid circulation,contralateral anterior circulation in 32 cases( 43. 2%),21 cases of anterior communicating artery open;37 cases( 50%) of posterior circulation,and in 9 cases the corresponding posterior communicating artery was opened. In 11 cases( 14. 9%),there was no embolization of the ipsilateral carotid artery,which directly caused the embolism of the contralateral anterior circulation in 5,the occipital lobe in 2,and the cerebellum in 8 cases. Statistics show that the number of new cerebral thrombosis have no clear relevance with the symptoms and new infarcts showed before CAS. 3 cases of the lesions with flaky or thrombosis in more than 20 showed definite neurological signs and symptoms. Conclusion CAS cerebral Embolic lesions appearsmall,few in number,asymptomatic,and widely distributed features. The embolizationof Large and multiple small lesions( > 20) is often accompanied by neurological signs and symptoms.