症状性和无症状性颈内动脉狭窄的大脑中动脉微栓子信号监测

Microembolic signals of middle cerebral artery monitored in patients with symptomatic and asymptomatic internal carotid artery stenosis

目的观察症状性和无症状性颈内动脉狭窄的患者大脑中动脉微栓子信号(microembolic sig-nals,MES)阳性率及MES计数的变化,研究微栓子与临床症状和颈内动脉狭窄程度的关系。方法选取症状性颈内动脉狭窄患者26例,无症状性颈内动脉狭窄患者20例及正常对照组30例;症状性颈内动脉狭窄组又分为短暂性脑缺血发作(transient ischemic attack,TIA)组(12例)和脑梗死组(14例);症状性和无症状性颈内动脉狭窄的患者均行DSA或CTA检查,并对颈内动脉狭窄程度进行分级;所有颈内动脉狭窄的患者均对颈内动脉狭窄同侧的大脑中动脉进行MES监测,正常对照组则对双侧大脑中动脉进行MES监测。结果有症状和无症状颈内动脉狭窄组的MES阳性率高于正常对照组(P<0.01);有症状颈内动脉狭窄组MES阳性率较无症状组高(P<0.05);TIA组和脑梗死组比较,MES阳性率无显著性差异(P>0.05);症状性和无症状性颈内动脉狭窄患者,轻、中、重度狭窄三组的MES阳性率比较均有显著性差异(P<0.05);MES阳性患者MES计数与颈内动脉狭窄程度呈正相关(r=0.9155,P<0.01)。结论 MES多见在颈内动脉狭窄患者,特别是症状性颈内动脉狭窄的患者,是缺血性脑血管疾病发生的高危因素。

To observe the microembolic signals of middle cerebral artery 1,n patients wltla symptomatic and asymptomatic internal carotid artery stenosis, and to study the relations between the microembolic signals and clinical symptom, the degrees of internal carotid artery stenosis. Methods 26 patients with symptomatic internal carotid artery stenosis, 20 patients with asymptomatic internal carotid artery stenosis and 30 normal participants were selected. Patients with symptomatic internal carotid artery stenosis were divided into two groups, one group including 12 cases with transient ischemic attack, the other one with 14 patients with cerebral infarctiorL Patients with symptomatic and asymptomatic internal carotid artery stenosis were examined by digital subtraction angiography or computed tomography angiography. The degrees of internal carotid artery stenosis were graded. In all patients with internal carotid artery stenosis, microembolic signals of homolateral middle cerebral artery were monitored by transcranial Doppler sonography, and in the normal control, microembolic signals of hibateral middle cerebral artery were monitored. Results The positive rates of the microembolic signals in patients with symptomatic and asymptomatic internal carotid artery stenosis were higher than that in the normal control （P〈0. 01）. Compared with the patients with asymptomatic internal carotid artery stenosis, the positive rates of the microembolic signals in patients with symptomatic internal carotid artery stenosis were also higher（P〈0. 05）. The positive rate of the microembolic signals in patients with transient ischemic attack had no difference with that in patients with cerebral infarction（P〈0. 05）. The positive rates of the microembolic signals in patients with light internal carotid artery stenosis, middle internal carotid artery stenosis and severe carotid artery stenosis were significantly different（P^0. 05）. The number of the microembolic signals in patients with microembolic signals was positively correlated with the degrees of internal carotidartery stenosis （r= 0. 9155,P〈0. 01）. Conclusions The microembolic signals may be an important risk factor for ischemic cerebrovascular disease in patients with internal carotid artery stenosis, especially in symptomatic patients.