CT脑灌注成像结合CTA对脑梗死前期诊断的研究

目的 探讨64层容积CT脑灌注成像结合头颈部血管成像对脑梗死前期诊断的临床应用价值.资料与方法 对45例临床诊断为急性缺血性脑血管病而常规CT平扫未发现异常的病例进行脑灌注成像及头颈部血管成像检查.测量脑内感兴趣区(region of interest,ROI)的局部脑血流量(regional cerebral blood flow,rCBF)、局部脑血容量(regional cerebral blood volume,rCBV)、平均通过时间(mean transit time,MTT)、最大峰值时间(time to peak,TTP),并根据脑梗死前期的分期标准进行分析;对颈部及颅内病变血管按照北美症状性颈动脉内膜切除术试验(NASCET)标准计算狭窄率.结果 发现脑灌注异常42例,其中Ⅰ_1,期6例、Ⅰ_2期16例、Ⅱ_1期12例、Ⅱ_2期8例,其中7例同时有两个部位发现异常灌注区,分别处于Ⅰ_2期和Ⅱ_1期,3例未发现异常灌注区.患侧TTP、MTT与对侧镜像比较差异有统计学意义.45例行CTA检查,发现60支颈内动脉狭窄,24支椎动脉狭窄,27例颅内动脉血管不同程度狭窄,各期患者分布情况与相应供血动脉狭窄程度呈正相关.结论 64层容积CT脑灌注成像结合头颈部血管成像能清楚显示脑梗死前期的血流动力学异常及相应的血管狭窄程度,具有重要的临床应用价值.

A Study of CT Perfusion Imaging and CT Angiography in Cerebral Pre-infarction Period

Objective To investigate the clinical application value of 64-slice volume CT cerebral perfnsion images (CTPI) and CT angiography in stages of pre-infarction period. Materials and Methods Brain CT perfusion were performed in 45 patients with clinically diagnosed acute ischemic cerebral vascular disease and all cases showed normal with CT plain scan. Regional cerebral blood flow (rCBF),regional cerebral blood volume (rCBV),mean transit time (MTT) and time to peak (TTP) were measured within region of interest (ROI) and were analysed according to the stages of pre-infarction period. The stenosis ratio of all involved cervical and cerebral vessels were calculated according to North American Symptomatic Carotid Endarterectomy Trial (NASCET). Results Abnormal perfusion changes were found in 42 of 45 cases ,and there were 6 cases in stage Ⅰ_1. 16 cases in stage Ⅰ_2, 12 cases in stage Ⅱ_1 and 8 cases in stage Ⅱ_2. 7 cases were found abnormal perfusiou changes at two different regions, respectively in stage Ⅰ_2 and stage Ⅱ_1 The parameters TTP and MTT were statistical difference between ROI and opposite mirror image. Internal carotid artery stenosis were found 60 of 90 branches in 45 patients and vertebral artery stenosis were found 24 branches, encephalic artery stenosis were 27 cases. There was positive correlation between each stage of pre-infarction period and the stenosed degree of artery. Condu-sion CT perfusion imaging and CT angiography can clearly show the abnormal cerebral hemodynamic and vascular stenosis in pre-infarction period and have important clinical application value.