缺血性脑卒中早期CT灌注成像的临床应用价值

目的 探讨缺血性脑卒中早期CT灌注成像（CTPI）的临床应用价值。方法 对45例发病24h内的缺血性脑卒中患者行头颅CT平扫与CTPI检查，计算缺血半暗带区及梗死区相对脑血流量（rCBF）、相对脑血容量（rCBV）、相对平均通过时间（rMTT）、相对峰值时间（rTTP）、相对峰值增强（rPE）的灌注参数及各个参数图异常灌注区面积。结果 CT平扫显示脑缺血性改变29例，其中为责任病灶21例，未见异常16例，未见责任病灶24例；对缺血性脑卒中早期诊断的敏感性为46．67％（21／45），特异性为72．41％（21／29）。CTPI显示灌注异常44例，均为责任病灶；灌注正常1例，后经头颅MRI证实为急性脑干梗死；对缺血性脑卒中早期诊断的敏感性为97．78％（44／45），特异性为100％（44／44）。CTPI较CT平扫对急性脑缺血性病灶更敏感（P〈0．01）。缺血半暗带区及梗死区各个灌注参数相对值之间呈正相关（均P〈0．01）。CTPI各个参数图异常灌注区面积之间呈正相关（均P〈0．01）。结论 CTPI能够早期诊断缺血性脑卒中；定量分析可区分中心梗死区、缺血半暗带区，有助于早期选择治疗方案。

Clinical applied value of computed tomography perfusion imaging in early stage of ischemic stroke

Objective To study the clinical applied value of computed tomography perfusion imaging(CTPI) in early stage of ischemic stroke.Methods Routine CT scan and CTPI were performed in 45 patients with early stage of ischemic stroke(onset within 24 hours).CTPI yields a set of perfusion related parameters of relatine cerebral blood flow(rCBF), cerebral blood volume(rCBV),mean transmit time(rMTT),time to peak(rTTP) and positive enhancement integral (rPE).Results In all 45 patients,21 cases showed concerning lesions in the 29 cases with cerebral ischemia results of routine CT scan.16 cases presented normal results. 24 cases were not showed concerning lesions.The sensitivity of diagnose for early stage of ischemic stroke by CT was 46.67% (21/45).The specificity was 72.41% (21/29).44 cases of CTPI with abnormal perfusion changes were all showed concerning lesions. Only one case of CTPI presented negative result,which was acute brainstem infarction confirmed by follow-up magnetic resonance imaging (MRI).The sensitivity of diagnose for early stage of ischemic stroke by CTPI was 97.78% (44/45).The specificity was 100% (44/44).There was significant difference between CTPI and routine CT scan(P<0.01).There were positive correlations among the all kinds of parameter values derived from CTPI and abnormal perfusion imagings in the area of ischemic penumbra and infarction (all P<0.01).Conclusions CTPI can be used in diagnosis of early stage of ischemic stroke.The quantitative evaluation can differentiate the core of infarction from ischemic penumbra.It can provide valuable information for doctor to choose suitable therapy project.