Abstract: Objective　To explore the relationship between ischemic penumbra, collateral circulation, and prognosis in ischemic stroke patients by multimodal CT. Methods　A total of 120 patients with ischemic stroke treated in The Third People's Hospital of Hubei Province, Jianghan University were enrolled between December 2018 and December 2020. There were 68 males and 52 females, with an age of (62.96±4.23) years old. The multimodal CT examination was conducted to obtain perfusion parameters such as relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), relative mean transit time (rMTT), relative time to peak (rTTP), and permeability surface (PS). According to the collateral circulation grading system of American ASITN/SIR, the patients were divided into a good collateral circulation group (51 cases) and a poor collateral circulation group (69 cases). The perfusion parameters of core infarct area and ischemic penumbra and infarct range were compared between the two groups. After 6 months of follow-up, the prognosis [modified Rankin scale (mRS) score] was compared between the two groups. The hemorrhagic transformation (HT) was evaluated by CT perfusion (CTP). According to presence or absence of HT, the patients were divided into a HT group (41 cases) and a non-HT group (79 cases), and the perfusion parameters were compared between the two groups. Independent sample t test was used for the measurement data, and χ² test was used for the count data. Results　The rates of hypertension and diabetes mellitus in the poor collateral circulation group were higher than those in the good collateral circulation group (both P<0.05). The rCBV, rMTT, and rTTP of core infarct area in the good collateral circulation group were (1.57±0.44) ml/100 g, (2.61±0.73) s, and (1.15±0.32) s, respectively, which were higher than those in the poor collateral circulation group [(1.09±0.32) ml/100 g, (1.87±0.51) s, and (0.92±0.15) s] (all P<0.05); there was no statistically significant difference in the rCBF of core infarct area between the two groups (P>0.05). There were no statistically significant differences in the rCBV, rMTT, and rTTP of ischemic penumbra between the good collateral circulation group and the poor collateral circulation group (all P>0.05); the rCBF of ischemic penumbra in the good collateral circulation group was (0.81±0.42) ml/100 g·min^-1, which was higher than that in the poor collateral circulation group [(0.59±0.17) ml/100 g·min^-1] (P<0.05). The infarct range and mRS score of the good collateral circulation group were (5.98±1.47) ml and (1.64±0.35) points, respectively, which were lower than those of the poor collateral circulation group [(18.03±4.21) ml and (4.31±1.13) points] (both P<0.05). There were no statistically significant differences in the CBV and CBF of the affected side between the HT group and the non-HT group (both P>0.05); the MTT of the HT group was (3.25±0.87) s, lower than that of the non-HT group [(5.06±1.29) s], and the PS was (17.15±4.18) ml/min·100 g, significantly higher than that of the non-HT group [(2.03±0.54) ml/min·100 g] (both P<0.05). Conclusions　Multimodal CT examination can effectively evaluate the collateral circulation, ischemic penumbra, and HT in ischemic stroke patients. Establishing and promoting good collateral circulation can reduce the range of infarct lesions and improve the prognosis.

Key words: Multimodal CT examination, Ischemic stroke, Ischemic penumbra, Collateral circulation, Prognosis

摘要： 目的　探究多模式CT检查评价缺血性脑卒中患者缺血半暗带、侧支循环与预后的关系。方法　选择2018年12月至2020年12月来江汉大学附属湖北省第三人民医院就诊的缺血性脑卒中患者120例，男68例、女52例，年龄（62.96±4.23）岁。对患者进行多模式CT检查，处理数据得到相对脑血容量（rCBV）、相对脑血流量（rCBF）、相对平均通过时间（rMTT）和相对达峰时间（rTTP）、表面通透性（PS）等灌注参数。根据美国ASITN/SIR侧支循环分级系统将患者分为侧支循环良好组51例、侧支循环不良组69例，比较两组的梗死核心区、缺血半暗带区域的灌注参数以及梗死范围，随访6个月后，比较两组预后［改良Rankin量表（mRS）评分］。采用CT灌注成像（CT perfusion，CTP）评估出血性转化（HT）情况，依据是否发生HT将患者分为HT组（41例）及未发生HT组（79例），比较两组灌注参数。计量资料采用独立样本t检验，计数资料采用χ²检验。结果　侧支循环不良组的高血压、糖尿病患者比例高于侧支循环良好组（均P<0.05）。侧支循环良好组梗死核心区的rCBV、rMTT、rTTP水平分别为（1.57±0.44）ml/100 g、（2.61±0.73）s、（1.15±0.32）s，均高于侧支循环不良组的（1.09±0.32）ml/100 g、（1.87±0.51）s、（0.92±0.15）s（均P<0.05）；两组梗死核心区的rCBF水平比较差异无统计学意义（P>0.05）。侧支循环良好组与侧支循环不良组缺血半暗带的rCBV、rMTT、rTTP水平比较差异均无统计学意义（均P>0.05）；侧支循环良好组缺血半暗带的rCBF水平为（0.81±0.42）ml/100 g·min^-1，高于侧支循环不良组的（0.59±0.17）ml/100 g·min^-1（P<0.05）。侧支循环良好组的梗死范围、mRS评分分别为（5.98±1.47）ml、（1.64±0.35）分，均低于侧支循环不良组的（18.03±4.21）ml、（4.31±1.13）分（均P<0.05）。HT组与未发生HT组患侧的CBV、CBF水平比较差异均无统计学意义（均P>0.05），HT组的MTT水平为（3.25±0.87）s，低于未发生HT组的（5.06±1.29）s，PS水平为（17.15±4.18）ml/min·100 g，高于未发生HT组的（2.03±0.54）ml/min·100 g（均P<0.05）。结论　多模式CT检测能够对缺血性脑卒中患者的侧支循环、缺血半暗带情况及HT的发生进行有效评估，建立并促进良好的侧支循环能减少梗死病灶体积，改善预后。

关键词: 多模式CT检查, 缺血性脑卒中, 缺血半暗带, 侧支循环, 预后