Abstract:

Objective　To investigate the clinical significance of regional leptomeningeal collateral (rLMC) score of susceptibility weighted angiography (SWAN) and cerebral blood flow (CBF) change of three dimensional pseudo continuous arterial spin labeling (3D-PCASL) in the prognosis assessment for patients with chronic middle cerebral artery occlusion (CMCAO). Methods　The clinical data of 35 patients with CMCAO admitted to Lianyungang TCM Hospital Affiliated to Nanjing University of Chinese Medicine from January 2017 to January 2022 were analyzed retrospectively, including 21 males and 14 females, aged (66.57±10.28) years. All patients underwent routine magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), SWAN, and 3D-pcASL examinations. The SWAN-rLMC score >12 points was defined as a poor collateral circulation (17 cases), and ≤12 points as a good collateral circulation (18 cases). Independent sample t test, Mann-Whitney U test, and χ² test were used to compare the data between the two groups, and the relationship between the good and bad SWAN-rLMC scores and CBF was analyzed. The area under the receiver operating characteristic curve (ROC-AUC) and the optimal cutoff value were used to evaluate the values of SWAN-rLMC score and CBF perfusion in determining the patients' prognosis. Results　Of the 35 patients with CMCAO, 15 were on the right side and 20 were on the left side. SWAN showed asymmetrical cortical venous sign (CVS) of posterior cerebral artery (PCA) in 26 cases, asymmetrical deep medullary vein (DMV) adjacent to lateral ventricle body in 21 cases, and both DMV and CVS dilation in 19 cases. Among the 18 cases with good SWAN-rLMC score, 12 cases had equal or high perfusion, while 16 cases had low perfusion in the 17 cases with poor SWAN-RLMC score. During follow-up, 17 patients had a poor prognosis [6 cases of cerebral infarction, 10 cases of transient ischemic attack (TIA), and 1 death]. According to the SWAN-rLMC score, the CBF of the affected side in the poor collateral circulation group [(31.76±10.72) ml·100 g^-1·min^-1] was lower than that in the good collateral circulation group [(48.82±18.63) ml·100 g^-1·min^-1], with a statistically significant difference (t=3.296, P<0.05). There was a statistically significant difference in the perfusion of the affected side between the good and poor collateral circulation groups (χ²=16.431, P<0.001). According to Mann-Whitney U test, the perfusion in the good collateral circulation group was better than that in the poor collateral circulation group, with a statistically significant difference (Z=3.660, P<0.001). The good prognosis rate of the good collateral circulation group with SWAN-rLMC score was higher than that of the poor collateral circulation group, and the good prognosis rate of the equal and high perfusion group was higher than that of the low perfusion group, with statistically significant differences (χ²=17.927 and 21.898, both P<0.001). The AUC values of SWAN-rLMC score and CBF perfusion in the assessment of poor prognosis were 0.858 and 0.882, respectively, with good recognition ability. The AUC value of the combination of SWAN-rLMC score and CBF perfusion was 0.954, with a statistically significant difference compared with AUC_SWAN-rLMC (Z=2.145, P<0.05). Conclusions　The improved SWAN-rLMC score and 3D-pcASL are imaging methods to evaluate collateral circulation, which can directly reflect the changes of cerebral oxygen metabolism, cerebral perfusion, and collateral circulation. The combined application of the two is conducive to providing individual quantitative basis for clinical prevention, treatment, and prognosis assessment, which has important clinical significance.

Key words:

Chronic middle cerebral artery occlusion, Regional leptomeningeal collateral score, Susceptibility weighted angiography, Three dimensional pseudo continuous arterial spin labeling, Prognosis

摘要：

目的　探讨磁敏感加权血管成像（SWAN）的区域性软脑膜侧支（rLMC）评分和三维伪连续动脉自旋标记（3D-pcASL）的脑血流量（CBF）变化对慢性大脑中动脉闭塞（CMCAO）患者预后评估的临床意义。方法　本回顾性分析以2017年1月至2022年1月南京中医药大学连云港附属医院收治的CMCAO患者35例为研究对象，其中男21例、女14例，年龄（66.57±10.28）岁，所有患者均行常规磁共振成像（MRI）、磁共振血管成像（MRA）、SWAN、3D-pcASL检查。将SWAN-rLMC评分>12分定义为侧支不良组（17例），≤12分为侧支良好组（18例），采用独立样本t检验、Mann-Whitney U检验、χ²检验对组间资料进行比较，分析SWAN-rLMC评分的良好组、不良组与CBF关系，采用受试者操作特征曲线（ROC）下的面积（AUC）和最佳截断值来评估SWAN-rLMC评分、CBF灌注判断患者预后的价值。结果　35例CMCAO患者右侧15例，左侧20例。SWAN显示大脑后动脉（PCA）的不对称皮质静脉征（CVS）26例，侧脑室体旁的不对称深髓质静脉（DMV）21例，均显示DMV和CVS扩张19例。SWAN-rLMC评分良好组18例中等、高灌注12例，不良组17例中等灌注1例。在随访中17例发生不良预后［6例脑梗死，10例短暂性缺血发作（TIA），1例死亡］。根据SWAN-rLMC评分的侧支不良组患侧CBF［（31.76±10.72）ml·100 g^-1·min^-1］低于侧支良好组［（48.82±18.63）ml·100 g^-1·min^-1］，差异有统计学意义（t=3.296，P<0.05）。侧支良好组与不良组患侧低灌注比较［33.3%（6/18）比94.1%（16/17）］，差异有统计学意义（χ²=16.431，P<0.001）。经Mann-Whitney U检验，侧支良好组的灌注优于不良组，差异有统计学意义（Z=3.660，P<0.001）。SWAN-rLMC评分侧支良好组的良好预后率高于侧支不良组，等及高灌注组的良好预后率高于低灌注组，差异均有统计学意义（χ²=17.927、21.898，均P<0.001）。SWAN-rLMC评分、CBF灌注判断不良预后的AUC值分别为0.858、0.882，均具有良好的识别能力。将SWAN-rLMC评分与CBF灌注相结合判断不良预后的AUC值为0.954，与AUC_SWAN-rLMC相比差异有统计学意义（Z=2.145，P<0.05）。结论　改良SWAN-rLMC评分和3D-pcASL是影像评估侧支循环方法，可以直观反映脑氧代谢、脑灌注和侧支循环变化，二者联合应用有利于更好为临床预防、治疗、预后评估提供个体定量依据，具有重要临床意义。

关键词:

慢性大脑中动脉闭塞, 区域性软脑膜侧支评分, 磁敏感加权血管成像, 三维伪连续动脉自旋标记, 预后