摘要： 目的 探讨脑白质高信号（WMH）患者脑灌注改变与认知功能障碍的相关性。方法 纳入2018年10月至2020年10月安徽医科大学第一附属医院收治的80例脑白质高信号患者以及37例性别、年龄、受教育程度相匹配的对照者，前者根据Fazekas总评分分为轻度WMH组（33例，评分1~2）和中至重度WMH组（47例，评分3~6）。采用蒙特利尔认知评价量表（MoCA）评估整体认知功能，中文听觉词汇学习测验（CAVLT）评估记忆力，符号数字转换测验（SDMT）评估注意力，数字颜色连线测验（CTT）评估执行功能，以及Boston命名测验（BNT）修订版评估语言功能；采用三维伪连续动脉自旋标记（3D-pCASL）测定脑血流量；采用Pearson相关分析和偏相关分析探讨差异脑区脑血流量与认知功能障碍的相关性。结果 （1）3组受试者MoCA评分（F=3.433，P=0.036），CAVLT学习（F=4.123，P=0.019）、即刻回忆（F=7.929，P=0.001）、延迟回忆（F=6.738，P=0.002）和再认（F=5.762，P=0.004），SDMT正确数（F=5.136，P=0.008），CTT-A完成时间（F=7.155，P=0.001）和BNT正确数（F=4.329，P=0.032）差异均有统计学意义，其中，中至重度WMH组MoCA评分（t=2.525，P=0.013），CAVLT学习（t=2.683，P=0.009）、即刻回忆（t=3.593，P=0.004）、延迟回忆（t=3.497，P=0.001）和再认（t=3.264，P=0.002），SDMT（t=3.170，P=0.002）和BNT（t=2.584，P=0.011）正确数低于对照组，CAVLT学习（t=2.025，P=0.046）、即刻回忆（t=3.033，P=0.003）、延迟回忆（t=2.458，P=0.016）和再认（t=2.181，P=0.032）亦低于轻度WMH组，CTT-A完成时间高于对照组（t=-3.668，P=0.000）；轻度WMH组仅CTT-A完成时间高于对照组（t=-2.697，P=0.008）。（2）3组受试者右侧壳核、左侧壳核和右侧中扣带回脑血流量差异有统计学意义［均体素水平P < 0.001、团块水平P < 0.05，高斯随机场（GRF）校正］，中至重度WMH组右侧壳核（t=5.039，P=0.000；t=3.672，P=0.000），左侧壳核（t=5.808，P=0.000；t=2.665，P=0.009）和右侧中扣带回（t=5.038，P=0.000；t=3.319，P=0.001）脑血流量均高于对照组和轻度WMH组，轻度WMH组仅右侧中扣带回脑血流量高于对照组（t=1.476，P=0.006）。（3）相关分析显示，轻度WMH组右侧壳核脑血流量与SDMT正确数呈正相关（r=0.478，P=0.028）、与CTT-A完成时间呈负相关（r=-0.483，P=0.026），左侧壳核脑血流量与MoCA评分呈正相关（r=0.451，P=0.040）、与CTT-A完成时间呈负相关（r=-0.502，P=0.020），右侧中扣带回脑血流量与MoCA评分呈正相关（r=0.446，P=0.043）；中至重度WMH组仅右侧壳核脑血流量与CAVLT再认呈正相关（r=0.343，P=0.043）。结论 脑灌注改变可能是脑白质高信号的神经病理学机制，且与认知功能障碍有关。

关键词: 大脑小血管疾病, 血液灌注, 认知障碍, 磁共振成像

Abstract: Objective To explore the relationship between alteration of cerebral blood flow (CBF) and cognitive impairment in patients with white matter hyperintensity (WMH). Methods Eighty patients with WMH and 37 controls matching sex, age and education were enrolled. Patients with WMH were divided into mild WMH group (n=33, Fazekas score 1-2) and moderate-severe WMH group (n=47, Fazekas score 3-6). Montreal Cognitive Assessment (MoCA), Chinese Auditory Verbal Learning Test (CAVLT), Symbol Digit Modalities Test (SDMT), Color Trail Test (CTT) and Boston Naming Test (BNT) were respectively used to assess overall cognitive function, memory, attention, executive function and language. The 3D-pseudo-continuous arterial spin labeling (3D-pCASL) was used to assess CBF. The relationship between CBF and cognitive function was estimated by Pearson correlation and partial correlation analyses. Results 1) MoCA (F=3.433, P=0.036), CAVLT-study (F=4.123, P=0.019), CAVLT-immediate (F=7.929, P=0.001), CAVLT-delay (F=6.738, P=0.002), CAVLT-recognition (F=5.762, P=0.004), SDMT (F=5.136, P=0.008), CTT-A (F=7.155, P=0.001) and BNT (F=4.329, P=0.032) were statistically significant among 3 groups. The moderate-severe WMH group was less than control group in MoCA (t=2.525, P=0.013), CAVLT-study (t=2.683, P=0.009), CAVLT-immediate (t=3.593, P=0.004), CAVLT-delay (t=3.497, P=0.001), CAVLT-recognition (t=3.264, P=0.002), SDMT (t=3.170, P=0.002), BNT (t=2.584, P=0.011) as well as less than the mild WMH group in CAVLT-study (t=2.025, P=0.046), CAVLT-immediate (t=3.033, P=0.003), CAVLT-delay (t=2.458, P=0.016) and CAVLT-recognition (t=2.181, P=0.032), while more than control group in CTT-A (t=-3.668, P=0.000). The mild WMH group was more than control group in CTT-A (t=-2.697, P=0.008). 2) The CBF of right putamen, left putamen and right median cingulate were statistically significant among 3 groups[Gaussian random field (GRF) corrected, cluster P < 0.05, voxel P < 0.001]. Compared to control group and the mild WMH group, the CBF of the right putamen (t=5.039, P=0.000; t=3.672, P=0.000), the left putamen (t=5.808, P=0.000; t=2.665, P=0.009) and right median cingulate (t=5.038, P=0.000; t=3.319, P=0.001) were more in the moderate-severe WMH group. Compared to the control group, the CBF of the right median cingulate was higher in the mild WMH group (t=1.476, P=0.006). 3) The correlation analysis showed that in the mild WMH group, the CBF of the right putamen was positively correlated with SDMT (r=0.478, P=0.028), and negatively correlated with CTT-A (r=-0.483, P=0.026), the CBF of left putamen was positively correlated with MoCA (r=0.451, P=0.040), and negatively correlated with CTT-A (r=-0.502, P=0.020), the CBF of right median cingulate was positively correlated with MoCA (r=0.446, P=0.043); in the moderate-severe WMH group, the CBF of the right putamen was positively correlated with CAVLT-recognition (r=0.343, P=0.043). Conclusions The alteration of CBF in the brain may be a possible neuropathological mechanism of WMH and relate to cognitive impairment in WMH.

Key words: Cerebral small vessel diseases, Hemoperfusion, Cognition disorders, Magnetic resonance imaging