Huang Zhaodi, Xia Xiaona, Guan Shuai, Gong Gaolang, Luo Yishan, Shi Lin, Zhang Juntao, Meng Xiangshui
Department of Radiology, Qilu Hospital (Qingdao), Cheeloo College of Medicine, Shandong University, Qingdao, China.
State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.
Front Neurol. 2023 Aug 24;14:1206786. doi: 10.3389/fneur.2023.1206786. eCollection 2023.
Asymptomatic chronic cerebrovascular steno-occlusive disease is common, but the cognitive function and alterations in the brain's structural and functional profiles have not been well studied. This study aimed to reveal whether and how patients with asymptomatic middle cerebral artery (MCA) steno-occlusive disease and normal-appearing white matter differ in brain structural and functional profiles from normal controls and their correlations with cognitive function.
In all, 26 patients with asymptomatic MCA steno-occlusive disease and 22 healthy controls were compared for neurobehavioral assessments, brain volume, cortical thickness, fiber connectivity density (FiCD) value, and resting-state functional connectivity (FC) using multimodal MRI. We also investigated the associations between abnormal cortical thicknesses, FiCD values, and functional connectivities with the neurobehavioral assessments.
Patients performed worse on memory tasks (Auditory Verbal Learning Test-Huashan version) compared with healthy controls. Patients were divided into two groups: the right group (patients with right MCA steno-occlusive disease) and the left group (patients with left MCA steno-occlusive disease). The left group showed significant cortical thinning in the left superior parietal lobule, while the right group showed significant cortical thinning in the right superior parietal lobule and caudal portion of the right middle frontal gyrus. Increased FiCD values in the superior frontal region of the left hemisphere were observed in the left group. In addition, a set of interhemispheric and intrahemispheric FC showed a significant decrease or increase in both the left and right groups. Many functional connectivity profiles were positively correlated with cognitive scores. No correlation was found between cortical thickness, FiCD values, and cognitive scores.
Even if the patients with MCA steno-occlusive disease were asymptomatic and had normal-appearing white matter, their cognitive function and structural and functional profiles had changed, especially the FC. Alterations in FC may be an important mechanism underlying the neurodegenerative process in patients with asymptomatic MCA steno-occlusive disease before structural changes occur, so FC assessment may promote the detection of network alterations, which may be used as a biomarker of disease progression and therapeutic efficacy evaluation in these patients.
无症状性慢性脑血管狭窄闭塞性疾病很常见，但认知功能以及大脑结构和功能特征的改变尚未得到充分研究。本研究旨在揭示无症状性大脑中动脉（MCA）狭窄闭塞性疾病且白质外观正常的患者在大脑结构和功能特征方面与正常对照是否存在差异，以及它们与认知功能的相关性。
总共对26例无症状性MCA狭窄闭塞性疾病患者和22名健康对照进行了神经行为评估、脑容量、皮质厚度、纤维连接密度（FiCD）值和静息态功能连接（FC）的多模态磁共振成像比较。我们还研究了异常皮质厚度、FiCD值和功能连接与神经行为评估之间的关联。
与健康对照相比，患者在记忆任务（听觉言语学习测试 - 华山版）中的表现更差。患者被分为两组：右侧组（右侧MCA狭窄闭塞性疾病患者）和左侧组（左侧MCA狭窄闭塞性疾病患者）。左侧组在左侧顶上小叶显示出明显的皮质变薄，而右侧组在右侧顶上小叶和右侧额中回尾部显示出明显的皮质变薄。左侧组在左侧半球额上区观察到FiCD值增加。此外，一组半球间和半球内FC在左侧和右侧组中均显示出显著降低或增加。许多功能连接图谱与认知分数呈正相关。未发现皮质厚度、FiCD值与认知分数之间存在相关性。
即使MCA狭窄闭塞性疾病患者无症状且白质外观正常，他们的认知功能以及结构和功能特征也已发生改变，尤其是FC。FC的改变可能是无症状性MCA狭窄闭塞性疾病患者在结构变化发生之前神经退行性过程的重要机制，因此FC评估可能有助于检测网络改变，这可作为这些患者疾病进展和治疗疗效评估的生物标志物。
