儿童注意缺陷多动障碍脑功能及功能连接研究

目的使用静息态功能磁共振成像技术研究注意缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)儿童的大脑局域自发功能活动及功能连接。材料与方法对10例ADHD患儿及10例正常对照组儿童进行全脑扫描,获取静息态功能图像。计算得到每个被试的低频振幅(amplitude of low-frequence fluctuation,ALFF)参数图,进行基于体素的组间比较。选取ALFF与对照组有显著差异的脑区做种子点,得到该区域与其他脑区之间的功能连接强度参数图,采用相同的方法比较两组被试之间的差别。结果与正常对照组相比,ADHD患儿在前扣带回、前额叶、尾状核等脑区存在显著的ALFF升高,提示自发功能活动更加活跃。与对照组相比,以前扣带为种子点,ADHD儿童在双侧丘脑、岛叶及后扣带区域功能连接显著升高;以右侧前额叶的脑区为种子点,ADHD的右侧中央前回和颞上回的功能连接下降;以尾状核为种子点,ADHD在双侧的额中回功能连接下降。结论 ADHD儿童局域脑区自发功能活动及其功能连接异常,揭示ADHD症状与认知注意网络的发育延迟或缺损有关。

A study of rest-stating functional magnetic resonance imaging in children with attention deficit hyperactivity disorder

Objective: To investigate the regional and network pattern of the dysfunctional brain in ADHD children using resting-state functional MRI. Materials and Methods: Resting-state functional brain MR images were acquired for 10 ADHD children and 10 matched healthy controls. Parametric maps of the amplitude of low frequency fluctuations (ALFF) were calculated and group comparison was performed using a voxel-based approach, then brain regions with differences in ALFF were extracted as seeds to calculate functional connectivity (FC) maps. Results: Compared with healthy controls, children with ADHD showed increased ALFF in bilateral anterior cingulate cortex (ACC), caudate and right mid and superior-frontal cortex. When using ACC as seed region, ADHD group showed FC increase in bilateral thalami, insula and posterior cingulate cortex; when the right frontal cluster was selected as seed, FC with the right precentral gyrus and superior temporal gyrus demonstrated reduced FC in ADHD; at last, when using caudate as seed region, bilateral mid-frontal regions showed FC decrease. Conclusion: We identified abnormalities in the regional spontaneous brain activities and inter-regional functional connectivity in ADHD, indicating its association with the developmental delay or deficits of cognitive and attention network.