Liu Guangyao, Li Shan, Chen Nan, Zhao Ziyang, Guo Man, Liu Hong, Feng Jie, Zhang Dekui, Yao Zhijun, Hu Bin
Department of Magnetic Resonance, Lanzhou University Second Hospital, Lanzhou, China.
Gansu Provincial Key Laboratory of Wearable Computing, School of Information Science and Engineering, Lanzhou University, Lanzhou, China.
J Neurogastroenterol Motil. 2021 Jul 30;27(3):426-435. doi: 10.5056/jnm20134.
BACKGROUND/AIMS: Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disease characterized by recurrent abdominal pain and bowel dysfunction. However, the majority of previous neuroimaging studies focus on brain structure and connections but seldom on the inter-hemispheric connectivity or structural asymmetry. This study uses multi-modal imaging to investigate the abnormal changes across the 2 cerebral hemispheres in patients with IBS.
Structural MRI, resting-state functional MRI, and diffusion tensor imaging were acquired from 34 patients with IBS and 33 healthy controls. The voxel-mirrored homotopic connectivity, fractional anisotropy, fiber length, fiber number, and asymmetry index were calculated and assessed for group differences. In addition, we assessed their relevance for the severity of IBS.
Compared with healthy controls, the inter-hemispheric functional connectivity of patients with IBS showed higher levels in bilateral superior occipital gyrus, middle occipital gyrus, precuneus, posterior cingulate gyrus, and angular gyrus, but lower in supplementary motor area. The statistical results showed no significant difference in inter-hemispheric anatomical connections and structural asymmetry, however negative correlations between inter-hemispheric connectivity and the severity of IBS were found in some regions with significant difference.
s The functional connections between cerebral hemispheres were more susceptible to IBS than anatomical connections, and brain structure is relatively stable. Besides, the brain areas affected by IBS were concentrated in default mode network and sensorimotor network.
背景/目的：肠易激综合征（IBS）是一种常见的功能性胃肠疾病，其特征为反复出现腹痛和肠道功能障碍。然而，以往大多数神经影像学研究聚焦于脑结构和连接，而很少关注半球间连接或结构不对称性。本研究采用多模态成像来探究IBS患者两侧大脑半球的异常变化。
对34例IBS患者和33名健康对照者进行结构磁共振成像（MRI）、静息态功能MRI及扩散张量成像检查。计算并评估体素镜像同伦连接性、分数各向异性、纤维长度、纤维数量及不对称指数的组间差异。此外，评估它们与IBS严重程度的相关性。
与健康对照者相比，IBS患者的半球间功能连接在双侧枕上回、枕中回、楔前叶、后扣带回及角回水平较高，而在辅助运动区较低。统计结果显示半球间解剖连接和结构不对称性无显著差异，然而在一些有显著差异的区域发现半球间连接与IBS严重程度呈负相关。
大脑半球间的功能连接比解剖连接更容易受到IBS影响，且脑结构相对稳定。此外，受IBS影响的脑区集中在默认模式网络和感觉运动网络。
