难治性癫痫患者脑功能网络小世界属性变化的静息态功能MRI

Alteration of cerebral small world network in refractory epilepsy patients： a resting-state functional magnetic resonance imaging

目的 利用图论的方法,探讨难治性癫痫患者脑功能网络小世界属性的变化情况.方法 收集2013年11月至2014年9月在安徽医科大学附属省立医院癫痫门诊收治的难治性癫痫患者20例,健康对照者20名;采集两组静息态功能磁共振数据,应用SPM8软件包进行数据预处理,通过脑功能网络构建得到脑网络的功能连接矩阵,再通过阈值的限制计算得到脑网络小世界属性,经双样本t检验比较难治性癫痫患者较健康对照组相关脑区参数的变化情况.结果 以连接矩阵稀疏度为阈值,在0.05 ～0.40范围内,难治性癫痫组和健康对照组均符合小世界属性,两组对象的γ值（代表脑网络局部信息处理能力）差异具有统计学意义（1.834±0.323比2.182 ±0.199,t=-2.795,P＜0.05）;λ值（代表脑网络整体信息处理能力）在整体上差异无统计学意义,但是通过对90个脑区的节点λ值的进行统计分析发现,难治性癫痫患者双侧丘脑（左3.093 ±3.224,右3.084±3.233）、双侧苍白球（左1.120±0.777,右1.234 ±0.880）及双侧海马（左0.930±0.269,右1.041±0.357）λ值明显高于健康对照组（0.970 ±0.500,t=2.413;0.965 ±4.891,t=2.405;0.679±0.075,t=2.253;0.662±0.073,t =2.333;0.695 ±0.101,t=2.808;0.615 ±0.036,t =4.251;均P＜0.05）.结论 难治性癫痫患者仍具有小世界网络属性,但其局部信息处理效率和部分脑区的功能已经受损.

Objective To explore the small world property of cerebral ＆quot;small world＆quot; network in refractory epilepsy patients by the method of graph theory.Methods Twenty patients with refractory epilepsy and 20 healthy controls with age,sex and education level matched in the Affiliated Anhui Provincial Hospital,Anhui Medical University,were recruited from November 2013 to September 2014,gathering the two groups＇ resting state functional MRI data,applying the SPM8 software package for data preprocessing and obtaining the cerebral network functional connection matrix through the cerebral network construction,then getting the small word network property through the calculation of the threshold limit,by the two-sample t test to compare the alteration of the refractory epilepsy patients in the related cerebral regions parameters with the healthy control group.Results Regarding the connection of the matrix sparsity as the threshold,in the range of 0.05 to 0.40,the refractory epilepsy patients and the healthy controls both were in line with the small world property.The γ values of the two groups had a statistically significant difference （1.834 ± 0.323 vs 2.182 ±0.199,t =-2.795,P 〈0.05）,while the λ value overall did not.Statistical analysis of the 90 cerebral regions of the λ showed that the λ values in the bilateral thalamus （left 3.093 ± 3.224,right 3.084 ± 3.233）,bilateral globus pallidus （left 1.120 ± 0.777,right 1.234 ± 0.880） and bilateral hippocampus （left 0.930 ± 0.269,right 1.041 ± 0.357）of the refractory epilepsy patients were significantly higher than those of the healthy controls （0.970 ± 0.500,t =2.413;0.965 ± 4.891,t =2.405;0.679 ±0.075,t =2.253;0.662 ± 0.073,t =2.333;0.695 ± 0.101,t =2.808;0.615 ± 0.036,t =4.251;all P 〈0.05）.Conclusions The refractory epilepsy patients still have the small world network property,but the local information processing efficiency and part of the brain regions＇ function have been damaged.