颞叶癫痫脑灰质和白质减少及其与病程的相关分析

摘要

目的 利用优化的基于体素的形态测量学(VBM)测量颞叶癫痫患者的脑灰质和白质的变化,研究其与临床指标的相关性.方法 收集71例确诊单侧颞叶癫痫的患者及22例健康人进行常规MR扫描,并采集3D快速扰相梯度回波(FSPGR) T1加权像.对3D T1结构像进行配准、分割和平滑后,利用一种优化的VBM进行分析,计算分割后的脑灰质和白质的体积,并将颞叶癫痫患者组和健康对照组进行比较,以获知颞叶癫痫患者各脑区的灰质和白质的变化,并将局部及全部脑灰质和白质的变化分别与患者的起病年龄及癫痫发作病程进行相关分析.结果 与正常人相比,优化的VBM在癫痫起源的同侧脑区和对侧脑区均发现弥漫的脑灰质和白质体积下降(P＜0.05).双侧大脑各叶均出现局部灰质体积下降,以颞叶和额叶的局部灰质体积下降明显,而局部白质体积下降出现在双侧颞叶、顶叶和额叶,且扣带回出现局部白质下降.全脑的灰质体积和白质体积与癫痫病程呈负相关(P＜0.05).在癫痫发作早期,脑实质下降趋势明显,且随着病程的延长,脑白质下降比灰质明显.结论 癫痫患者有广泛的灰质和白质体积减少,在癫痫病程早期下降明显,脑白质较灰质的体积下降更明显.%Objective To measure the volumetric changes of gray and white matters in patients with temporal lobe epilepsy (TLE) using voxel-based morphometric study (VBM) and correlate the changes with clinical parameters.Methods A total of 71 TLE patients were enrolled in the study,and 22 healthy subjects served as normal controls.Routine brain MRI and 3D fast spoiled gradient echo (FSPGR) Tl-weighted images of all the subjects were acquired.The 3D structural images were co-registered,segmented and smoothed,and then the images were analyzed using the optimized VBM with preprocessed using Diffeomorphic Anatomical Registration using Exponentiated Lie algebra (DARTEL) algorithm.The global and local gray matter and white matter volume of each subject were calculated and compared between the TLE patients and normal controls.The potential correlations between the changes of the global and local gray and white matters in the TLE patients and the clinical parameters including the age at onset and the duration of epilepsy were explored.Results Compared to the normal controls,the TLE patients had diffuse volumetric reduction of gray and white matters in cerebrum both ipsilateral and contralateral to the seizure focus (P ＜ 0.05).Local gray matter reduction was found extensively in bilateral cerebral lobes,especially in the temporal and frontal lobes.Local white matter reduction was found in bilateral temporal,parietal and frontal lobes,in addition to the cingulate gyrus.The global gray matter volume (Global GMV) and the global white matter volume (Global WMV) were negatively correlated to the duration of epilepsy with the most significant change occurring in the first year of epilepsy.Global WMV dropped more quickly than Global GMV during the prolonged disease course.Conclusions TLE patients have diffuse gray matter and white matter reduction,particularly in the early stage of epilepsy.The reduction of the white matter is more obvious than the gray matter.