MRI脑灰质形态学分析在双重病理所致颞叶癫痫的应用

目的应用基于体素形态学(VBM)及基于表面形态学(SBM)分析,探讨双重病理所致颞叶癫痫磁共振成像(MRI)脑灰质结构变化。方法收集病理确诊为海马硬化(HS)合并局灶性皮质发育不良(FCD)的双重病理颞叶癫痫患者36例(左侧癫痫组20例、右侧癫痫组16例)及健康对照组30例行MRI T_1WI 3D BRAVO序列扫描,使用SPM及Freesurfer软件分别进行灰质体积及皮层厚度、皮层表面积分析,并采用独立样本t检验获得有统计学差异脑区。结果左、右侧癫痫组与对照组比较,病侧大部分颞叶(含海马)灰质体积减小,左侧癫痫组同侧丘脑及杏仁核灰质体积减小,其差异均有显著统计学意义(FDR校正,P0.001,K≥20体素)。癫痫组均出现部分颞叶及颞叶以外脑区皮层增厚,但左、右侧癫痫组异常脑区存在不同;同时癫痫组病变侧颞叶脑区皮层表面积减小,上述差异均具有统计学意义(未校正,P0.01,顶点数≥100)。结论HS合并FCD致颞叶癫痫病变侧颞叶(含海马)灰质体积广泛缩小为主要形态学特征,皮层表面积减小对病变定侧也有一定作用,单纯通过皮层增厚观察双重病理中FCD存在一定局限性。

MRI analysis of grey matter morphology in temporal lobe epilepsy caused by double pathology

Objective To analyze the gray matter (GM) of temporal lobe epilepsy (TLE) caused by double pathology using voxel-based morphometry and surface-based morphology methods.Methods The GM volume,cortical thickness,and cortical surface area on three-dimensional T1-weighted BRAVO sequence of 36 patients with left (20) and 16 right (16) TLE from hippocampal sclerosis (HS) and focal cortical dysplasia (FCD) were compared with that of 30 healthy subjects.Results In patients with TLE,GM volume was reduced in the ipsilateral epileptogenic temporal lobe gyrus including hippocampus.In addition,the left thalamus and amygdala volume was significantly decreased in left TLE (P＜0.001).The temporal and extra-temporal lobe cortical thickness was increased in some of the patients whereas the surface area of the ipsilateral temporal lobe was significantly reduced in TLE (P＜ 0.01).Conclusion In TLE caused by HS and FCD,the ipsilateral epileptogenic temporal lobe regions including hippocampus showed reduction in GM volume and cortical surface area.