不同发作类型内侧颞叶癫灰质改变的结构性磁共振成像研究

A structural MRI study: gray matter changes in mesial temporal lobe epilepsy patients with different seizure types

目的探讨不同发作类型内侧颞叶癫患者灰质体积变化及其与病程的相关性。方法共40例内侧颞叶癫患者[部分性发作20例(m TLE-PS组)和继发性全面性发作20例(m TLE-s GS组)]以及20例性别、年龄相匹配的正常对照者行头部T1-三维磁化准备快速梯度回波扫描,采用基于体素的形态学分析进行灰质结构分割,选取双侧额叶和丘脑作为兴趣区,比较3组受试者各脑区灰质体积,采用Spearman秩相关分析探讨内侧颞叶癫患者各脑区灰质体积与病程的相关性。结果 3组受试者双侧额上回、右侧额中回、右侧额内侧回、右侧角回、右侧颞中回、右侧海马、双侧丘脑和双侧小脑半球灰质体积差异有统计学意义(均P<0.01,FWE校正),与正常对照组相比,m TLE-PS组双侧额上回、小脑半球和右侧颞中回、海马、丘脑灰质体积减少(均P<0.01,FWE校正),m TLE-s GS组双侧额上回、丘脑、小脑半球和右侧角回、颞中回、海马灰质体积减少(均P<0.01,FWE校正);与m TLE-PS组相比,m TLE-s GS组双侧额上回、丘脑和右侧额内侧回、直回灰质体积减少(均P<0.01,FWE校正)。m TLE-s GS组患者左侧额上回(rs=-0.611,P=0.004)和右侧额中回(rs=-0.562,P=0.010)与病程呈负相关关系。结论不同发作类型内侧颞叶癫患者均存在双侧额叶、丘脑、小脑半球和右侧颞叶、海马灰质损伤,但损伤脑区有所不同,继发性全面性发作患者以双侧额叶和丘脑灰质体积减少为主,提示丘脑-皮质环路是内侧颞叶癫继发性全面性发作的重要结构基础。

Objective To observe gray matter volume changes and evaluate the relation between gray matter changes and duration of mesial temporal lobe epilepsy （mTLE） patients with different seizure types. Methods A total of 40 patients with mTLE, including 20 with partial seizures （mTLE-PS group） and 20 with secondarily generalized seizures （mTLE-sGS group）, and 20 sex- and age-matched healthy volunteers （control group） were recruited. T1-three-dimensional magnetization-prepared rapid gradient echo （T1-3D-MPRAGE） was scanned for voxel-based morphometry （VBM）. Bilateral frontal lobes and thalami were selected as regions of interest （ROIs） to compare gray matter volume of brain regions among 3 groups. Spearman rank correlation analysis was used to evaluate the correlation between gray matter volume of brain regions and duration. Results There were significant differences in gray matter volumes in bilateral superior frontal gyri, right middle frontal gyrus, right temproral gyrus, right hippocampus, bilateral thalami medial frontal gyrus, right angular gyrus, right middle and bilateral cerebellar hemispheres among 3 groups （P 〈 0.01, for all; FWE correction）. Compared with control group, gray matter volumes in bilateral superior frontal gyri, bilateral cerebellar hemispheres, right middle temproral gyrus, right hippocampus and right thalamus in mTLE-PS group were significantly decreased （P 〈 0.01, for all; FWE correction）. Compared with control group, gray matter volumes in bilateral superior frontal gyri, bilateral thalami, bilateral cerebellar hemispheres, right angular gyrus, right middle temporal gyrus and right hippocampus in mTLE- sGS group were significantly decreased （P 〈 0.01, for all; FWE correction）. Compared with mTLE-PS group, gray matter volumes in bilateral superior frontal gyri, bilateral thalami, right medial frontal gyrus and right gyrus rectus in mTLE-sGS group were significantly reduced （P 〈 0.01, for all; FWE correction）. Gray matter volumes in left superior frontal gyrus （rs=- 0.611, P = 0.004） and right middle frontal gyrus （rs =- 0.562, P = 0.010） were negatively correlated with duration in mTLE-sGS group. Conclusions mTLE patients with different seizure types have revealed multiple gray matter damages in bilateral frontal lobes, thalami and cerebellar hemispheres, and right temporal lobe and hippocampus, but there is a difference in the injured brain regions. Bilateral frontal lobes and thalami atrophy in secondarily generalized seizures of mTLE show that thalamocortical circuit plays an important role in secondarily generalied seizures of mTLE.