基于谷氨酸波谱对颞叶癫痫致痫灶定侧研究

Investigation on the lateralization of epileptogenic focus in temporal lobe epilepsy using glutamate spectroscopy

目的利用常规MRI-FLAIR序列及短TE(TE=30 ms)谷氨酸波谱对颞叶癫痫患者致痫灶进行定侧,并且通过与临床病理结果做对照,评价其在颞叶癫痫定侧诊断中的价值。方法采用Siemens Trio Tim 3.0 T MRI扫描仪,对29例单侧TLE患者及29例健康正常人行常规MRI扫描(包括T_1WI,T_2WI及FLAIR序列,FLAIR序列包括平行及垂直海马两个位置)及短TE(TE=30 ms)MRS检查。利用FLAIR序列对癫痫灶进行定侧,利用Siemens Syngovia工作站测量TLE组及正常组双侧海马Glu/Cr比值。利用ROC曲线找出谷氨酸波谱诊断的阈值并评价谷氨酸波谱的诊断效能。通过与临床病理做对照,比较使用FLAIR序列定侧、使用谷氨酸波谱定侧两种方法的诊断价值。结果颞叶癫痫患者的病理结果有28例表现为海马硬化,1例表现为皮层发育不良。FLAIR序列定侧诊断的灵敏度77.78%,特异度96.77%,准确度87.93%。谷氨酸波谱定侧诊断的灵敏度92.60%,特异度90.30%,准确度91.38%。结论颞叶癫痫患者病理上多为海马硬化,FLAIR序列及谷氨酸波谱在海马硬化引起的颞叶癫痫定侧中具有较好的临床诊断价值,其中谷氨酸波谱临床诊断效能较FLAIR序列稍高。

Objective The objective of this study was to evaluate the effectiveness of conventional MRIFLAIR sequence combined with short TE(TE=30 ms)glutamic acid spectrumonthe lateralization of temporal lobe epilepsy by comparingwith the clinicopathological results.Methods Routine MRI scans(T1WI,T2WI,and FLAIR sequences,T1WI and T2WI sequences including axial position and FLAIR sequence including parallel and vertical hippocampus positions)and short TE(TE=30 ms)MRS were performed on 29 patients with unilateral TLE and 29 healthy individuals on a Siemens Trio Tim 3.0 T MRI scanner.The FLAIR sequence was used for the lateralizaion of the epileptic focus.The Siemens Syngovia workstation was used to measure the Glu/Cr ratio in TLE group and control group.The ROC curve was used to identify the threshold value of the glutamate spectrum for diagnosis and to evaluate the diagnostic effectivenessof glutamic acid spectrum.The correlation between the Glu/Cr ratio of TLE group and the course and age of disease were analyzed.By comparing with clinical pathology,the diagnostic effectiveness of the three methods using FLAIR sequence,using glutamate spectrum were compared.Results The pathological results of patients with temporal lobe epilepsy showed28 cases with hippocampal sclerosis,1 case withcortical dysplasia.The sensitivity,specificity,and accuracy of FLAIR sequence for lateralization were 77.78﹪,96.77﹪and 87.93﹪.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of glutamic acid spectrum for identifying epileptic focus were 92.60﹪,90.30﹪and 91.38﹪.Conclusion The pathological results of patients with temporal lobe epilepsy were mostly hippocampal sclerosis.FLAIR sequence and glutamic acid spectrum have good clinical diagnostic effectivenessin the localization of temporal lobe epilepsy,and the clinical diagnostic effectivenessof glutamic acid spectrum is slightly betterthan that of FLAIR sequence.