颞叶癫痫神经网络一体化PET/MR多模态显像研究

Extra-temporal cortical and/or subcortical hypometabolic regions showed by interictal FDG PET brain scan of patients with medial temporal lobe epilepsy were nonspecific. Thus there existed difficulties in refractory epilepsy epileptogenic localization and prognosis of surgical treatment. The aim of this study is to combine the interictal FDG PET, conventional MRI sequence,resting state fMRI and DTI provided by integrated PET/MR simultaneously to explore the neural network of temporal lobe epilepsy. FDG PET imaging is a highly sensitive molecular imaging technology, which reflects neuronal energy metabolism and synaptic function. Resting state BOLD-fMRI reflects cortical functional connectivity. DTI 3D nerve fiber tracking depicts white matter nerve fiber structure and its integrity. We put the ROI in cortical and subcortical hypometabolic regions to be served as“seed”to do the seed based analysis of cortical functional connectivity, and do 3D nerve fiber tracking as well. According to these parameters obtained from multimodal imaging techniques, we hope to make a in-depth knowledge of TLE neural networks and to identify the role of these hypometabolic focus in seizure discharge and spreading by comparing the preoperative with postoperative network. The result obtained from our study bring benefit to the patients by preoperative precise location of epileptogenic foci and helping to make surgical plan. To our knowledge, there was no reported study about epileptic network research with integrated PET/MR before. And there was no established way to use the hypometabolic regions in interictal FDG PET as“seed”to do seed based cortical functional connectivity and 3D white matter fiber tracking. The methods and experimental designs established in our study for combining application of multimodal imaging could be used in exploring mechanism of many other nervous system diseases and the functional and structural organization of the brain.

颞叶癫痫发作间期FDG PET脑显像所示颞叶外代谢减低区无特异性,在难治性癫痫的致痫灶定位和预测手术疗效时存在困难。本课题凭借先进的一体化PET/MR设备,将癫痫发作间期的 FDG PET脑显像、高分辨率脑结构成像(常规MRI序列)与高级MRI生理成像技术(静息态fMRI 及DTI)有机结合,将FDG PET产生的代谢减低区作为“种子”,用种子相关分析法进行静息态 fMRI的数据分析测定皮层功能联系,并进行DTI 3D白质纤维束示踪以反映白质纤维束结构及完整性,本课题利用多种结构功能参数对颞叶癫痫患者的神经网络进行综合研究,并结合对比手术前后神经网络的变化,希望术前能对颞叶外低代谢灶性质作出判断,作为预测手术疗效和帮助手术决策的指标。此课题研究结果直接解决临床问题。相关实验设计国内外未见报道。本课题研究中建立的多种成像技术联合应用方法可在神经系统疾病和脑功能研究中推广应用。

本项目围绕药物难治性癫痫颞叶癫痫患者术后癫痫复发风险分析这一核心目标开展研究工作，基于药物难治性颞叶癫痫患者[18F]FDG-PET及磁共振弥散成像数据，采取多参数分析影像数据，探索药物难治性颞叶癫痫患者的神经代谢功能和结构异常，与临床预后之间的关系。.项目执行过程中，我们入组有意愿接受手术治疗的难治性颞叶癫痫患者，通过分析不同脑区的标准化摄取值比（SUVr）和脑白质（WM）纤维网络特征，以确定除颞叶致痫灶外，大脑不同脑区是否存在功能和结构的显著异常，并进行综合SUVr和FA的多元参数分析，探索多元参数对癫痫患者致痫灶定侧效能及预测预后的价值。同时利用前期研究正常衰老患者脑结构连接网络与代谢网络连接间的紧密联系的数据分析方法，对颞叶癫痫患者进一步行个体化的术前多参数影像数据分析；及期望构建颞叶癫痫患者术前致痫灶定位及术后癫痫发作风险的分析预测模型。.项目相关成果在主流SCI杂志Neuroimage及Clinical Nuclear Medicine发表论文3篇。本项目从代谢功能显像与结构影像学角度，分析药物难治性颞叶癫痫患者的异常脑机制，为帮助完善该类患者的手术治疗前评估和预测手术效果，提高相关手术的成功率进行有益的探索。研究中建立的多种成像技术联合应用方法可在其他神经系统疾病和脑功能研究中推广应用。.