功能和纤维成像在脑功能区胶质瘤中的应用

目的研究功能磁共振成像（fMRI）定位脑运动功能区和弥散张量纤维束示踪成像（diffusion tensor tractography,DTT）显示锥体束与肿瘤位置关系在脑胶质瘤行直接皮质电刺激手术的指导作用。方法对28例邻近或累及脑运动功能区的患者,术前在常规成像基础上,分别行双手握拳刺激策略的血氧水平依赖性功能磁共振成像（BOLD-fMRI）和弥散张量成像（DTI）,经工作站提供的BOLD．fMRI和DTI图像分析软件包获得脑运动功能区的激活图像、二维的部分各向异性伪彩图（fractional anisotropy,FA Color）和三维的白质纤维束示踪图。提供脑肿瘤与脑运动皮质区和运动传导束即锥体束的位置关系信息,制定手术方案。所有患者均行术中皮质直接电刺激定位运动区。术前、术后均行Karnofsky生活状态（KPS）评分,判断患者的状态。结果28例患者的fMRI和DTI获得良好的脑双手握拳运动功能区激活图像和锥体束纤维束走形图像,显示初级运动皮质区、运动前皮质区、辅助运动皮质区等手运动相关的脑功能区和运动传导束——锥体束与肿瘤的位置关系。在术前脑功能磁共振图像指导下,直接皮质电刺激快捷、准确定位初级运动皮质区,发现两者具有良好的一致性。术后患者KPS评分结果较术前提高。结论术前BOLD-fMRI和DTT可于活体、无创地描绘脑运动功能区和锥体束与肿瘤的功能解剖位置关系,优化手术方案,在唤醒麻醉下指导直接皮质电刺激定位运动区的手术,实现最大程度保护患者重要的功能,并最大程度地切除肿瘤。

Function magnetic resonance imaging and diffusion tensor tractography in patients with brain gliomas involving motor areas: clinical application and outcome

Objective To explore the role of preoperative blood oxygen level dependent(BOLD) functional magnetic resonance imaging(fMRI)and diffusion tensor tractography(DTT)to identify the relationship between motor cortical area,pyramidal tracts with brain gliomas in neurosurgical treatment of intraoperative electrical stimulation for gliomas involving motor areas at 3T.Methods Twenty-eight patients with brain gliomas involving motor areas were included.They underwent MRI examination,which included conventional T1WI,T2WI,BOLD-fMRI of bilateral hands movement paradigm and diffusion tenor imaging (DTI).The data of BOLD-fMRI and DTI were transferred to the workstation(Leonardo syngo 2003A, Siemens)and analyzed.Activation mapping of hands movement,fractional Anisotropy(FA)Color and three dimensional pyramidal tracts were produced.The relationship between motor cortical area,pyramidal tracts and brain gliomas was demonstrated,which was used to optimize-the pre-surgical planning.With guidance of the result of BOLD-fMRI and DTT,all patients received microsurgery under anaesthesia retaining consciousness using intraoperative motor functional brain mapping with the method of direct electrical stimulations.The brain lesions were removed as far as possible in the case of eloquent areas and sub-cortical important white matters preservation.The preoperative and postoperative KPS of all patients were operated to evaluate the state of patients.Results BOLD-fMRI,DTI were performed successfully in 28 patients.The relationship between the primary motor cortex,premoter area,supplementary motor area,pyramidal tracts and brain gliomas localized by preoperative fMRI and DTI.Under anaesthesia retaining consciousness,the primary motor area was monitored by the method of direct electrical stimulations with the guidance of preoperative BOLD-fMRI.There was good correlation between preoperative fMRI and intraoperative cortical stimulation.Furthermore,the preoperative mappings and DTT could make up for the un-monitored motor areas and pyramidal tracts during operative cortical stimulation.Comparing the preoperative KPS,the postoperative KPS was advanced.Conclusions BOLD-fMRI and DTT could non-invasively localize the relationship between brain motor cortex,pyramidal tracts and brain gliomas in vivo to optimize the surgical planning,guide the microsurgery under anaesthesia retaining consciousness using intraoperative motor functional brain mapping with the method of direct electrical stimulations and remove brain tumors as far as possible in the case of eloquent areas and sub-cortical important white matters preservation.