脑磁图功能区定位ppt课件.ppt

RIGHT 语言中枢定位 刺激方式: 文字识别刺激，错误时报错，以确定受试者的反应。 数据采集:Language采集模式 苹 果 电视机 Language recognition Imaging language function Language production SAM data (60-120 Hz) END * Dipole and SAM data superimposed on 3D MRI. The dipoles (dots) indicate the exact location of M1. The SAM images show spectral power changes in 60-120 Hz. The regions of the focal increase of spectral power show in red, and the peak values are indicated by yellow. Both the dipole and the SAM peak are localized in the hand area. * Sound motion was produced by custom designed software using DirectX * Waveform and contour maps of the auditory evoked magnetic fields following static sound (100) stimulation. One peak is clearly identifiable at 104 ms (M100). The contour map of the M100 indicates two dipoles. There is no clear response around 180 ms. The white area indicates outgoing magnetic fields and the gray area indicates ingoing magnetic fields. * Fig. 5. Magnetic resonance images in a typical case showing dipole positions corresponding to the M100 (dots). Note that the two dipoles are located in the superior temporal cortex. * Figure 5. Magnetic source imaging of a representative subject showing the brain area activated purely by mirror words at a latency of 298 ms (M5). Dipoles projected onto the brain surface indicate that M5 is generated from angular gyrus. 脑磁图功能区定位 吴婷 脑功能区定位 MEG可以在MRI影像上明确标记脑主要功能区，实现无创脑功能成像，同时与计算机导航系统融合，为手术入路方案制定，术中选择最佳入路而避免损伤脑功能区提供可靠依据 MEG的诱发磁场（evoked magnetic field）可以对皮质感觉区、视觉中枢、听觉中枢、嗅觉中枢、运动中枢及语言中枢等功能区进行定位。特别在颅内肿瘤或其他占位性病变引起解剖结构被挤压、推移使功能区发生移位后的确切部位，则可以避免术中损伤 不同性质的致痫灶位于重要功能区，MEG检查对手术入路和改变手术方式或治疗方案具有重要意义。 脑功能区定位 目前临床常用的MEG检查项目有 体感诱发磁场（Somatosensory evoked magnetie fields SEFs） 听觉诱发磁场(auditory evoked magnetic fields AEFs) 视觉诱发磁场(visual evoked magmetic fields VEFs) 运动诱发磁场(motor evoked magnetic fields ) 语言中枢定位(language evoked magnetic fields ) 体感诱发磁场(SEFs) 刺激方式: 持续3脉冲/秒刺激频率,刺激强度调整至拇指抽动,大约为1-15毫安. 刺激部位:正中神经 数据采集:SEF采集模式 听觉诱发磁场(A