Neggers S F W, Langerak T R, Schutter D J L G, Mandl R C W, Ramsey N F, Lemmens P J J, Postma A
Department of Psychonomics, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands.
Neuroimage. 2004 Apr;21(4):1805-17. doi: 10.1016/j.neuroimage.2003.12.006.
Transcranial Magnetic Stimulation (TMS) delivers short magnetic pulses that penetrate the skull unattenuated, disrupting neural processing in a noninvasive, reversible way. To disrupt specific neural processes, coil placement over the proper site is critical. Therefore, a neural navigator (NeNa) was developed. NeNa is a frameless stereotactic device using structural and functional magnetic resonance imaging (fMRI) data to guide TMS coil placement. To coregister the participant's head to his MRI, 3D cursors are moved to anatomical landmarks on a skin rendering of the participants MRI on a screen, and measured at the head with a position measurement device. A method is proposed to calculate a rigid body transformation that can coregister both sets of coordinates under realistic noise conditions. After coregistration, NeNa visualizes in real time where the device is located with respect to the head, brain structures, and activated areas, enabling precise placement of the TMS coil over a predefined target region. NeNa was validated by stimulating 5 x 5 positions around the 'motor hotspot' (thumb movement area), which was marked on the scalp guided by individual fMRI data, while recording motor-evoked potentials (MEPs) from the abductor pollicis brevis (APB). The distance between the center of gravity (CoG) of MEP responses and the location marked on the scalp overlying maximum fMRI activation was on average less then 5 mm. The present results demonstrate that NeNa is a reliable method for image-guided TMS coil placement.
经颅磁刺激（TMS）会传递短磁脉冲，这些脉冲能毫无衰减地穿透颅骨，以非侵入性、可逆的方式干扰神经处理过程。为了干扰特定的神经过程，将线圈放置在合适的部位至关重要。因此，开发了一种神经导航仪（NeNa）。NeNa是一种无框架立体定向设备，它利用结构和功能磁共振成像（fMRI）数据来指导TMS线圈的放置。为了将参与者的头部与他的MRI进行配准，将3D光标移动到屏幕上参与者MRI皮肤渲染图上的解剖标志点，并使用位置测量设备在头部进行测量。提出了一种方法来计算刚体变换，该变换可以在实际噪声条件下对两组坐标进行配准。配准后，NeNa会实时显示设备相对于头部、脑结构和激活区域的位置，从而能够将TMS线圈精确放置在预定义的目标区域上。通过在由个体fMRI数据引导的头皮上标记的“运动热点”（拇指运动区域）周围刺激5×5个位置，同时记录拇短展肌（APB）的运动诱发电位（MEP），对NeNa进行了验证。MEP反应重心（CoG）与头皮上覆盖最大fMRI激活区域的标记位置之间的平均距离小于5毫米。目前的结果表明，NeNa是一种用于图像引导TMS线圈放置的可靠方法。
