Department of Neurosurgery, Charité-Universitaetsmedizin, Berlin, Germany.
Neurosurgery. 2009 Dec;65(6 Suppl):93-8; discussion 98-9. doi: 10.1227/01.NEU.0000348009.22750.59.
Transcranial magnetic stimulation (TMS) is a noninvasive method for analyzing cortical function. To utilize TMS for presurgical functional diagnostics, the magnetic impulse must be precisely targeted by stereotactically positioning the coil. The aim of this study was to evaluate the usefulness of TMS for operation planning when combined with a sensor-based electromagnetic navigation system (nTMS).
Preoperative functional mapping with nTMS was performed in 10 patients with rolandic tumors. Intraoperative mapping was performed with the "gold standard" of direct cortical stimulation. Stimulation was performed in the same predefined 5-mm raster for both modalities, and the results were compared.
In regard to the 5-mm mapping raster, the centers of gravity of nTMS and direct cortical stimulation were located at the same spot in 4 cases and at neighboring spots in the remaining 6 cases. The mean distance between the tumor and the nearest motor response ("safety margin") was 7.9 mm (range, 5-15 mm; standard deviation, 3.2 mm) for nTMS and 6.6 mm (range, 0-12 mm; standard deviation, 3.4 mm) for direct cortical stimulation.
nTMS allowed for reliable, precise application of the magnetic impulse, and the peritumoral somatotopy corresponded well between the 2 modalities in all 10 cases. nTMS is a promising method for preoperative functional mapping in motor cortex tumor surgery.
经颅磁刺激（TMS）是一种分析皮质功能的非侵入性方法。为了将 TMS 用于术前功能诊断，必须通过立体定位线圈精确靶向磁脉冲。本研究的目的是评估将 TMS 与基于传感器的电磁导航系统（nTMS）结合用于手术计划的有用性。
对 10 例 Rolandic 肿瘤患者进行 nTMS 术前功能映射。术中映射采用直接皮质刺激的“金标准”进行。两种模式均以相同的预定义 5-mm 栅格进行刺激，并对结果进行比较。
在 5-mm 映射栅格方面，nTMS 和直接皮质刺激的重心在 4 例中位于同一位置，在其余 6 例中位于相邻位置。nTMS 的肿瘤与最近运动反应之间的平均距离（“安全裕度”）为 7.9mm（范围为 5-15mm；标准差为 3.2mm），直接皮质刺激为 6.6mm（范围为 0-12mm；标准差为 3.4mm）。
nTMS 允许可靠、精确地应用磁脉冲，两种模式在所有 10 例中均具有良好的肿瘤周围体感定位对应关系。nTMS 是一种很有前途的运动皮层肿瘤手术术前功能映射方法。
