Elaina Nor Safira, Malik Aamir Saeed, Shams Wafaa Khazaal, Badruddin Nasreen, Abdullah Jafri Malin, Reza Mohammad Faruque
Center for Intelligent Signal & Imaging Research (CISIR), Department of Electrical & Electronic Engineering, University Technology PETRONAS, Bandar Seri Iskandar, 31750, Tronoh, Perak, Malaysia.
Department of Neurosciences, Universiti Sains Malaysia (USM), 15160, Kubang Kerian Kelantan, Malaysia.
Clin Neuroradiol. 2018 Jun;28(2):267-281. doi: 10.1007/s00062-017-0557-0. Epub 2017 Jan 23.
To localize sensorimotor cortical activation in 10 patients with frontoparietal tumors using quantitative magnetoencephalography (MEG) with noise-normalized approaches.
Somatosensory evoked magnetic fields (SEFs) were elicited in 10 patients with somatosensory tumors and in 10 control participants using electrical stimulation of the median nerve via the right and left wrists. We localized the N20m component of the SEFs using dynamic statistical parametric mapping (dSPM) and standardized low-resolution brain electromagnetic tomography (sLORETA) combined with 3D magnetic resonance imaging (MRI). The obtained coordinates were compared between groups. Finally, we statistically evaluated the N20m parameters across hemispheres using non-parametric statistical tests.
The N20m sources were accurately localized to Brodmann area 3b in all members of the control group and in seven of the patients; however, the sources were shifted in three patients relative to locations outside the primary somatosensory cortex (SI). Compared with the affected (tumor) hemispheres in the patient group, N20m amplitudes and the strengths of the current sources were significantly lower in the unaffected hemispheres and in both hemispheres of the control group. These results were consistent for both dSPM and sLORETA approaches.
Tumors in the sensorimotor cortex lead to cortical functional reorganization and an increase in N20m amplitude and current-source strengths. Noise-normalized approaches for MEG analysis that are integrated with MRI show accurate and reliable localization of sensorimotor function.
使用噪声归一化方法的定量脑磁图（MEG）对10例额顶叶肿瘤患者的感觉运动皮层激活进行定位。
通过左右手腕对正中神经进行电刺激，在10例患有感觉肿瘤的患者和10名对照参与者中诱发体感诱发电磁场（SEF）。我们使用动态统计参数映射（dSPM）和标准化低分辨率脑电磁断层扫描（sLORETA）结合三维磁共振成像（MRI）对SEF的N20m成分进行定位。比较两组获得的坐标。最后，我们使用非参数统计检验对半球间的N20m参数进行统计学评估。
对照组所有成员和7例患者的N20m源准确地定位于布罗德曼3b区；然而，3例患者的源相对于初级体感皮层（SI）外的位置发生了偏移。与患者组的患侧（肿瘤）半球相比，未受影响半球和对照组的两个半球中N20m振幅和电流源强度均显著降低。dSPM和sLORETA方法的这些结果是一致的。
感觉运动皮层的肿瘤导致皮层功能重组以及N20m振幅和电流源强度增加。与MRI相结合的MEG分析的噪声归一化方法显示了感觉运动功能的准确可靠定位。
