Chandra Poodipedi S, Salamon Noriko, Huang Jimmy, Wu Joyce Y, Koh Susan, Vinters Harry V, Mathern Gary W
Division of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
Epilepsia. 2006 Sep;47(9):1543-9. doi: 10.1111/j.1528-1167.2006.00627.x.
Patients with tuberous sclerosis complex (TSC) are potential surgical candidates if the epileptogenic region(s) can be accurately identified. This retrospective study determined whether FDG-PET/MRI coregistration and diffusion-tensor imaging (DTI) showed better accuracy in the localization of epileptogenic cortex than structural MRI in TSC patients.
FDG-PET/MRI coregistration and/or DTI for apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were utilized in 15 TSC patients. Presurgery scalp EEG and postsurgery seizure control identified epileptogenic tubers (n = 27) and these were compared with nonepileptogenic tubers (n = 204) for MRI tuber volume, volume of FDG-PET hypometabolism on MRI coregistration, DTI, ADC, and FA values.
Compared with nonepileptogenic tubers, epileptogenic regions had increased volume of FDG-PET hypometabolism (p < 0.0001), and increased ADC values in subtuber white matter (p < 0.0001). In contrast, the largest MRI identified tuber (p = 0.046) and decreased FA values (p = 0.58) were less accurate in identifying epileptogenic regions. Larger volumes of FDG-PET hypometabolism correlated positively with increased ADC values (p = 0.029), and localized to areas of cortical dysplasia adjacent to the tuber in four cases.
Larger volumes of FDG-PET hypometabolism relative to MRI tuber size and higher ADC values identified epileptogenic tubers and adjoining cortex containing cortical dysplasia in TSC patients with improved accuracy compared with largest tuber by MRI or lowest FA values. Used in conjunction with ictal scalp EEG and interictal magnetoencephalography, these newer neuroimaging techniques should improve the noninvasive evaluation of TSC patients with intractable epilepsy in distinguishing epileptogenic sites for surgical resection.
如果能准确识别致痫区域，结节性硬化症（TSC）患者是潜在的手术候选者。这项回顾性研究确定了在TSC患者中，氟代脱氧葡萄糖正电子发射断层扫描/磁共振成像（FDG-PET/MRI）融合及扩散张量成像（DTI）在致痫皮层定位方面是否比结构MRI具有更高的准确性。
对15例TSC患者采用了FDG-PET/MRI融合及/或DTI来测量表观扩散系数（ADC）和分数各向异性（FA）。术前头皮脑电图及术后癫痫控制情况确定了致痫结节（n = 27），并将这些致痫结节与非致痫结节（n = 204）在MRI结节体积、MRI融合时FDG-PET低代谢体积、DTI、ADC及FA值方面进行比较。
与非致痫结节相比，致痫区域的FDG-PET低代谢体积增加（p < 0.0001），结节下白质的ADC值增加（p < 0.0001）。相比之下，MRI识别出的最大结节（p = 0.046）及降低的FA值（p = 0.58）在识别致痫区域方面准确性较低。更大体积的FDG-PET低代谢与增加的ADC值呈正相关（p = 0.029），并且在4例患者中定位于结节附近的皮质发育异常区域。
相对于MRI结节大小而言，更大体积的FDG-PET低代谢及更高的ADC值可识别TSC患者的致痫结节及包含皮质发育异常的相邻皮层，与MRI最大结节或最低FA值相比准确性更高。与发作期头皮脑电图及发作间期脑磁图联合使用，这些更新的神经影像技术应能改善对患有难治性癫痫的TSC患者进行手术切除致痫部位的无创评估。
