Qiao Zichen, Yang Yingxue, Chen Yuanhong, Guo Linai, Xue Qing, Gao Lehong, Chen Jia, Cui Bixiao, Liu Jinghui, Yang Haoxun, Wang Xueyuan, Wang Yihe, Zhang Huaqiang, Xu Cuiping, Lin Yicong, Yu Tao, Wang Yuping, Piao Yueshan, Lu Jie, Ren Liankun
Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China.
Clinical Research Center of Epilepsy, Xuanwu Hospital, Capital Medical University, Beijing, China.
Epilepsia. 2025 Jul;66(7):2339-2352. doi: 10.1111/epi.18351. Epub 2025 Mar 8.
The identification of epileptic lesions is crucial for improving surgical outcomes. Nevertheless, substantial focal cortical dysplasia (FCD) may be invisible on magnetic resonance imaging (MRI). We aimed to characterize the expression pattern of 18-kDa translocator protein (TSPO) in FCD and to evaluate the effectiveness of this inflammation-reflective molecular imaging technique for detecting FCD.
Patients clinically diagnosed with FCD, based on clinical features, interictal electroencephalographic (EEG) findings, and MRI characteristics, underwent positron emission tomography (PET) imaging using F-DPA714 and F-fluorodeoxyglucose (FDG) tracers. TSPO-PET activation patterns were qualitatively evaluated. Semiquantitative analysis using the Highlight Index (HI) was further performed to investigate its correlation with clinical characteristics. For patients who underwent stereo-EEG (SEEG) monitoring, the site of high-level TSPO-PET activation was compared with the seizure onset zone identified by SEEG. For patients who underwent resection surgery, the relationship between TSPO-PET uptake and histopathological findings was studied.
Twenty-four patients were enrolled. Three groups were identified: MRI-positive with visible high-level TSPO-PET activation (six patients), MRI-negative with visible high-level TSPO-PET activation (thirteen patients), and MRI-positive with invisible low-level TSPO-PET activation (five patients). Regions of high-level TSPO-PET activation showed concordance with ictal discharges in five patients who underwent SEEG. Compared with FDG-PET, TSPO-PET exhibited a more prominent signal against the background (p = .0158). HI was correlated with seizure frequency (p = .0362) and the occurrence of focal to bilateral tonic-clonic seizures (p = .0294), and shorter interval between the TSPO-PET scan and the last seizure was associated with higher TSPO-PET HI (R = -.4323, p = .0349). Postoperative histopathological examination confirmed high-level TSPO-PET activation rates of 3/3 for FCD type IIb and 1/3 for FCD type IIa.
TSPO-PET activation patterns offer clinical significance for improving surgical outcomes by enhancing FCD detection during presurgical evaluation. Also, our observations offer new insights into the histopathological basis for increased TSPO uptake in humans.
识别癫痫病灶对于改善手术效果至关重要。然而，大量局灶性皮质发育不良（FCD）在磁共振成像（MRI）上可能不可见。我们旨在描述FCD中18 kDa转位蛋白（TSPO）的表达模式，并评估这种反映炎症的分子成像技术检测FCD的有效性。
基于临床特征、发作间期脑电图（EEG）结果和MRI特征，临床诊断为FCD的患者使用F-DPA714和F-氟脱氧葡萄糖（FDG）示踪剂进行正电子发射断层扫描（PET）成像。对TSPO-PET激活模式进行定性评估。进一步使用亮点指数（HI）进行半定量分析，以研究其与临床特征的相关性。对于接受立体脑电图（SEEG）监测的患者，将TSPO-PET高激活部位与SEEG确定的癫痫发作起始区进行比较。对于接受切除手术的患者，研究TSPO-PET摄取与组织病理学结果之间的关系。
纳入24例患者。分为三组：MRI阳性且TSPO-PET可见高激活（6例）、MRI阴性且TSPO-PET可见高激活（13例）、MRI阳性且TSPO-PET可见低激活（5例）。在接受SEEG的5例患者中，TSPO-PET高激活区域与发作期放电一致。与FDG-PET相比，TSPO-PET在背景下显示出更突出的信号（p = 0.0158）。HI与癫痫发作频率（p = 0.0362）和局灶性至双侧强直阵挛发作的发生（p = 0.0294）相关，TSPO-PET扫描与最后一次发作之间的间隔越短，TSPO-PET HI越高（R = -0.4323，p = 0.0349）。术后组织病理学检查证实IIb型FCD的TSPO-PET高激活率为3/3，IIa型FCD为1/3。
TSPO-PET激活模式通过在术前评估中增强FCD检测，为改善手术效果提供了临床意义。此外，我们的观察结果为人类TSPO摄取增加的组织病理学基础提供了新的见解。
