18F-FDG PET脑显像对癫痫颅内电极放置部位的选择

目的 探讨18^F-FDG PET脑显像对癫痫颅内电极放置位置选择的价值。方法 52例难治性癫痫患者，其中男28例，女24例，年龄在7-38岁之间，平均22岁。所有患者脑MRI检查结果无异常。头皮EEG检查阴性23例，头皮EEG检查不确定癫痫部位的29例。采用SIEMENS ECAT47 PET扫描仪行18^F-FDG PET脑断层显像，在PET指导下经颅内电极定位后行癫痫灶切除。结果 52例癫痫18^F-FDG PET显像阳性患者中，发作期8例呈18^F-FDG摄取增高，发作间期44例呈18^F-FDG摄取减低。发作期18^F-FDG PET显像所提示的18^F-FDG摄取增高部位，颅内电极都可检测到癫痫波。18^F-FDG摄取减低44例患者，能记录癫痫波者39例，有效率为88.6%。5例不能检测癫痫波，无效率为11.4%。结论 18^F-FDG PET显像对癫痫颅内电极放置位置选择具有指导的价值，尤以发作期18^F-FDG PET显像明显。

Value of 18F-FDG PET in directing intracranial electrode placement to sites of epileptogenic focus

Objective To explore possibility of 18F-FDG PET imaging in directing intracranial electrode placement to sites of epileptogenic focus. Methods Fifty-two cases with intractable epilepsy were studied in 18F-FDG PET, all of them presented with normal MRI.Out of 52, 23 cases were negative and seizure focus in 29 could not be located in scalp electroencephalography (S-EEG). 18F-FDG PET cerebral imaging was done using SEIMENS ECAT47 scanner before operation. Intracranial electrode placement to sites of epileptogenic focus was chosen according to the results from 18F-FDG PET imaging,diagnostic accuracy in 18F-FDG PET imaging was determined according to the results from electrocorticography (ECoG) or intracranial electroencephalography (I-EEG). Results Epileptogenic foci presented with hypermetabolism in 8 cases during ictal state, hypometabolism in 44 interictally in 18F-FDG PET imaging.According to above results, epileptogenic focus could be found in 8 cases with ictal epilepsy and in 39 cases with interictal epilepsy by EcoG or I-EEG. However, epileptogenic focus could not be located in other 5 cases with interictal epilepsy. Diagnostic accuracy during ictal and interictal was 100%, 88.6%,respectively. Conclusion 18F-FDG PET imaging can be used to localize epileptogenic focus and direct intracranial electrode placement for recording ictal onsets according to metabolic change in sites of epileptogenic foci,especially ictally.