Epileptic Activity Detection Of Focal Epilepsy By Combined EEG And Simultaneous Functional MRI & Clinical Study Of Dysembryoplastic Neuroepithelial Tumor

Partâ… Epileptic activity detection of focal epilepsy using combined EEG and simultaneous functional MRIObjectives:To study the brain activation arose from the interictal epiletiform discharges(IEDs) and to locate the epileptic foci in patients with refractory epilepsy using combined scalp electroencephalogram (EEG) and simultaneous functional MRI(fMRI).Material and methods:The EEG and fMRI data of 12 patients with refractory epilepsy,who were diagnosed according to the Classicification of 2001 International Anti-Epilepsy Association from March 2006 to December 2007,were acquired using the technique of simultaneous EEG-monitored functional MRI.The time points of IEDs were detected with EEG,and were set as the time parameters of event-related paradigm in the general-linear-mode functional MRI test.The spatial location and temporal character of blood oxygenation level-dependent(BOLD) activation of IEDs were analyzed.All the subjects were scanned repeatedly and the detected epileptic lesions were compared with pathological focus to confirm the consistency and efficacy of the technique of EEG-fMRI.Results:Twelve patients of refractory epilepsy were examined by 24-hour video EEG,and 2-3 times of seizures were observed during the procedure and focal abnormalities were detected.MRI revealed focal lesions in 11 patients and no changes in the other.The data of EEG and MRI quality of each subject was good after being post-processed.Eighteen valid data were obtained from 10 patients. According to clinical manifestation,EEG and MRI findings,8 patients underwent surgery,with 6 of epileptic lesion resection and 2 of corpus callosum section,and the other 2 patients were treated with medication.The patients were followed up for 0.5-1 year, showing 3 of remission,1 of effective,4 of improvement, according to Tan Qi Fu evaluation system for surgery;and in 2 patients treated with medication,seizure time was reduced in 1 patient and no changes in another.The activation detected by EEG-fMRI of 11 sessions in 6 patients with lesion resection was consistent with pathologically confirmed focus,6 sessions in 3 patients were close to the lesion,and 1 session showed extended activation after seizure continuing status.Stable activation in contralateral cerebellum of activated cerebrum were observed in all patients.There was robust activation in thalamus in 8 sessions, and deactivation was observed in the brain areas that represented default mode in 9 ssessions.Additionally,data of two patients were excluded because of failures in EEG performing due to vigorous head motion in one session of examination.Conclusion:The BOLD activation of IEDs can be used to locate the epileptic foci in patients with focal epilepsy.The ipsilateral thalamus and contralateral cerebellum play important roles in the discharge and spreading of epileptic activation.The IEDs make the default mode of brain suspended.The simultaneous EEG-fMRI combines the advantages of two methods of neuroimaging,can be as used an effective tool for clinical research on epilepsy. Partâ…¡Surgical Treatment of Dysembryoplastic Neuroepithelial Tumor under Electrophysiological SurveillanceObjectives:To explore the clinical features,EEG changes,pathological findings and managements of dysembryoplastic neuroepithelial tumor(DNT).Methods:The clinical manifestations,radiological appearances(CT and MRI),electrophysiological characteristics and pathological findings of 18 DNT cases,14 of which underwent operation from 2001 to 2007,were retrospectively analyzed.Results:All patients exhibited episodes of epilepsy,with various types associated with the location of the lesion.Out of 18 cases,the epileptogenic lesions in 14 patients were identified by electroencephalography(EEG) prior to the operation and 10 were further localized by EEG in operation.All lesions were surgically removed and routine pathological examination revealed specific type of gelation neuron,immunohistochemistry showed positive stain of S100 in involved neurons.All patients were followed up from 1 month to 6 years.The epilepsy seizure relapsed in 3 patients and the others were seizure free after the operation.The tumor did not relapse in any patients during the follow-up.Conclusions:DNT is a benign tumor,which can cause epileptic seizures related with abnormal developed cortex around the tumor.The tumor can be diagnosed by imaging,pathology and immunohistochemistry.Surgical resection is an ideal treatment for DNT and the epileptogenic lesions could be identified by EEG in operation.