Clinical study of electroencephalogram features，pathological changes and epilepsy on the cortex around supratentorial tumors

Abstract:

Objective：To explore the electroencephalogram（EEG） features and pathological changes of brain tissue with EEG abnor－malities in patients with supratentorial tumors complicated with secondary epilepsy. Methods：Totally 36 patients with nonfunctional area supratentorial tumors complicated with secondary epilepsy were enrolled. Tumor and epileptiform discharges resection under the electrocorticography（ECoG） monitoring were performed. The resected brain cortex with epileptic discharges was as defined as experi－mental group and normal dumb organization（parenthesis of tumor resection） without epileptic discharges under the microscope in the tumor surrounding or decompression brain tissue was defined as control group. Characteristics of ECoG wave in experimental group were analyzed and postoperative pathologic results in experimental group and control group were compared. Results：（1）Characteristics of ECoG wave in patients with supratentorial tumors：14 cases（38.89%） showed intermittent polyspikes，followed by continuous spike and generalized sharp wave rhythm.（2）Pathological features：21 cases（58.33%） in experimental group showed irreversible glioma cell and simple glial cell hyperplasia and only 7 out of 30 cases（23.33%） in control group found glial cell hyperplasia. Glioma or glial cell hyperplasia was significantly higher in experimental group than in control group（P<0.05）. （3）Pathological results and characteristics of ECoG wave in experimental group：in nonreversible group：continuous single spike was mainly seen（P<0.05）. Intermittent polyspikes and generalized high amplitude sharp wave rhythm can seen both in two groups（P >0.05）. Conclusions：ECoG wave manifests mostly as continuous single spike in patients with supratentorial tumors complicated with secondary epilepsy. Pathological features of brain tissues with ECoG abnormalities are glioma cells and glial cell hyperplasia. Cerebral cortex around the tumor with recurring single high amplitude spikes，clusters multi-spikes and spike-sharp-wave rhythm of discharge in ECoG should be actively treated.