Perioperative Multimodal Evaluation and Surgical Tactics of Tumor-Related Epilepsy: 2-Dimensional Operative Video

Treatment of tumor-related epilepsy (TRE), especially for tumors near critical areas, requires surgeons to strike a balance between the epileptic benefit and functional outcome after surgery. Here, we present a case in which multimodal evaluation facilitated the achievement of such surgical balance. Informed patient consent was obtained. A 17-yr-old female presented with seizure attacks for 2 yr. Magnetic resonance imaging (MRI) revealed a right parietal mass lesion with hypointense signal on T1W imaging, hyperintense signal on T2W imaging, and homogeneous enhancement. Carbamazepine and valproate administration were unable to control the intermittent seizures. From the patient's history and imaging, the initial diagnosis was refractory TRE. Whether lesionectomy would achieve seizure freedom in this case was not certain. Therefore, dESI (dense array EEG source imaging) was used to localize the epileptic zone preoperatively; results showed that the epileptic zone was very close to the lesion in the primary motor cortex. Surgery was carried out under awake-anesthesia, with the aid of multimodal neuronavigation, intraoperative neurophysiological monitoring, and intraoperative MRI evaluation. A gross total lesion resection was achieved while preserving critical motor areas. Histopathology revealed ganglioglioma grade I diagnosis. No motor deficits following surgery were detected except slight increase of muscle tension in the right lower limb. At 6-mo follow-up, the patient was without any motor impairment or any other neurological deficits and completely seizure-free with the antiepileptic drug Carbamazepine 1200 mg/day.