Cerebral ganglioglioma with epilepsy: neuroimaging features and treatment

Gangliogliomas are an increasingly recognized cause of epilepsy in children. In this study the clinical, neuroimaging, and neurophysiological data of five patients with cerebral ganglioglioma and epilepsy are reviewed retrospectively. The average age of these patients was 4.4 years at onset and the average duration of seizures before diagnosis was 11 months. Tumors were located in the frontal (3), parietal (1), and occipital (1) lobes. While one cystic and four solid tumors showed various densities on CT and MRI, one frontal lesion was not demonstrated by CT scan but clearly shown by MRI. Scalp electroencephalography (EEG) showed neither localized nor epileptiform abnormalities in three patients, while the remaining two had these abnormalities. In one patient, invasive chronic electrocorticography (ECoG) recordings with subdural electrodes revealed an ictal onset zone located in the hand motor area. In all patients, intraoperative ECoG failed to reveal any epileptiform activities, and tumor removal alone was performed. For a mean of 3.4 years after surgery, all patients are alive and seizure-free, with stable imaging findings. Tumor resection may be the most important factor for optimal seizure control and prevention of tumor recurrence despite the fact that EEG and ECoG findings may conflict on tumor location.