Coexistence of ganglioglioma and cortical dysplasia in a patient with intractable epilepsy--case report.

An 8-year-old girl presented with coexistence of ganglioglioma and cortical dysplasia manifesting as intractable epilepsy. Preoperative computed tomography demonstrated a small calcified lesion in the left frontal lobe which was not diagnosed as ganglioglioma. Magnetic resonance imaging also failed to demonstrate positive evidence of ganglioglioma or cortical dysplasia. A calcified tumor and the surrounding epileptogenic areas were resected under electrocorticography (ECoG) guidance. Histological examination revealed coexistence of ganglioglioma and cortical dysplasia. The patient became seizure-free after surgery. Resection of the ganglioglioma together with the adjacent epileptogenic area under intraoperative ECoG guidance is important to achieve a successful surgical result in patients with ganglioglioma.