Negative or positive imaging: ganglioglioma in a boy with epilepsy.

Ganglioglioma is a rare primary tumour of the central nervous system, which characteristically contain both neuronal and glial neoplastic components mainly in children and adolescents. The most common clinical presentation is refractory epilepsy. The imaging findings of ganglioglioma are obvious and varied. However, ganglioglioma with normal neuroimaging is rare. We report a 12-year-old boy presented with intractable focal epilepsy with normal CT and almost negative MRI. The epileptogenic focus was found to be located in the left posterior superior temporal gyrus by comprehensive evaluation including PET-CT imaging and stereo electroencephalography monitoring. The epileptogenic focus was resected, and the histological examination of the surgical specimen confirmed ganglioglioma. He was seizure-free at last follow-up 14 months after surgery.