[A case of oligodendroglioma with temporal lobe epilepsy initially suspected as having paroxymal tachycardia].

A 4-year-old girl had repetitive attacks of chest pain, palpitation and loss of consciousness, which lasted for a few minutes and occurred several times a day. Interictal and ictal EEGs revealed that these episodes were complex partial seizures with autonomic symptoms originating from the right antero-temporal area. Brain MRI depicted a tumor in the right temporal lobe, the suspected etiology of the seizures. The tumor and its surrounding area were carefully resected using electrocorticogram. Pathologically, the tumor was diagnosed as an oligodendroglioma. MR spectrometry demonstrated a definite reduction of NAA/creatine ratio in the tumor. It is reported that a probability of developing seizures in cases of oligodendroglioma is about 80-90%. The occurrence rate of seizures in oligodendroglioma is much higher than that in other brain tumors. The cause of the epileptogenesis in oligodendroglioma might be due to the pathological tissue of satellitosis and secondary degeneration of neurons.