[A case of hemimegalencephaly: ictal EEG and SPECT].

A case of 1-month-old female infant with hemimegalencephaly was reported. This disorder is a rare malformation characterized by congenital hypertrophy of one hemisphere and ipsilateral ventriculomegaly. Clinical signs of the patient included a left sided macrocephaly, intractable seizures and delayed development. Ictal single photon emission computed tomography (SPECT) on the 49th day using 99mTc-HMPAO showed hyperperfusion in the left occipital and frontal lobes, when ictal EEG showed a sharp wave-burst appearing continuously in the left occipital lobe that spread to the left frontal lobe. Interictal SPECT on the 48th day demonstrated and increased tracer accumulation in the left hemisphere, especially in the left frontal lobe. In this case, the megalencephalic hemisphere might have an important role for epileptogenesis and its spread according to the ictal SPECT findings.