Cerebral blood perfusion in febrile convulsions with 123-IMP SPECT

Twenty-five pediatric patients with febrile convulsions underwent single photon emission computed tomography (SPECT) with N-isopropyl-p-[I-123] iodoamphetamine. Nineteen patients (76%) had a localized, decreased blood flow on early images, 12 of whom had it in the temporal region. According to seizure type, the abnormality was seen in 85% (17/20) for complex type, in contrast to 40% (2/5) for simple type. This finding has implications for pathological similarities between epilepsy and febrile convulsion. Delayed imaging performed on 12 patients showed redistribution in 5 of 9 patients having a decreased blood flow on early images. In the other 3 patients having normal findings on early images, however, different findings were seen on delayed images - normal, increased or decreased blood flow. There was no correlation between SPECT and encephalographic findings. A localized, decreased blood flow on SPECT seemed to reflect the risk for developing epilepsy. A follow-up care for preventing epilepsy is mandatory when there are abnormal findings on SPECT. (N.K.)