99mTc-HMPAO SPECT in epileptic disorders in childhood]

Single photon emission tomography (SPECT) using Tc-99m-d,1-hexamethylpropylenamine oxime (HMPAO) was performed in two children with epileptic disorders during both sleeping and waking diurnal stages. Immediate postictal and interictal SPECT scans were obtained for a child with partial epilepsy. They demonstrated an interictal decrease in the regional cerebral blood flow (rCBF) and a more remarkable immediately postictal decrease in rCBF. The focus was in the same region of the SPECT for both interictal and postictal spikes. Another patient was diagnosed as having continuous spike-waves during slow sleep without epileptic seizures. Although SPECT during wakefulness showed no asymmetry, SPECT during sleep revealed decreased rCBF at the same location as the predominant area of diffuse epileptic discharges. We conclude that HMPAO SPECT is useful in investigation of the etiological mechanisms of seizures and epileptic discharges in epileptic disorders in childhood.