SERIAL IMP-SPECT AND EEG STUDIES IN AN INFANT WITH HEMIMEGALENCEPHALY

An 8-month-old girl of hypomelanosis of Ito associated with hemimegale ncephaly had frequent seizures beginning 44 h after birth. The seizure s were secondarily generalized or unilateral initially, followed by in fantile spasms at about 1.5 months of age. Frequent partial seizures a ppeared at 4 months of age. [I-123]N-Isopropyl-p-iodoamphetamine (IMP) single photon emission computed tomography (SPECT) was performed seri ally during an interictal period at 1, 3 and 7 months of age. At 1 and 3 months, IMP-SPECT showed a marked increase of IMP uptake in the pat hological left hemisphere and electroencephalography (EEG) revealed le ft-sided dominant hypsarrhythmia. At 7 months of age, a reversal was s een, there being decreased uptake on SPECT in the pathological hemisph ere and abundant high amplitude background activity mingled with epile ptic discharges on EEG in the non-pathological hemisphere. These seria l changes of IMP uptake on SPECT seemed to reflect either changes in e pileptic activity or maturational changes in cerebral perfusion in hem imegalencephaly.