POSTICTAL SPECT IN EPILEPTIC VERSUS NONEPILEPTIC SEIZURES

Despite advances in video-electroencephalogram (EEG) technology, in ma ny patients distinguishing epileptic seizures from nonepileptic seizur es (NES) remains a challenge. Reliable methods to make this distinctio n are needed. In a pilot study, we performed postictal and interictal single photon emission computed tomography (SPECT) in 22 patients unde rgoing video-EEG monitoring who had altered responsiveness during an e pisode. Eleven had seizures, defined as episodes associated with EEG s eizure patterns or postictal prolactin (PRL) elevations greater than 1 .5 times the highest interictal baseline PRL; 11 had NES. Among the 11 seizures, postictal SPECT was abnormal in seven (regions of hypoperfu sion in six and hyperperfusion in one) and normal in four. In six case s (55%), the interictal and postictal SPECT changed. Among the 11 NES cases, postictal SPECT was abnormal in three cases (all hypoperfusion abnormalities) and normal in eight cases. in no case did the intericta l and postictal SPECT change. This small sample revealed a trend towar d greater hypometabolism (postictal versus interictal) on SPECT for ep ileptic seizures compared to NES (p < 0.12). There were postictal SPEC T changes in two of five seizures unassociated with postictal PRL elev ation. Prolactin was elevated in two cases unassociated with change on SPECT. Comparision of postictal to interictal SPECT may help distingu ish epileptic seizures from NES. Results from SPECT may also help iden tify epileptic seizures unassociated with PRL elevation. (C) 1998 by E lsevier Science Inc. All rights reserved.