Video-EEG and ictal SPECT in three patients with both epileptic and non-epileptic seizures

We report scalp EEG and ictal SPECT findings in epileptic (complex partial) and non-epileptic seizures in three patients who experienced both types of event during presurgical investigation of medically intractable epilepsies. In all three patients, ictal SPECT showed localizing changes in cerebral blood flow during epileptic seizures, but showed no change during pseudoseizures. In two patients, the physical manifestations of the pseudoseizures were similar to those of the epileptic seizures, supporting the contention that physiological activation is unlikely to mimic ictal perfusion changes. In one patient, the EEG recording was rendered difficult to interpret by muscle artefact, while SPECT was clear and showed no change. SPECT is not a primary tool for diagnosis of pseudoseizures, but when patients undergoing presurgical investigation are injected during pseudoseizures, then SPECT is unlikely to show misleading perfusion changes due to activation effects, and may aid diagnosis where there is muscle artefact on EEG.