Abstracts

Rationale: Diagnosis and treatment of status epilepticus uses clinical and EEG measures. Scalp EEG is a sensitive but non-specific measure of brain regions involved in the ictal process. MR pulsed arterial spin labeling (PASL) measures cerebral blood flow and has been used for localization of seizure onset measure postictally. We reviewed the findings of PASL studies done in 2 patients around the time of prolonged seizures defined as status epilepticus. Methods: A retrospective study was conducted reviewing the electroencephalograms for years 2007 through 2009. The inclusion criteria included a diagnosis of status epilepticus, clinically or electrographically, and MR that included pulsed arterial spin labeling images. Results: Two patients were identified. The number of cases were limited due to the lack of routine PASL acquisition. The first patient had altered mental status and left sided hemiplegia. An MRI was ordered to evaluate for stroke as a possible cause with PASL sequences revealing hyperintensities throughout the right hemisphere. An EEG was subsequently performed due to the PASL findings and demonstrated rhythmic delta seizure activity in the right hemisphere. The second patient had a witnessed 30 minute seizure consisting of left arm clonic movements with loss of consciousness. An MRI, performed during the next day, showed hyperintensities in the right hippocampus on the PASL images. The EEG showed frequent sharp waves within the right frontotemporal region. These findings localized the ictal onset to the temporal region within the right hemisphere. Conclusions: In this small series, PASL identified regions of hyperperfusion which correlated with EEG and clinical findings. In one patient, this technique helped to yield the diagnosis of seizures as a cause of neurological deficit which were initially thought to be due to stroke. Prospective studies of patients suspected of having status epilepticus using this technique would be of value to determine its usefulness where EEG patterns and standard MRI are unable to distinguish between focal deficits due to ischemia versus the occurrence of seizure activity.