Abstracts

Rationale: Periictal magnetic resonance imaging (MRI) findings following seizure activity is a recognized phenomenon that is not well understood1. Although transient periictal MRI findings are known to appear in some patients, they are reported anecdotally. Here, we present a unique case of periictal MRI findings located in the occipital lobe in a 34-year-old female with recurrent occipital seizures twice in four years. Methods: A 34-year-old female with a history of recurrent occipital seizures presented with a four-hour history of right visual field changes associated with left hemicranial headache.  She described seeing a spinning beach ball in her right visual field intermittently. These symptoms were similar to those associated with a previous episode of clustered seizures that happened four years ago, and she was which were under complete remission with anti-epileptic medication. EEG (Figure 1) during the patient’s most recent episodes showed left occipital sharps evolving into electro-clinical seizures, lasting 60-70 seconds. MRI with T2/FLAIR and DWI showed diffusion restriction and hyperintense signal throughout left occipital cortex (Figure 2). Given this appearance, the primary diagnostic consideration was an infarct. However, there was no significant mass effect on the ventricular system, an asymmetric increase in vessels seen on the postcontrast imaging suggested luxury perfusion.  MRA of the head/neck showed that the left PCA territory was normal, suggesting the MRI changes are not related to infarction from large vessel occlusion. There was no masslike enhancement or edema to suggest an infectious or neoplastic etiology. MRI scans that were obtained postictally four years ago (Figure 2) also showed T2/FLAIR hyperintensity in left occipital lobe, and follow-up MRI four weeks later showed complete resolution. The patient was discharged after most recent admission with resolving symptoms after additional anti-epileptic agent was given. She was sent with a follow-up MRI scheduled in four weeks. Given her previous history, it is expected that her MRI changes will show complete reversal again. The results from the follow-up MRI will be available at the time of the final presentation. Results: See above. Conclusions: The periictal occipital changes on MRI in this patient are unique because they have been captured on more than one occasion. Periictal MRI findings is a known phenomenon with unknown pathophysiology, although attempts have been made to understand these findings. Though the MRI findings and presentation appear to be stroke-like, seizures should be kept in the differential for better treatment outcomes.Reference:1.     Cole, A. J. (2004), Status Epilepticus and Periictal Imaging. Epilepsia, 45: 72–77. doi:10.1111/j.0013-9580.2004.04014.x Funding: None.