Abstracts

Rationale: Gelastic seizures have rarely been described as the presenting manifestation of New Onset Refractory Status Epilepticus (NORSE). In this abstract we describe the youngest patient to our knowledge to present with gelastic seizures in the setting of NORSE. Methods: A previously healthy 3 year old girl who presented with an explosive onset of gelastic seizures that were refractory to multiple anti-epileptic medications including Midazolam and Pentobarbital drips. Those seizures arose from the right frontal region (F4-F8) and maintained a stable pattern throughout the different stages of treatment. An extensive metabolic and immunological workup was negative. Her brain magnetic resonance imaging (MRI) was negative, however the Positron Emission Tomography (PET) scan showed a hypermetabolic lesion in the right inferior frontal gyrus. She underwent a depth electrode evaluation that revealed a widespread irritative zone involving the PET "lesion" as well as mesial and neocortical regions in the right frontal lobe. The seizure onset zone was also widespread and non-localizable, however the clinical onset of the gelastic seizures was associated with a clear, well localized epileptiform activity arising from the contacts in the depth of the superior frontal gyrus, which was not overlapping with PET hypermetabolic region. Results: She underwent a right frontal lobectomy sparing the primary motor region in the pre-central gyrus. She has remained seizure free for 8 months since then. The pathological analysis showed focal cortical dysplasia type II in the region of the PET scan hypermetabolism. Conclusions: This case highlights that gelastic seizures can present as focal NORSE from the frontal lobe in the absence of an MRI lesion. PET scan in these cases can be very useful and can guide the surgical workup. To our knowledge this is the youngest patient to present as NORSE with gelastic seizures. Funding: None.