Medical student Faculty of Medicine - Ain Shams University, Cairo, Egypt Cairo, Al Qahirah, Egypt
This abstract has been invited to present during the Better Patient Outcomes through Diversity Platform poster session
Rationale: Patients with refractory neocortical temporal lobe epilepsy (nTLE) remain challenging surgical candidates owing to the difficulty of localizing seizure foci and the proximity of eloquent areas including the language and auditory cortices. Phase I pre-operative evaluation often fails to accurately localize seizure onset zones (SOZ), necessitating the use of invasive intracranial encephalography (iEEG). To our knowledge, “bilateral neocortical temporal lobe epilepsy” (bnTLE) has never been discussed in the literature before. Here we present our experience in the diagnosis and management of three cases of bnTLE who were treated with RNS. Methods: We identified three cases of bnTLE at OHSU who exhibited evidence of bilateral neocortical temporal seizure onset in the posterior superior temporal gyri and had a musical or auditory component to their seizures, with localization confirmed by intracranial EEG monitoring. The electronic medical records of included subjects were retrospectively reviewed. Results: iEEG (depth electrodes with or without subdural electrode strips) localized SOZs to the temporal neocortices in all three cases. All three patients were implanted with bilateral superior temporal gyrus (STG) subdural electrode strips for treatment with responsive neurostimulation (RNS). One patient is currently seizure-free after 3.8 years of treatment with RNS. Another experienced a 50% reduction from 4 disabling seizures to 2 per month when RNS was activated however, stimulation was temporarily inactivated due to side effects of 1-5 second periods of dysphasia. RNS was recently reactivated after adjusting the field of stimulation and inactivating certain lead contacts. The third has experienced a 93% reduction in seizure frequency from 14 disabling seizures to 1 per month. Pre-existing vagus nerve stimulation and AEDs were maintained or adjusted to optimize treatment plan. Conclusions: bnTLE describes a specific subset of neocortical temporal lobe epilepsy that is particularly challenging to diagnose and treat since bilateral resection is not an option due to presence of eloquent areas in the dominant temporal neocortex. This case series suggests that bilateral RNS could be a safe and effective treatment modality for this complex condition. RNS stimulation side effects are rare but warrant further study. The utility of RNS therapy for bnTLE requires further assessment. Funding: Please list any funding that was received in support of this abstract.: N/A
