Authors :
Presenting Author: Victoria Vinarsky, DO – Children's National Hospital/The George Washington University School of Medicine
Tayyba Anwar, MD – Children's National Hospital; Dewi Depositario-Cabacar, MD – Children's National Hospital; Katie Havens, PA – Children's National Hospital; Amisha Patel, MD – Children's National Hospital; John Schreiber, MD – Children's National Hospital; Tammy Tsuchida, MD, PhD – Children's National Hospital; Thuy-Anh Vu, MD – Children's National Hospital; Susanne Yoon, MD – Children's National Hospital; Tesfaye Zelleke, MD – Children's National Hospital; Chima Oluigbo, MD – Children's National Hospital; William Gaillard, MD – Children's National Hospital; Nathan Cohen, MD – Children's National Hospital
Rationale: Hippocampal resection can cause verbal memory decline, but poor seizure control can lead to cognitive deficits in patients with temporal lobe epilepsy (TLE). The preservation of the hippocampus may be helpful for the quality of life in children with pharmacoresistant TLE. We aimed to assess seizure outcomes in hippocampal resection versus hippocampal sparing temporal resection surgeries.
Methods: We performed a single center retrospective review of patients aged two months to 22 years who had undergone temporal lobe resection surgery for pharmacoresistant TLE between 2018-2022. Patients were included if they met the following criteria: pathology of focal cortical dysplasia, cortical tuber, or heterotopia with at least one month follow up. Tumors were excluded. Chi-squared analysis was used to assess seizure freedom at one year post-surgical resection. Additionally, independent samples t-test was used to compare seizure outcomes at one year by calculating reported number of days with seizures per month, with a maximal frequency capped at 30 days/month. Engel outcomes were evaluated at last follow-up.
Results: Forty-four patients were screened. Twenty-seven (27) patients were included; 11 (40.7%) female and 16 (59.3%) male. Median age at resection was 15.0 years (IQR 9-18 years). Twenty-one patients (77.8%) had hippocampal resection; six patients (22.2%) had hippocampal sparing temporal resection. There was no difference in number of presurgical seizure days per month between the hippocampal resection (median 16, IQR 3.5-30 days) and hippocampal sparing group (median 8, IQR 3.25-30 days, p=0.50). At one year follow up there was no difference in number of seizure days per month between hippocampal resection (median 0.04, IQR 0-0.31 days) and hippocampal sparing group (median 0.13, IQR 0-3.1 days, p=0.65). One year outcomes are unknown for five in the hippocampal resection group and two in the hippocampal sparing group due to patient receiving care at another institution (n=3), lost to follow up (n=2), and duration of follow-up less than 1 year (n=2). There was no difference in Engel I-IV distribution between hippocampal resection group (Engel I (n=12), Engel II (n=3), Engel III (n=3), Engel IV (n=3), and hippocampal sparing group (Engel I (n=2), Engel II (n=1), Engel III (n=2), Engel IV (n=1), p=0.70). There was also no difference between groups in number of patients who achieved Engel I outcomes (p=0.30). Median length of follow up after resection was 17 months (IQR 7-49 months).
Conclusions: This retrospective study compared seizure outcomes in pediatric patients undergoing temporal lobe resection with and without hippocampal sparing. Our study suggests that hippocampal sparing does not affect seizure-free outcomes at one year in pediatric patients who underwent temporal lobe resection. Future prospective studies should evaluate seizure outcomes and integrate neuropsychological testing to evaluate the effect of extent of hippocampal removal in mesial temporal resections for pharmacoresistant TLE.
Funding: NTC is supported by PERF/CNF Shields Research Grant,CNRI Chief Research Officer Award