Student Texas Christian University/University of North Texas Health Science Center School of Medicine Fort Worth, Texas
Rationale: Drug resistant epilepsy (DRE) occurs when seizures continue despite use of two appropriately selected and dosed antiseizure medications (ASMs). Some children with DRE may benefit from epilepsy surgery. Yet, many with DRE receive additional ASM treatment trials before surgical referral potentially delaying benefits of surgical therapy. Here, we sought to identify the characteristics of children with DRE referred for surgical evaluation who failed ≤ and >2 ASMs before referral in order to identify opportunities to reduce the time to surgical evaluation. Methods: We prospectively enrolled children ≤ 18 years of age undergoing epilepsy surgery evaluation at 19 U.S. pediatric epilepsy centers participating in the Pediatric Epilepsy Research Consortium Epilepsy Surgery Database. Children undergoing an initial presurgical evaluation were included. We excluded children without data on number of failed ASMs and children who had prior phase I referral or prior epilepsy surgery. We compared sociodemographic and epilepsy variables of patients failing ≤ and >2 ASMs at the time of epilepsy surgery evaluation. Time to referral was defined as duration from age at DRE diagnosis to age at referral for presurgical evaluation. For characteristics of significance, we compared seizure outcome (Favorable: Engel 1 or 2; Unfavorable: Engel 3 or 4) after surgery between those failing ≤2 and >2 ASMs prior to referral. Statistical analyses was performed with SPSS (Table 1). Results: There were 399 patients that met our inclusion/exclusion criteria (200 ≤2 ASMs, 199 >2). The range of failed ASMs was 0-14. Demographics including gender, ethnicity, race, insurance type, and distance to surgical center were similar between groups. Children failing >2 ASMs had onset of seizures at younger age (median 3y, IQR 0.6-7) compared to children failing ≤2 ASMs (median 5.1, IQR 1-10.9; p< 0.001). Surgical referral was delayed for those failing >2 ASMs (median 1.4y, IQR 0.3-3) compared to those failing ≤2 (median 0.3y, IQR 1-1.03; p< 0.001). Those failing >2 ASMs more often had daily seizures, abnormal neurological exams, and failed treatments other than ASMs prior to referral (Table 1). One hundred thirty eight (35%) children have had surgery and at least one post-op outcome recorded (median 6 m, 0-10m). The presence of daily seizures or abnormal exams did not predict outcome. Children failing >2 ASMs were less often offered surgical treatment after evaluation and more frequently underwent large resections (i.e. hemispherectomy) or procedures intended to be palliative; yet 48% of palliative procedures had favorable outcomes. Conclusions: Additional ASM trials prior to surgical referral are associated with younger age at seizure onset and delays in surgical evaluation. Patients failing >2 ASMs more often have abnormal neurological exam and daily seizures, while also failing treatments other than ASMs prior to surgical referral. Importantly, abnormal exam and seizure frequency do not predict outcome, suggesting delay of surgical evaluation because of these characteristics may be unnecessary. Similarly, children less likely to be rendered seizure free from surgery more often trial >2 ASMs, despite palliative surgical outcomes superior to that expected with additional ASM trials. Recognizing patient characteristics which lead to delayed surgical referral may shorten the duration to surgical therapy with potential for improved outcomes. Funding: Please list any funding that was received in support of this abstract.: None Click here to view image/table
