Abstracts

Trends in Pre-surgical Evaluation and Epilepsy Surgery in a Pediatric Epilepsy Center Following Implementation of the Ontario Epilepsy Strategy

Abstract number : 2.355
Submission category : 13. Health Services (Delivery of Care, Access to Care, Health Care Models)
Year : 2022
Submission ID : 2204708
Source : www.aesnet.org
Presentation date : 12/4/2022 12:00:00 PM
Published date : Nov 22, 2022, 05:26 AM

Authors :
Omar Yossofzai, BSc – The Hospital for Sick Children; Asthik Biswas, MD – The Hospital for Sick Children; Rahim Moineddin, PhD – University of Toronto; George Ibrahim, MD PhD – The Hospital for Sick Children; James Rutka, MD PhD – The Hospital for Sick Children; Elizabeth Donner, MD – The Hospital for Sick Children; Nicholas Mitsakakis, MSc PhD P.Stat – Children's Hospital of Eastern Ontario Research Institute; Elysa Widjaja, MD MPH PhD – The Hospital for Sick Children

Rationale: The Ontario Epilepsy Strategy (OES) was implemented to increase access for epilepsy surgery evaluation in Ontario, Canada in 2013 amid concerns that too few children who may benefit from epilepsy surgery were being referred for surgical evaluation. The aim of this study was to evaluate trends in pre-surgical evaluation and epilepsy surgery at the largest pediatric epilepsy surgery center in Ontario before and after the implementation of OES.

Methods: This study recruited children who were evaluated for epilepsy surgery between 2001 and 2019 from the Hospital for Sick Children. Exclusion criteria were children with neurodegenerative, metabolic, or inflammatory disorders, epileptic encephalopathies, primary generalized epilepsy, malignant brain tumors, and non-epileptic seizures. For surgical volume, we included resective epilepsy surgery and excluded palliative surgery such as neurostimulation and corpus callosotomy. We assessed the trends in pre-surgical evaluation and surgery before (2001-2013) and after (2014-2019) OES using piecewise Poisson regression. Baseline variables of those who were evaluated and those who underwent surgery, as well as the reasons for not undergoing surgery pre- and post-OES were compared. Piecewise logistic regression was used to compare seizure freedom pre- and post-OES.

Results: There were 1218 children who were evaluated for epilepsy surgery. Following OES implementation, the time from seizure onset to pre-surgical evaluation decreased from 6.2±4.6 to 4.9±4.03 years (p< 0.001), and from seizure onset to epilepsy surgery decreased from 5.5±4.6 to 4.4±4.0 years (p=0.004).  Piecewise Poisson regression showed a significant yearly increase in pre-surgical evaluation volume pre-OES (rate ratio [RR]=1.04, p< 0.001), but no significant change in pre-surgical evaluation volume at OES implementation (RR=0.96, p=0.90), and no yearly trend change post-OES (RR=1.01, p=0.81) compared to pre-OES. There was a significant yearly increase in surgical volume pre-OES (RR=1.08, p< 0.001), but no change in surgical volumes at OES implementation (RR=0.98, p=0.92), and a decreasing trend in yearly surgical volume post-OES (RR=0.91, p=0.026) compared to pre-OES. Among patients who were evaluated but did not proceed to surgery, there was an increase in the proportion of patients without a focal epileptogenic zone post-OES compared to pre-OES (p=0.012). There were no significant differences in the other reasons for not proceeding to surgery pre-OES vs. post-OES, including multiple epileptogenic zones, patient/parent refusal for surgery, risk of complications and seizures controlled with anti-seizure medications (all p >
Health Services (Delivery of Care, Access to Care, Health Care Models)