Change in presurgical diagnostic imaging evaluation affects subsequent pediatric epilepsy surgery outcome (P3.242)

Objective: Since 2008, we have changed our presurgical diagnostic evaluation for medically refractory focal epilepsy to include high-resolution epilepsy protocol on 3T MRI, and combined magnetoencephalography and FDG-PET in selected patients with normal or subtle changes on MRI or discordant diagnostic tests. The aim of this study was to evaluate the effectiveness of the change in imaging practice on epilepsy surgery outcome in a tertiary pediatric epilepsy surgery center. Methods: The change in practice occurred in early 2008 and patients were classified based on old or new practice. The patient characteristics, surgical variables, and seizure-free surgical outcome were compared, and the trend in seizure-free outcome over time was assessed. Results: There was a trend for increased abnormal MRI (92[percnt] versus 86[percnt] respectively, p=0.062), and increased utilization of FDG-PET (34[percnt] versus 3[percnt] respectively, p 0.05). During the old practice, there was no significant change in yearly trend of seizure-free outcome (OR=0.960 (95[percnt] CI: 0.875, 1.053), p=0.386). The change in practice in 2008 was associated with a significant improvement in seizure-free outcome (OR=1.535 (95[percnt] CI: 1.100, 2.142), p=0.012). During the new practice, there was a significant positive trend in yearly seizure-free outcome (OR=1.219 (95[percnt] CI: 1.053, 1.411), p=0.008), after adjusting for age at seizure onset, invasive monitoring, location of surgery, type of surgery, histology, MRI, magnetoencephalography and FDG-PET. Significance: We have found an improvement in seizure-free surgical outcome following the change in imaging practice. This study highlights the importance of optimizing and improving presurgical diagnostic imaging evaluation to improve surgical outcome. Disclosure: Dr. Rubinger has nothing to disclose. Dr. Chan has nothing to disclose. Dr. D9Arco has nothing to disclose. Dr. Moineddin has nothing to disclose. Dr. Muthaffar has nothing to disclose. Dr. Rutka has nothing to disclose. Dr. Snead has nothing to disclose. Dr. Smith has nothing to disclose. Dr. Widjaja has nothing to disclose.