Introduction: Glioma-related seizures are a daily concern in the management of patients. As incomplete resection can result in local tumor recurrence and persisting seizures, application of iMRI could be beneficial.
Methods: 85 patients with at least one de novo epileptic seizure at presentation and a neuropathological confirmed glioma enrolled in a prospective randomized iMRI trial were included. The cases were analyzed for short and long-term neurological outcome, progression-free survival (PFS), overall survival (OS), seizure freedom (Engel Class I) and extent of resection (EOR). Wilcoxon non-parametric test or Fisher exact test was applied for continuous or categorical variables.
Results: No patient had intractable epilepsy and a pre-operative seizure duration of more than 6 months was present in 19(22%) patients. 56 (65.9%) patients had an Engel Class 1 outcome. 38 (44.7%) patients had an iMRI, of which 35% patients with LGG and 33% patients with HGG had persistent seizures at follow-up. Overall, there was no significant association between iMRI use and tumor grade (p=0.390) in patients with persistent seizures. In the HGG group, there was no significant difference in the demographic and clinical factors according to the use or not of iMRI. The EOR (<0.0001) and residual volume (<0.0001) were the only significant variable differing between the two subgroups in the LGG patients. 18 (47.4%) patients from the iMRI group underwent further resection after initial iMRI scanning, for which the use of iMRI allowed a 11.4 % and 13% increase of the mean EOR for the LLG and HGG patients. PFS and OS analysis of the patients with HGG, demonstrated a survival benefit trend for patients undergoing iMRI intervention.
Conclusions: iMRI can provide a survival benefit for HGG patients presenting with seizures but this technique doesn’t necessary result in seizure freedom. The use of other electrophysiological measures allowing a better understanding of glioma-related epileptogenesis would be beneficial.
Patient Care: Glioma related seizure control is problematic as the mechanisms linking tumorigenesis and epileptogenesis are poorly understood. This study evaluates the use of iMRI in this special group of patients and highlights the need of incorporating translational research in surgical practice as it might lead to improved seizure rates after tumor surgery which might ultimately result in improved quality of life and survival.
Learning Objectives: By the conclusion of this session, participants should be able to:
1) discuss the role of the role of intraoperative MR imaging in patients with glioma related seizure
2) outline possible future preoperative and intraoperative considerations for improving seizure control after tumor resection.