Magnetoencephalography-guided epilepsy surgery for children with intractable focal epilepsy: SickKids experience
1Division of Neurology, The Hospital for Sick Children, Toronto, Canada. ayako.ochi@sickkids.ca
Insights
Magnetoencephalography (MEG)-guided epilepsy surgery improves seizure control in children with intractable focal epilepsy. This approach uses advanced imaging to precisely target and resect the seizure source, offering a successful surgical outcome.
Area of Science:
- Pediatric Neurology
- Neurosurgery
- Medical Imaging
Background:
- Intractable focal epilepsy in children poses significant treatment challenges.
- Current diagnostic methods include scalp video EEG (VEEG) and MRI.
- Identifying precise seizure onset zones is crucial for surgical planning.
Purpose of the Study:
- To introduce and evaluate the efficacy of magnetoencephalography (MEG)-guided epilepsy surgery in pediatric patients.
- To detail the multidisciplinary approach integrating MEG, VEEG, and MRI for surgical decision-making.
- To assess the surgical outcomes in controlling seizures in children with intractable focal epilepsy.
Main Methods:
- Utilized scalp VEEG, MRI, and MEG to determine surgical candidacy and plan procedures.
- Designed custom subdural electrode grids based on superimposed 3D MRI and MEG spike source data.
- Employed intraoperative neuronavigation guided by MEG to place electrodes accurately.
- Performed intracranial VEEG to identify seizure onset zones correlating with MEG data.
- Resected the identified seizure onset zone in a second surgical procedure.
Main Results:
- MEG-guided surgery demonstrated successful seizure control in pediatric patients.
- The integration of MEG with VEEG and MRI precisely localized seizure foci.
- The described surgical technique led to favorable outcomes in challenging cases.
Conclusions:
- MEG is a valuable tool for identifying surgical candidates with intractable focal epilepsy.
- MEG-guided epilepsy surgery offers a precise and effective treatment strategy for pediatric patients.
- This combined approach enhances the success rate of epilepsy surgery in children.
Abstract:
We introduced magnetoencephalography (MEG)-guided epilepsy surgery for children with intractable focal epilepsy at The Hospital for Sick Children (SickKids) in Toronto, Canada. Surgical candidacy and decisions on surgical procedure for children with intractable focal epilepsy are based on long-term scalp video EEG (VEEG) results, magnetic resonance imaging (MRI) findings, and the distribution of MEG spike sources. After multidisciplinary discussion at the seizure conference, for the patients requiring intracranial VEEG, custom-made subdural electrode grids are designed using three-dimensional MRI superimposed with MEG spike sources to cover the area of clustered MEG spike sources. At the first surgery, neurosurgeons use the intraoperative neuronavigation system to visualize the area of clustered spike dipoles and somatosensory evoked fields on MEG to place the subdural grid and depth electrodes. At the second surgery, the area of seizure onset and active interictal spike discharges on the intracranial VEEG recording, which usually correlates with the zone of clustered MEG spike sources, is resected. This combination leads to successful surgical outcome to control seizures in these challenging paediatric patients. MEG is a useful tool in children with intractable focal epilepsy to determine the surgical candidacy and focal cortical resection to stop seizures.
