Minimally resective epilepsy surgery in MRI-negative children

Area of Science:

• Pediatric Neurology
• Neurosurgery
• Epileptology

Background:

• Epilepsy surgery in children with non-lesional MRI often involves extensive resections.
• The efficacy of smaller, targeted resections in this population is not well-established.

Purpose of the Study:

• To evaluate if smaller resections achieve comparable seizure freedom rates in children with non-lesional focal epilepsy.
• To determine if identifying an epileptogenic epicentre can guide conservative surgical approaches.

Main Methods:

• Retrospective review of 25 children undergoing focal corticectomies within a single lobe or insula.
• Comprehensive pre-surgical evaluation including scalp video-EEG, volumetric MRI, fMRI, EEG source localization, SPECT, and PET.
• Image coregistration to identify convergent biomarkers and tailor resections to the epileptogenic epicentre.

Main Results:

• 60% of children (15/25) achieved seizure freedom at 2 years postoperatively.
• An additional 20% experienced significant seizure reduction (>90% or 50-90%).
• No significant outcome differences were found based on resection location, number of convergent tests, or pathology.

Conclusions:

• Specific biomarkers identified through non-invasive and invasive testing can pinpoint an epileptogenic epicentre in MRI-negative focal epilepsy.
• Resection of small, well-defined epileptogenic epicentres in pediatric focal epilepsy leads to favorable seizure control.