Combined neuromodulation and resection for functional cortex epilepsy: a case series.

Area of Science:

• Neurosurgery
• Epileptology
• Neuromodulation

Background:

• Medically refractory epilepsy (MRE) often necessitates surgical intervention to resect the seizure onset zone (SOZ).
• Resection of SOZs located in functional cortex (FC) presents challenges due to potential functional deficits.
• A combined surgical and neuromodulation approach may offer a solution for these complex cases.

Purpose of the Study:

• To evaluate the safety and efficacy of combining partial resection with focal neuromodulation (Responsive Neurostimulation [RNS] device) for MRE patients with SOZs in FC.
• To assess seizure outcomes and functional preservation after this combined surgical strategy.

Main Methods:

• Retrospective analysis of seven MRE patients with SOZs in FC treated between January 2015 and December 2022.
• Standard epilepsy preoperative assessment including intracranial EEG and extraoperative stimulation mapping.
• Surgical intervention involved partial resection followed by concurrent implantation of an RNS device, with over 12 months of follow-up.

Main Results:

• Seven patients (4 male, median age 32.3) with SOZs involving sensorimotor, visual, language areas, or insula were included.
• Median follow-up was 3 years; no significant neuropsychological changes were observed.
• Six patients had RNS activated; all achieved good seizure outcomes (5 Engel class I, 2 Engel class II). One patient experienced a nondisabling visual deficit.

Conclusions:

• Maximal safe resection combined with focal neuromodulation is a promising strategy for MRE with SOZs overlapping FC.
• This combined approach effectively improves seizure outcomes while prioritizing functional preservation.
• It offers an alternative to stand-alone resections in challenging epilepsy cases.