Epilepsy Treatment
Surgical Intervention
Surgery
- May be an option for epileptic patients with seizures uncontrolled by pharmacological therapy and those with surgically remediable epileptic syndrome
- Assess patient for the suitability of curative resective procedures before considering palliative procedures
Curative Resective Procedures
- Aim to eliminate seizures completely that would potentially lead to permanent remission without the need of antiepileptic drugs
- Temporal lobe resection
- The lateral temporal cortex is resected first then the amygdala and hippocampus are resected
- Approximately 70-90% of the patients become seizure-free
- Lesionectomy/focal resection
- Resection of epileptogenic focus based on semiology, EEG finding, neuropsychological tests, magnetic resonance imaging (MRI) and positron emission tomography scan
- Focus could be lesions such as cortical dysplasia, cavernoma, tumor or vascular malformation
- Approximately 50% of the patients become seizure-free
- Extratemporal resection (frontal, parietal and occipital lobectomy)
- Resection of respective section of the brain where epileptogenic focus was identified on electrophysiological tests or functional imaging, with no obvious lesion on MRI
- Approximately 50% of the patients become seizure-free
Palliative Procedures
- Aim to disconnect the epileptogenic area from other parts of the brain to reduce the severity of seizure
- Multiple subpial transections for epileptogenic focus at eloquent functional area
- Anatomical or functional hemispherectomy and hemispherotomy are typically reserved for children with very large areas of seizure onset (eg Rasmussen’s syndrome or cerebral mega-gyrus malformation)
- Corpus callosotomy - for uncontrolled frequent drop attacks
- Focal ablation of epileptogenic focus using image-guided focal laser thermal energy
- Focal ablation of epileptogenic focus using image-guided focal high-dose radiation
Neurostimulation Device Implantations
- Reduce frequency of seizures in patients refractory to pharmacological therapy and who are not suitable for resection or palliative surgical procedures
- Vagus nerve stimulation (VNS)
- Modulation of cerebral neurotransmitter via stimulation of left vagal nerve in the neck
- Around 50% of the patients got >50% reduction in seizure frequency
- Responsive neurostimulation (RNS)
- A device that can record seizure activity directly from the brain and delivers stimulation to stop seizures
- Deep brain stimulation (DBS)
- A surgery that involves implanting an electrode into a specific deep part of the brain and placing a stimulating device under the skin in the chest
- The cyclical stimulation reduces the frequency of the seizure