Epilepsy Treatment

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