Surgical epilepsy therapy
Indications
- Focal epilepsy with concomitant presence of pharmacoresistance:
- With focal initial origin and after failure of two antiepileptic drugs (drug-refractory epilepsy). If freedom from seizure recurrence cannot be achieved with medication in temporal lobe epilepsy, resection of a specific brain area (anteromedial temporal lobe or hippocampal region) may be attempted to prevent seizure propagation; early surgery appears to be beneficial.
- To prevent seizure recurrence when the cause is operable, such as a brain tumor or intracranial hemorrhage.
Before surgery
Localization of the epileptogenic area (seizure origin) using clinical, imaging, and electrophysiologic techniques.
The surgical procedure
The classic procedure is two-thirds resection (surgical removal) in the temporal lobe area. Nowadays, the precise localization of the epileptologic area allows circumscribed resections within a brain lobe (topectomy). This leads to sustained seizure freedom in 60-80% of patients while preserving physiological brain functions.
Further notes
- In focal cortical dysplasia (FCD), approximately two-thirds of patients remained seizure-free 12 years after surgery.
- Follow-up of patients operated on for refractory epilepsy (909 patients with focal epilepsy: removal of the subpial seizure focus; 97 patients with generalized epilepsy: total or partial transection of the corpus callosum) revealed a mortality rate per 1,000 patient-years of:
- 25.3 deaths in patients without surgery.
- 8.6 deaths in patients with surgery
- 5.2 Deaths in patients with OP and seizure freedom (≅ rate of age-adjusted general population).
- 10.4 Deaths in patients with surgery without seizure freedom (death rate still 2.5-fold lower than in the group without surgery)
- Neuropathological examination, of biopsies (tissue sample) taken during surgery, showed damaged tissue in 92.3%. Hippocampal sclerosis was the most common finding, at 36.4%. Other common diagnoses were low-grade tumors (23.6%) and malformations of the cerebral cortex (19.8%).
