IntroductionWorldwide, more than 50 million people suffer from epilepsy, and there are 16–51 new cases per 100,000 population each year. Up to 30 percent of patients with epilepsy are pharmacoresistant, who are candidates for surgical treatment. Invasive electroencephalography (iEEG) is a mandatory method in the arsenal of epileptic centers, and is gradually becoming the gold standard for invasive determination of boundaries between the affected and functional zones of the cortex and subcortical brain. Treatment costs correlate with the severity of the disease, with patients having uncontrolled seizures incurring eight times the costs compared to those with controlled epilepsy.MethodsTo assess the clinical and cost-effectiveness of the iEEG in the pre-surgical diagnosis of pharmacoresistant epilepsy, a systematic search of literature by keywords in the MEDLINE database was conducted. The search resulted in sixty-six articles. The analysis included twenty studies that met the search criteria.ResultsMost studies including meta-analysis show very low rates of complications of iEEG. Literature data demonstrate cost-effectiveness of the method in patients with pharmacoresistant epilepsy in comparison with continued antiepileptic drug therapy. As an integrated method, rather than a simple method, it takes maximum account of clinical, neurophysiological and anatomical-functional data to achieve accurate localization of the epileptogenic zone. Currently, iEEG is a clinically effective method to improve the safety and specificity of resective surgery.ConclusionsWith the use of iEEG, mortality and disability of patients with pharmacoresistant epilepsy will be significantly reduced. It has also been proven that epilepsy surgery leads to significant financial savings in the treatment of pharmacoresistant epilepsy. The results of the clinical and economic evaluation (mini-HTA report) have been submitted to the Ministry of Healthcare for decision-making on including iEEG in government reimbursement system.
Interictal spike analysis of high-density EEG in patients with partial epilepsy
