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Interchannel EEG synchronization, as well as its violation, is an important diagnostic sign of a number of diseases. In particular, during an epileptic seizure, such synchronization occurs starting from some pairs of channels up to many pairs in a generalized seizure. Additionally, for example, after traumatic brain injury, the destruction of interneuronal connections occurs, which leads to a violation of interchannel synchronization when performing motor or cognitive tests. Within the framework of a unified approach to the analysis of interchannel EEG synchronization using the ridges of wavelet spectra, two problems were solved. First, the segmentation of the initial data of long-term monitoring of scalp EEG with various artifacts into fragments suspicious of epileptic seizures in order to reduce the total duration of the fragments analyzed by the doctor. Second, assessments of recovery after rehabilitation of cognitive functions in patients with moderate traumatic brain injury. In the first task, the initial EEG was segmented into fragments in which at least two channels were synchronized, and by the adaptive threshold method into fragments with a high value of the EEG power spectral density. Overlapping in time synchronized fragments with fragments of high spectral power density was determined. As a result, the total duration of the fragments for analysis by the doctor was reduced by more than 60 times. In the second task, the network of phase-related EEG channels was determined during the cognitive test before and after rehabilitation. Calculation-logical and spatial-pattern cognitive tests were used. The positive dynamics of rehabilitation was determined during the initialization of interhemispheric connections and connections in the frontal cortex of the brain.

Epilepsy surgery is effective in 30-82% of patients with drug-resistant epilepsy. However, risk factors of unfavorable outcomes after epilepsy surgery require further study., Objective: To evaluate risk factors of favorable and unfavorable long-term postoperative outcomes in patients with drug-resistant epilepsy., Material and Methods: Postoperative outcomes in a large cohort of patients with epilepsy are reported for the first time in the Russian Federation. There were 271 patients with drug-resistant scheduled for surgery. Preoperative examination and surgical treatment were carried out between January 1, 2014 and December 12, 2019 at the Evdokimov Moscow State University of Medicine and Dentistry and Sklifosovsky Research Institute for Emergency Care. We used Engel grading system to assess postoperative outcomes after 12, 24, 48 and 60 months. We distinguished favorable (Engel I-II) and unfavorable (Engel III-IV) outcomes and analyzed the factors influencing postoperative results in these patients., Results: There were 319 surgical procedures in 271 patients (217 primary resections, implantation of vagus nerve stimulator in 31 patients, 9 redo resections and 8 radiosurgical procedures). Focal cortical dysplasia (FCD) was found in 162 (60%) patients, «dual pathology» - in 118 (44%) cases. In 12 months after surgery, favorable outcomes (Engel l-II) were observed in 69% of patients ( n =148), after 24 months - in 71% ( n =127) of patients. Postoperative complications occurred in 6 (1.9%) patients. There was no mortality. The earlier onset of epilepsy ( p =0.01), multifocal ( p =0.002) and bilateral lesions ( p =0.0038) were the most significant risk factors of unfavorable postoperative outcomes., Conclusion: Surgical resection is effective approach for drug-resistant epilepsy.

Objective: To determine the incidence of non-convulsive status epilepticus, epileptiform activity, rhythmic and periodic patterns in patients with acute stroke., Material and Method: An analysis of electroencephalography (EEG) in 86 stroke patients in the neurointensive care unit of the tertiary medical center was performed. Criteria for starting EEG recording were epileptic seizures or clinical suspicion of uncontrolled epileptic status. The ictal-interictal continuum biomarkers and the diagnostic value of EEG for prediction of survival and recovery were assessed., Results: Pathological changes on EEG were recorded in 84% of patients. These patients showed the absence of the dominant occipital rhythm (66%) and hemispheric slowing (42%). Diffuse slowing below the theta range was observed in 41% of patients. EEG reactivity was absent in 20%. Sporadic epileptiform discharges were recorded in 36% of patients and rhythmic and periodic patterns in 26%. Reliable predictors of the unfavorable outcome were the absence of dominant occipital rhythm, lack of reactivity, and low amplitude of the background EEG. No association between the recording of epileptiform activity and the probability of death was shown., Conclusion: The most useful EEG biomarkers for predicting survival are amplitude, dominant frequency of background EEG activity and reactivity to external stimulus. Sporadic epileptiform discharges, rhythmic, and periodic patterns are not mandatory associated with a negative prognosis in stroke patients.

Aim: To evaluate the results of surgical treatment of patients with pharmacoresistant epilepsy., Material and Methods: Examination and surgical treatment of 61 patients with pharmacoresistant forms of symptomatic epilepsy were performed from 01.01.14 to 01.05.16., Results and Conclusion: The results confirmed the safety and efficacy of the surgical treatment of pharmacoresistant epilepsy. After 12 months, seizures were controlled in 69% of operated patients. The necessity of complex examination of all patients with pharmacoresistant epilepsy to make a decision about possible surgery is shown.