An algorithm for detecting events in video EEG monitoring data of patients with craniocerebral injuries

One of the problems solved by analyzing the data of long-term Video EEG monitoring is the differentiation of epileptic and artifact events. For this, not only multichannel EEG signals are used, but also video data analysis, since traditional methods based on the analysis of EEG wavelet spectrograms cannot reliably distinguish an epileptic seizure from a chewing artifact. In this paper, we propose an algorithm for detecting artifact events based on a joint analysis of the level of the optical flow and the ridges of wavelet spectrograms. The preliminary results of the analysis of real clinical data are given. The results show the possibility in principle of reliable distinguishing non-epileptic events from epileptic seizures.The work was carried out within the framework of the state task and partially was supported by the Russian Foundation for Basic Research, the project No 18-29-02035

Detection of epileptic seizures in EEG signals during long-term monitoring of patients after traumatic brain injury

Длительный (несколько суток) мониторинг эпилептиформной активности в скальповой ЭЭГ послеоперационных пациентов после черепномозговой травмы является важной задачей. Наряду с эпилептиформными разрядами в ЭЭГ присутствуют схожие с ними сигналы миографической активности, связанные с жеванием. И эпилептиформная активность и артефакты жевания проявляются в одном частотном диапазоне, что затрудняет их дифференциацию. Для различия эпилептиформной активности от артефактов жевания предложен метод, основанный на анализе вейвлет-спектрограмм ЭЭГ. Вейвлет-спектрограммы ЭЭГ содержат широкополосные пики в моменты времени, соответствующие пик-волновой эпилептиформной активности, с одной стороны, и пикам миографической активности при жевании. Исследуется периодичность этих пиков. Обнаружено отличие в разбросе периодов этих пиков, что является дифференцирующим признаком этих двух видов сигналов. Long-term (several days) monitoring of epileptiform activity in scalp EEG of posttraumatic brain injury patients is an important task. EEG signals contain epileptiform seizures and similar signals of myographic activity associated with chewing. Both epileptiform activity and chewing artifacts appear in the same frequency range, which complicates their differentiation. To distinguish epileptiform activity from chewing artifacts, a method based on the wavelet spectrogram analysis of EEG is proposed. EEG wavelet spectrogram contains broadband peaks at times corresponding to peak-wave epileptiform activity on the one hand, and peaks of myographic activity at chewing on the other hand. The periodicity of these peaks is investigated. The difference in the period dispersion of epileptiform peaks peaks and chewing peaks is found.Исследование выполнено за счёт гранта РФФИ, проект № 18-29-02035 мк. с привлечением средств государственного задания по теме "Фундаментальные основы радиоэлектронных методов для проблем биомедицины"

Surgery for multiple cerebral aneurysms: Literature review and case report [хирургическое Лечение множественных аневризм сосудов гоЛовного мозга: оБзор Литературы и кЛиническое наБЛюдение]

We report a case of simultaneous microsurgical clipping of 5 cerebral aneurysms in a patient with multiple aneurysms of the anterior brain. We analyzed the existing treatment approaches to multiple cerebral aneurysms, including endovascular isolation, microsurgical clipping, as well as surgical tactics in case of subarachnoid hemorrhage. We covered the recommendations for screening, surgical risks, and approaches to aneurysm isolation (single-stage and multiple-stage). Using our own experience (since no strict guidelines are currently available), we concluded that it is important to screen cerebral vessels of all close relatives of patients with multiple and familial cerebral aneurysms. © 2021 ABC-press Publishing House. All right reserved

Electroencephalography in acute stroke [Elektroentsefalografiya v ostrom periode insul'ta]

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.ЦЕЛЬ ИССЛЕДОВАНИЯ: Определить частоту бессудорожного эпилептического статуса (БСЭС), эпилептиформной активности, ритмичных и периодических паттернов у пациентов с острым нарушением мозгового кровообращения (ОНМК). МАТЕРИАЛ И МЕТОДЫ: Исследовали информативность ЭЭГ у 86 пациентов, госпитализированных в отделение реанимации и интенсивной терапии неврологического профиля медицинского центра третьего уровня с диагнозом ОНМК. Критерием начала регистрации были эпилептические приступы или клиническое предположение о БСЭС. Оценивали представленность биомаркеров иктально-интериктального континуума и диагностическую ценность ЭЭГ в отношении прогноза выживания и восстановления сознания. РЕЗУЛЬТАТЫ: Патологические изменения на ЭЭГ были зарегистрированы у 84% больных. Среди них преобладало отсутствие доминирующего затылочного ритма (ДЗР) (66% пациентов) и полушарное замедление (42%). Замедление фонового ритма ниже тета-диапазона мы отметили у 41% пациентов. Реактивность ЭЭГ отсутствовала у 20% больных. Отдельные эпилептиформные графоэлементы были зарегистрированы у 36% пациентов, а ритмичные и периодические паттерны были зарегистрированы у 26% пациентов. Достоверными предикторами неблагоприятного исхода были отсутствие ДЗР, ареактивность, снижение амплитуды и генерализованное замедление фоновой ЭЭГ ниже частот тета-диапазона. Наши данные не показали связи регистрации эпилептиформных графоэлементов и их ритмичных и периодических паттернов с повышением вероятности летального исхода. ЗАКЛЮЧЕНИЕ: Наиболее информативными показателями ЭЭГ для прогнозирования выживания и восстановления сознания являются амплитуда, доминирующая частота фоновой записи и реактивность в ответ на внешнюю стимуляцию. Регистрация спорадических эпилептиформных графоэлементов и ритмичных и периодических паттернов у больных ОНМК не всегда связана с неблагоприятным прогнозом его течения

Electroencephalography in the Acute Phase of Stroke

Objective. To determine the frequency of nonconvulsive status epilepticus (NCSE), epileptiform activity, and rhythmic and periodic patterns in patients with acute cerebrovascular accidents (aCVA). Materials and methods. The informativeness of the EEG was studied in 86 patients hospitalized in the neurology section of the Department of Resuscitation and Intensive Therapy of a level 3 medical center with diagnoses of aCVA. The criterion for starting recordings was an epileptic seizure or clinical suspicion of NCSE. The content of biomarkers of the ictal-interictal continuum and the diagnostic value of the EEG were evaluated in relation to prognoses for survival and recovery of consciousness. Results. Pathological changes in the EEG were seen in 84% of patients. Most patients lacked a dominant occipital rhythm (DOR) (66% of patients) and many showed hemispheric slowing (42%). Slowing of the background rhythm to below the θ range was seen in 41% of patients. EEG reactivity was absent in 20% of patients. Individual epileptiform graphical elements were recorded in 36% of patients, while rhythmic and periodic patterns were recorded in 26%. Significant predictors of unfavorable outcomes were the absence of DOR, areactivity, and decreases in the amplitude and generalized slowing of the background EEG to below the θ range. Our data did not find any link between recording of epileptiform graphic elements or their rhythmic and periodic patterns on the one hand and an increased probability of death on the other. Conclusions. The most informative EEG indicators for prognosticating survival and recovery of consciousness were the amplitude, the dominant frequency of the background recording, and reactivity in response to external stimulation. Recording of sporadic epileptiform graphic elements and rhythmic and periodic patterns in patients with aCVA was not always linked with unfavorable prognoses. © 2021, Springer Science+Business Media, LLC, part of Springer Nature

Resection of a giant fusiform aneurysm of the pericallosal artery with «hemi-bonnet bypass» procedure (Case report and literature review)

A 30-year-old woman with giant fusiform aneurysm of the azygos anterior cerebral artery is reported. Clipping of the aneurysm followed by modeling of pericallosal artery was performed in 2017. However, further enlargement of the aneurysm has been observed for subsequent 2 years. The patient underwent redo surgery with excision of the aneurysm followed by «hemi-bonnet bypass» procedure (anastomosis between superficial temporal artery and anterior cerebral artery with radial artery as an interposition graft). Literature data on reconstructive surgery in the treatment of complex pericallosal artery aneurysms are reviewed. © 2020, Media Sphera Publishing Group. All rights reserved

Brain Bioelectrical Activity in Children with Acute Viral Encephalitis

The aim of the present work was to evaluate changes in brain bioelectrical activity using electroencephalography (EEG) data in children with acute viral encephalitis. A total of 26 children were studied at the Pediatric Scientific Clinical Center for Infectious Diseases, Russian Federal Medical Biological Agency, with clinically confirmed diagnoses of “viral encephalitis.” Boys dominated the sex ratio of 18:8; mean age was 12 ± 2.1 years. All patients were in the acute period (first 14 days). The reference group for EEG analysis consisted of 10 healthy children. The groups were uniform in terms of sex and age. EEG recordings were made in all patients using a Neuron Spectrum 3 encephalograph (Ivanovo, Russia), with visual analysis of the EEG and spectral frequency analysis. Spectral power was evaluated in the α, θ, and δ frequency ranges, and the α/θ, α/δ ratios were also determined. Visual analysis of the EEG showed that 100% of children in the acute period of viral encephalitis showed diffuse slowing with recording of δ and θ frequencies. Focal changes in the form of sharp waves were recorded in 85% of cases (21 patients). Periodic activity was not recorded in even a single case in the study group of patients. Quantitative analysis of the results of statistical processing identified statistically significant decreases in the α/θ ratio (p = 0.035), maximum α (p = 0.046) and minimum θ (p = 0.044) in encephalitis patients as compared with the healthy children group. These data lead to the conclusion that pediatric patients during the acute period of viral encephalitis show significant impairments to the normal α/θ EEG power ratio. This impairment was apparent as a reduction in the power of the α and θ rhythms. It can be suggested that the cause of this reduction is suppression of the functional activity of the thalamus and thalamocortical pathways, as well as the reticular formation of the brain. © 2021, Springer Science+Business Media, LLC, part of Springer Nature