Estrategia para la toma de decisiones en el reconocimiento automático de estados de sedación anestésica / Decision-making strategy for automatic recognition of sedation states / Estratégia de tomada de decisão para reconhecimento automático de estados de sedação

RESUMEN Introducción: La Anestesiología es la especialidad médica dedicada a la atención específica de los pacientes durante procedimientos quirúrgicos y en cuidados intensivos. Esta especialidad basada en los avances científicos y tecnológicos, ha incorporado el uso del monitoreo electroencefalográfico, facilitando el control continuo de estados de sedación anestésica durante las cirugías, con una adecuada concentración de fármacos. Objetivo: Proponer una estrategia de clasificación para el reconocimiento automático de tres estados de sedación anestésica en señales electroencefalográficas. Método: Se utilizaron con consentimiento informado escrito los registros electroencefalográficos de 27 pacientes sometidos a cirugía abdominal, excluyendo aquellos con antecedentes de epilepsia, enfermedades cerebrovasculares y otras afecciones neurológicas. Se aplicaron en total 12 fármacos anestésicos y dos relajantes musculares con montaje de 19 electrodos según el Sistema Internacional 10-20. Se eliminaron artefactos en los registros y se aplicaron técnicas de Inteligencia artificial para realizar el reconocimiento automático de los estados de sedación. Resultados: Se propuso una estrategia basada en el uso de máquinas de soporte vectorial con algoritmo multiclase Uno-Contra-Resto y la métrica Similitud Coseno, para realizar el reconocimiento automático de tres estados de sedación: profundo, moderado y ligero, en señales registradas por el canal frontal F4 y los occipitales O1 y O2. Se realizó una comparación de la propuesta con otros métodos de clasificación. Conclusiones: Se computa una exactitud balanceada del 92,67 % en el reconocimiento de los tres estados de sedación en las señales registradas por el canal electroencefalográfico F4, lo cual favorece el desarrollo de la monitorización anestésica.

ABSTRACT Introduction: Anesthesiology is the medical specialty concerned with the specific care of patients during surgical and intensive care procedures. This specialty, based on scientific and technological advances, has incorporated the use of electroencephalographic monitoring, facilitating the continuous control in the use of anesthesia for patient´s sedation states during surgeries, with an adequate concentration of drugs. Objective: Proposal for a classification strategy for automatic recognition of three sedation states in electroencephalographic signals. Methods: We used, with written informed consent, the electroencephalographic records of 27 patients undergoing abdominal surgery, excluding those with a history of epilepsy, cerebrovascular disease and other neurological conditions. A total of 12 drugs to produce anesthesia and two muscle relaxants with 19 electrodes, mounted according to the International System 10 -20, were applied. Artifacts in the records were eliminated and artificial intelligence techniques were applied to perform automatic recognition of sedation states. Results: A strategy based on the use of support vector machines with a multiclass algorithm One-against-Rest and the Cosine Similarity metric was proposed to perform the automatic recognition of three sedation states: deep, moderate and light, in signals recorded by the frontal channel F4 and the occipital channels O1 and O2. A comparison was carried out between the proposal showed and other classification methods. Conclusions: A balanced accuracy of 92.67% is computed about the recognition of the three states of sedation in the signals recorded by the electroencephalographic channel F4, which helps in a better anesthetic monitoring process.

RESUMO Introdução: A Anestesiologia é a especialidade médica dedicada ao atendimento específico de pacientes durante procedimentos cirúrgicos e em terapia intensiva. Essa especialidade, baseada nos avanços científicos e tecnológicos, incorporou o uso da monitorização eletroencefalográfica, facilitando o controle contínuo dos estados de sedação anestésica durante as cirurgias, com concentração adequada de fármacos. Objetivo: Propor uma estratégia de classificação para o reconhecimento automático de três estados de sedação anestésica em sinais eletroencefalográficos. Método: Foram utilizados registros eletroencefalográficos de 27 pacientes submetidos à cirurgia abdominal com consentimento informado por escrito, excluindo aqueles com histórico de epilepsia, doenças cerebrovasculares e outras condições neurológicas. Um total de 12 drogas anestésicas e dois relaxantes musculares foram aplicados com um conjunto de 19 eletrodos de acordo com o Sistema Internacional 10-20. Artefatos nos prontuários foram removidos e técnicas de inteligência artificial foram aplicadas para realizar o reconhecimento automático dos estados de sedação. Resultados: Foi proposta uma estratégia baseada no uso de máquinas de vetores de suporte com algoritmo One-Against-Rest multiclasse e a métrica Cosine Similarity para realizar o reconhecimento automático de três estados de sedação: profundo, moderado e leve, em sinais registrados pelo canal frontal F4 e os canais occipitais O1 e O2. Foi feita uma comparação da proposta com outros métodos de classificação. Conclusões: Uma acurácia equilibrada de 92,67% é computada no reconhecimento dos três estados de sedação nos sinais registrados pelo canal eletroencefalográfico F4, o que favorece o desenvolvimento da monitorização anestésica.

Monitorización automática de estados de sedación en señales electroencefalográficas / Automatic monitoring of sedation states in electroencephalographic signals

La anestesia general proporciona al paciente estados de inconciencia, amnesia y analgesia, sin embargo, se reportan casos de despertar intraoperatorio. Debido a la incidencia de este fenómeno y sus efectos psicosomáticos, el Centro de Estudios de Neurociencias, Procesamiento de Imágenes y Señales en la Universidad de Oriente, y el Hospital General Juan Bruno Zayas Alfonso ambos en Santiago de Cuba, Cuba, implementan una metodología que permita detectar automáticamente estados de sedación anestésica aplicando Inteligencia Artificial. Para esto se emplearon las señales registradas por el canal electroencefalográfico F4, nueve parámetros espectrales, las Máquinas de Soporte Vectorial y los Sistemas Neuro-Difusos. En el reconocimiento automático de los estados de Sedación Profunda, Moderada y Ligera se logró una Exactitud de 96.12 por ciento, 90.06 por ciento y 90.24 por ciento respectivamente con las Máquinas de Soporte Vectorial, por lo que se propone el uso del canal electroencefalográfico F4 en la detección de estados anestésicos(AU)

General anesthesia provide the patient states of unconsciousness, amnesia and analgesia, however, cases of intraoperative awareness are reported. Due to the incidence of this phenomenon and the psychosomatic effects it causes, the Neuroscience Studies Center, Images and Signals Processing at the University of Oriente, and the General Hospital Juan Bruno Zayas Alfonso both in Santiago de Cuba, Cuba, implement a methodology that allows the automatic detection of anesthetic sedation states applying Artificial Intelligence. For this, the signals recorded by the electroencephalographic channel F4, nine spectral parameters, the Support Vector Machines and the Neuro-Fuzzy Systems were used. In the automatic recognition of the Sedation States: Profound, Moderate and Mild an Accuracy of 96.12 percent, 90.06 percent and 90.24 percent respectively was achieved with the Support Vector Machines, so the use of the electroencephalographic channel F4 is proposed in the detection of anesthetic states(AU)

Longitudinal electroencephalographic(EEG) finding in anti-N-methyl-D-aspartate(Anti-NMDA) receptor encephalitis / 中国神经精神疾病杂志

Objective To investigate electroencephalographic (EEG) characteristics of anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis during different courses of the disease. Methods This study enrolled 30 cases of anti-NMDA receptor encephalitis patients. A total of 58 EEG monitoring reports and their clinical data were retrospectively analyzed based on different disease courses and severity of disease. According to the clinical stages, EEG data was divided into 4 phases: the initial stage (4), the peak stage (23), the improvement stage (16) and the recovery stage(15). Based on severity of disease during the peak stage, patients were divided into mild group(10 cases) and severe group (13 cases). Results Occipital background activity of the EEG was presented in all patients (100%) in the initial stage and in the recovery stage, in 39.1%(9/23)in the peak stage and in 13/16 (81.2%)in the improvement stage. Generalized rhythmic delta activity (GRDA) pattern could only be detected in the peak stage and the improvement stage. In the peak stage, the main presentation of abnormal EEG was diffuse slow-wave (9 cases, 90%) in mild group. GRDA and extreme delta brush(EDB) were more common in severe group than in mild group(P<0.05). Three focal epilepsy including one status epilepticus were detected in three patients in the peak stage. Focal epileptiform discharges in EEG existed in the whole course. Conclusion Occipital background activity and GRDA pattern are evolved and gradually recovered during the course of the disease. The EEG patterns of GRDA and EDB are common in severe anti- NMDA receptor encephalitis patients in the peak stage. Focal epileptiform discharges in EEG can be detected during the whole course.

The study of relationship between intelligence impairment and interictal epileptiform discharges spreading in mesial temporal lobe epilepsy / 中国神经精神疾病杂志

Objective To investigate the relationship between intelligence impairment and interictal epileptiform discharges spreading in mesial temporal lobe epilepsy(mTLE)patients. Method We assessed 145 patients diagnosed as mTLE and their general materials, analyzed the relationship between intelligence impairment and interictal epileptiform discharges spreading. Results ①Patients with mTLE with longer disease course and higher frequencies of epilepsy tended to have a severe impairment in the total intelligence quotient (IQ), verbal intelligence quotient (vIQ) and performance intelligence quotient (pIQ). ② IQ of was negatively correlated with the condition that interictal epileptiform discharges spreading to the ipsilateral central and parietal region in patients with left lesion; pIQ was negatively correlated with the condition that interictal epileptiform discharges spreading to the ipsilateral frontal region, while positively correlated with the condition that interictal epileptiform discharges spreading to the ipsilateral occipital region in patients with right lesion. Conclusion ①Intelligence impairment of mTLE patients is related with courses and frequencies.②Total IQ is more severely impaired by interictal epileptiform discharges spreading to the ipsilateral central and parietal region in left mTLE patients, and the pIQ is more severely impaired by interictal epileptiform discharges spreading to the ipsilateral frontal region in right mTLE patients.

Clinical effect of electroencephalographic biofeedback therapy in treatment of memory disorders in patients with acute severe toxic encephalopathy / 中华劳动卫生职业病杂志

Objective@#To investigate the clinical effect and safety of electroencephalographic biofeedback therapy in improving memory disorders in patientsin the recovery stage of acute severe toxic encephalopathy.@*Methods@#A total of 52 patients in the recovery stage of acute severe toxic encephalopathy who were hospitalized in our hospital from March 2013 to December 2016 were enrolled and randomly divided into observation group with 27 patients and control group with 25 patients. Both groups were given the drugs to promote the metabolism of brain cells,and the patients in the observation group were given electroencephalographic biofeedback therapy in addition. The Chinese revised version of Wechsler Memory Scale Type A was used to measure memory ability before and after each course of treatment. The treatment outcome was evaluated for both groups.@*Results@#There were no significant differences in the scores of long-term memory,short-term memory, immediate memory, and memory quotient between the two groups before treatment(P>0.05).After the first course of treatment ended, the observation group had significant increases in the scores of forward task,backward task,association,and memory quotient(P<0.05); compared with the control group, the observation group had a significant reduction in the score of backward task(P<0.05).After the second course of treatmentended, the observation group had significant increases in the scores offorward task,backward task,memorization of pictures,reproduction,association,comprehension,and memory quotient,and the control group had significant increases in the scores of reproduction,association,comprehension,and memory quotient(P<0.05); compared with the control group, the observation group had significant increases in the scores of forward task,backward task,memorization of pictures, reproduction, association, comprehension, and memory quotient(P<0.05).Two patients experiencedchest distress, palpitation, and dysphoria during treatment, which did not affect the treatment.@*Conclusion@#Electroencephalographic biofeedback therapy has a certain effect in the treatment of memory disorders in patients with acute severe toxic encephalopathy.

Electroencephalographic Features of Rasmussen's Encephalitis by Stage

PURPOSE: The purpose of this study was to describe the characteristic electroencephalographic features in Rasmussen's encephalitis by stage. METHODS: Patients diagnosed with Rasmussen's encephalitis at Seoul National University Children's Hospital were retrospectively assessed. We analyzed the background activities and epileptiform discharges from electroencephalography (EEG) findings to identify the characteristic EEG features by stage. RESULTS: Seven patients were included in the study. The mean age of first seizure onset was 6.7 years, and the mean duration of the prodromal phase was 21.4 months. During disease course, background activities, such as slow waves, were more prominent and diffuse, and contralateral slow waves were observed. In most patients, focal epileptiform discharges were observed during all stages without change. CONCLUSION: As Rasmussen's encephalitis progresses, background abnormalities in the affected hemisphere increased, and contralateral slow waves occurred. However, characteristic EEG findings that were distinguishable at each stage were not observed.

Analysis of the Inverse Electroencephalographic Problem for Volumetric Dipolar Sources Using a Simplification / Análisis del Problema Inverso Electroencefalográfico para Fuentes Dipolares Volumétricas por Medio de una Simplificación

Objective: To analyze the parameter identification problem for volumetric dipolar sources in the brain from measurement of the EEG on the scalp using a simplification which reduces the multilayer conductive medium problem to one homogeneous medium problem with a null Neumann boundary condition. Methodology: The minimum squares technique is used for parameter identification of the dipolar sources. The simple case in which the head is modelled by concentric circles is developed. This case was chosen because we were able to obtain the solution of the forward problem in exact form and for the simplicity of the exposition. Results: The parameter of the dipolar sources can be identified from the EEG on the scalp using the simplification. For the theoretical analysis the results developed for one homogeneous region are used. The numerical implementation is simpler than the multilayer case and the numerical computation requires minor computational cost. Conclusion: The feasibility for solving the parameter identification problem using the simplification is shown. These results can be extended to the case of concentric spheres and complex geometries but the solution cannot be found in exact form.

Objetivo: Analizar el problema de identificación de los parámetros para fuentes dipolares volumétricas en el cerebro a partir de la medición del EEG en el cuero cabelludo mediante una simplificación que reduce el problema de un medio conductor de múltiples capas a un problema en un medio homogéneo con una condición de Neumann nula en su frontera. Metodología: Se utiliza la técnica de mínimos cuadrados para identificar los parámetros de las fuentes dipolares. Se desarrolla el caso simple en el que la cabeza está modelada por círculos concéntricos debido a que la solución del problema directo se puede calcular en forma exacta y por la sencillez de la exposición. Resultados: Se identifican los parámetros de la fuente dipolar a partir del EEG sobre el cuero cabelludo usando la simplificación. Para el análisis teórico se utilizan los resultados desarrollados para una región homogénea. La implementación numérica es más simple y el cálculo numérico requiere menor costo computacional. Conclusión: Se muestra la factibilidad para resolver el problema de identificar los parámetros de una fuente dipolar por medio de la simplificación. Los resultados pueden ser extendidos al caso de esferas concéntricas y al de geometrías complejas pero la solución del problema directo no puede hallarse en forma exacta.

Simplificación del problema inverso electroencefalográfico a una sola región homogénea con condición de Neumann nula / Simplification of the Inverse Electroencephalographic Problem to One Homogeneous Region with Null Neumann Condition

Objetivo: Presentar una simplificación del Problema Inverso Electroencefalográfico (PIE) del caso de varias capas conductoras a una región homogénea con condición de Neumann Nula. Metodología: Se divide el PIE en tres problemas, dos de los cuales se resuelven usando el potencial medido en el cuero cabelludo y con estas soluciones y el tercer problema se lleva a cabo la simplificación. Para validar la simplificación se genera un ejemplo sintético usando el modelo de esferas concéntricas. Resultados: Por medio de la simplificación la fuente se determina a partir de la ecuación de Poisson con una condición de Neumann nula y un dato adicional sobre la frontera de la región homogénea, el cual se obtiene de la medición. Esto es válido para regiones generales con fronteras suficientemente suaves. Adicionalmente, para el caso de esferas concéntricas, se plantea el PIE para el caso de una fuente dipolar (que representa a focos epilépticos) usando esta simplificación y la técnica de la función de Green. Conclusión: La simplificación presentada aquí permite analizar el PIE en una región lo cual simplifica su estudio teórico y numérico. En particular, puede ser útil para el análisis del problema de identificación de los parámetros de una fuente dipolar.

Objective: To give a simplification of the Inverse Electroencephalographic Problem (IEP) from the case of multilayer conductive medium to the case of a homogeneous region with null Neumann condition. Methodology: IEP is divided in three problems, two of which are resolved using the measurements of potential on the scalp and with these solutions and the third problem the simplification is carried out. In order to validate the simplification a synthetic example is generated using the model of concentric spheres. Results: Through of simplification, the source is determined from the Poisson equation with null Neumann condition and an additional data on the boundary of the homogeneous region, which is obtained from the measurement. This is valid for regions with smooth boundary. Additionally, in the case of concentric spheres, it is statement the identification problem for dipolar sources (representing epileptic focus) using this simplification and Green function. Conclusion: The simplification presented here allows us to analyze the inverse problem in one region, which simplifies the theoretical and numerical study. In particular it may be useful to analyze the problem of parameter identification of a dipolar source.

Clinical Indications and Efficacies of Video-Electroencephalographic Monitoring in the Diagnosis and Treatment of Childhood Epilepsy / 대한간질학회지

PURPOSE: The routine electroencephalography is a pivotal diagnostic study in the evaluation of patients with seizure disorders, but often proves incomplete. Video-Electroencephalographic Monitoring (VEM) is an important diagnostic innovation for intractable epilepsy. We performed this study to evaluate clinical indications and efficacies of VEM in childhood epilepsy. METHODS: The study group consisted of 231 children under the age of 15 year, admitted to the Asan Medical Center for VEM from November 1995 to February 2005. We classified the group on the basis of reasons for admission and did analyze the EEG, the change of diagnosis, treatment modality, and seizure control. RESULTS: Eighty seven (38%) patients underwent VEM for the exact classification of seizure types in patients who have epilepsy (Group I), 95 (41%) for presurgical evaluation (Group II) and 49 (21%) to confirm the diagnosis of a seizure disorder (Group III). The diagnosis was altered after VEM in 111 (48%) cases. The treatment modality was altered after VEM in 161 (70%) patients. In Group I, 53 (61%) had a changed treatment plan, 32 of whom had changes in antiepileptic drug and 7 underwent ketogenic diet. In Group II the treatment modality was changed in 82 (86%) cases, 68 of whom had done epileptic surgery and 6 had done VNS. In Group III, 26 (53%) changed the treatment modality. After VEM study, eventually 149 (65%) patients received changed modality of treatment and 91 (61%) patients of them showed improvement in the seizure control. CONCLUSIONS: VEM showed a high yield in changing diagnosis and management of childhood epilepsy in our study, and we confirmed it is effectively used in the treatment of the intractable childhood epilepsy.

Continuous Electroencephalographic Monitoring in Acute Cerebrovascular Diseases / 国际脑血管病杂志

Continuous electroencephalographic monitoring (CEEG) has been used for clinical monitoring of acute cerebrovascular diseases for nearly 3 decades,but it has not been used as a conventional monitoring approach in clinical practice.In recent 15 years,CEEG technology has made considerable progress,especially in the field of real-time monitoring of acute cerebral ischemia and epilepsy,which has provided a new possible direction for the diagnosis and treatment of acute cerebrovascular diseases.The article briefly comments the application of CEEG in acute cerebrovascular diseases.

Prognostic factors in the functional outcome of viral encephalitis: A three-year review in the Philippine General Hospital

OBJECTIVE: To investigate the clinical, radiological and electroencephalographic characteristics among patients diagnosed with viral encephalitis and correlate these with functional outcome.METHODOLOGY: Twenty-eight adult and 32 pediatric viral encephalitis patients in a tertiary hospital were investigated by thorough chart reviews. Outcome was assessed using the Modified Rankin Scale, with score of 0-2 as good outcome and score of 3-6 as poor outcome. Data were analyzed employing chi-square tests (p value 0.05) and multiple logistic regression analysis.RESULTS: The mean age of patients was 20.2 +/- 16.5 years. There were 31 male and 29 female subjects. History of focal seizures was present in 30 percent of patients, while generalized tonic-clonic type in 63 percent of cases. Twelve percent of the population had status epilepticus. The mean Glasgow Coma Score (GCS) on admission was 11 (range, 4 to 15) Abnormal EEG was present in 84 percent of cases; findings were predominantly generalized slowing of the background activity. CT scan abnormalities were found in 67 percent of patients and these were mainly diffuse cerebral edema and low density lesions, majority involving the frontotemporal region. A total of 39 (67 percent) patients had good outcome and 19 (33 percent) had poor outcome on discharge. Of the 33 patients who had follow up at three months, 31 (94 percent) had good outcome and 2 (6 percent) had poor outcome On univariate analysis, the following factors were correlated with poor outcome on discharge: 1) Age /- 5 years (p On multiple logistic regression analysis, EEG patterns of epileptiform discharges and severe generalized slowing, as well as concomitant infection, were found to have correlation with poor outcome on discharge Of the 32 patients who had serologic tests for HSV, 17 (53 percent) was positive. Modified Rankin Scale scores on discharge and at three months did not differ between HSV-positive and HSV-negative patients (p values, 0.96 and 0.83, respectively). Case fatality rate for herpes encephalitis was 5.88 percent.CONCLUSION: Age, GCS in the acute phase and the history of status epilepticus could influence the mortality and morbidity of the patients. Moreover, this study has demonstrated the prognostic significance of EEG patterns in viral encephalitis as they correlate with functional outcome on discharge.

Clinical Application Topographic Electroencephalography(Computed Mapping of EEF)

Topographic electroencephalographic study(CME) is a newly developed method using a microcomputer system that displays the scalp topograph as the square roots of the average power spectra over each EEG frequency band on a color television screen. CME were applied to thirty patients, Fifteen patients out of them with focal neurologic deficit were analysed about CT scan and conventional EEG. The results of the study were as follows : 1) Comparing the results of CME and conventional EEG reading, CME revealed to be slightly more sensitive in detecting asymmetrical depression of background activity than the conventional reading of the EEG. 2) Topograph EEG study was more accurate than conventional EEG in lateralization of the lesion. 3) CME is very useful in topographic and objective diagnosis of functional lesion, although the source of the data is the same as that from the conventional EEG.