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1.
Crit Rev Biomed Eng ; 51(3): 59-76, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560879

RESUMO

One of the key echographic signs of focal pathology of the pancreas is the presence of formation contours and their nature. Endoscopic ultrasonography has a unique ability to visualize the echographic texture of the pancreatic parenchyma, and also allows you to assess in detail the boundaries and nature of the contours of the tumor formations of the organ due to the proximity of the ultrasound sensor. However, the differential diagnosis of focal pancreatic lesions remains a difficult clinical task due to the similarity of their echosemiotics. One of the ways to objectify and improve the accuracy of ultrasound data is the use of artificial intelligence methods for interpreting images. Improving the quality of differential diagnosis of focal pathology of the pancreas according to endoscopic ultrasonography based on the analysis of the nature of the contours of focal formations using fuzzy mathematical models.


Assuntos
Neoplasias Pancreáticas , Pancreatite Crônica , Humanos , Endossonografia , Diagnóstico Diferencial , Inteligência Artificial , Pancreatite Crônica/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas
2.
Crit Rev Biomed Eng ; 51(2): 1-17, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37551905

RESUMO

This work aims at improving the quality of health assessments, specifically under the influence of occupational risk factors. For this purpose, additional informative indicators are utilized in prognostic and diagnostic models. The models are used to characterize the level of body protection based on oxidative status. A quantitative method is proposed to assess the body's level of protection by means of the levels of lipid peroxidation and antioxidant activity, which characterize the body's oxidative status. A mechanism is developed for integrating the proposed method into prognostic and diagnostic decision rules. The developed rules are in the form of mathematical models used to synthesize hybrid fuzzy decision rules, which are then used to quantify the level of body protection (LBP) against external risk factors, based on the use of protection level functions in terms of lipid peroxidation and antioxidant activity. A mechanism for embedding LBP into predictive and diagnostic decision rules has been proposed. The proposed method is used to predict the occurrence and development of coronary heart disease in railroad locomotive drivers. It was found that to improve the predicting and diagnosing of diseases caused by external pathogenic factors, quantitative assessments of LBP, determined by oxidative status, can be implemented. It has been established that the use of the protection level indicator in predictive decision rules makes it possible to increase the efficiency of the prediction while simultaneously increasing its accuracy.


Assuntos
Antioxidantes , Oxidantes , Humanos , Antioxidantes/metabolismo , Fatores de Risco , Peroxidação de Lipídeos , Prognóstico
3.
Comput Methods Biomech Biomed Engin ; 26(12): 1400-1418, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36305552

RESUMO

Currently, intelligent systems built on a multimodal basis are used to study the functional state of living objects. Its essence lies in the fact that a decision is made through several independent information channels with the subsequent aggregation of these decisions. The method of forming descriptors for classifiers of the functional state of the respiratory system includes the study of the spectral range of the respiratory rhythm and the construction of the wavelet plane of the monitoring electrocardiosignal overlapping this range. Then, variations in the breathing rhythm are determined along the corresponding lines of the wavelet plane. Its analysis makes it possible to select slow waves corresponding to the breathing rhythm and systemic waves of the second order. Analysis of the spectral characteristics of these waves makes it possible to form a space of informative features for classifiers of the functional state of the respiratory system. To construct classifiers of the functional state of the respiratory system, hierarchical classifiers were used. As an example, we took a group of patients with pneumonia with a well-defined diagnosis (radiography, X-ray tomography, laboratory data) and a group of volunteers without pulmonary pathology. The diagnostic sensitivity of the obtained classifier was 76% specificity with a diagnostic specificity of 82%, which is comparable to the results of X-ray studies. It is shown that the corresponding lines of the wavelet planes are correlated with the respiratory system and, using their Fourier analysis, descriptors can be obtained for training neural network classifiers of the functional state of the respiratory system.


Assuntos
Redes Neurais de Computação , Sistema Respiratório , Humanos
4.
Comput Methods Biomech Biomed Engin ; 25(8): 908-921, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34882035

RESUMO

Coronary vascular disease (CHD) is one of the most fatal diseases worldwide. Cardio vascular diseases are not easily diagnosed in early disease stages. Early diagnosis is important for effective treatment, however, medical diagnoses are based on physician's personal experiences of the disease which increase time and testing cost to reach diagnosis. Physicians assess patients' condition based on electrocardiography, sonography and blood test results. In this research we develop classification model of the functional state of the cardiovascular system based on the monitoring of the evolution of the amplitudes of the first and second harmonics of the system rhythm of 0.1 Hz. We separate the signal to three streams; the first stream works with natural electro cardio signal, the other two streams are obtained as a result of frequency analysis of the amplitude- and frequency-detected electro cardio signal. We use sliding window of a demodulated electro cardio signal by means of amplitude and frequency detectors. The developed NN model showed an increase in accuracy of diagnostic efficiency by 11%. The neural network model can be trained to give accurate early detection of disease class.


Assuntos
Sistema Cardiovascular , Doença da Artéria Coronariana , Eletrocardiografia/métodos , Coração/diagnóstico por imagem , Humanos , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador
5.
Crit Rev Biomed Eng ; 50(4): 13-30, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36734864

RESUMO

Ischemic disease has severe impact on patients which makes accurate diagnosis vital for health protection. Improving the quality of prediction of patients with ischemic extremity disease by using hybrid fuzzy model allows for early and accurate prognosis of the development of the disease at various stages. The prediction of critical ischemia of lower extremity (CLI) at various disease stages is complex problem due to inter-related factors. We developed hybrid fuzzy decision rules to classify ischemic severity using clinical thinking (natural intelligence) with artificial intelligence, which allows achieving a new quality in solving complex systemic problems and is innovative. In this study mathematical model was developed to classify the risk level of CLI into: subcritical ischemia, favorable outcome, questionable outcome, and unfavorable outcome. The prognosis is made using such complex indicators as confidence that the patient will develop gangrene of the lower extremity (unfavorable outcome), complex coefficient of variability, and reversibility of the ischemic process. Model accuracy was calculated using representative control samples that showed high diagnostic accuracy and specificity characterizing the quality of prediction are 0.9 and higher, which makes it possible to recommend their use in medical practice.


Assuntos
Inteligência Artificial , Extremidade Inferior , Humanos , Isquemia/diagnóstico
6.
Crit Rev Biomed Eng ; 49(5): 1-12, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35695583

RESUMO

The study focuses on the choice of prevention schemes of the appearance and recurrence of gangrene of the lower extremities, depending on any of the degrees of confidence that the patient will have gangrene or will experience its relapse. The degree of confidence is determined using the fuzzy logic of decision making on the relevant membership functions. For each of the selected classes, an appropriate prevention scheme has been developed, the effectiveness of which was tested using the theory of measuring latent variables and the synthesis of mathematical models of their choice depending on the degree of risk of the occurrence and recurrence of lower extremities gangrene. Model statistical tests showed that compared with traditional prevention schemes the use of the proposed models can increase the rate of positive results in the absence of lower extremities gangrene and reduce the possibility of relapse (recurrent changes by 42%, risk of amputation by 35%).


Assuntos
Gangrena , Extremidade Inferior , Amputação Cirúrgica , Lógica Fuzzy , Gangrena/prevenção & controle , Gangrena/cirurgia , Humanos , Recidiva
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