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1.
Sensors (Basel) ; 22(19)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36236564

RESUMO

Non-ergonomic execution of repetitive physical tasks represents a major cause of work-related musculoskeletal disorders (WMSD). This study was focused on the pushing and pulling (P&P) of an industrial handcart (which is a generic physical task present across many industries), with the aim to investigate the dependence of P&P execution on the operators' psychological status and the presence of pain syndromes of the upper limbs and spine. The developed acquisition system integrated two three-axis force sensors (placed on the left and right arm) and six electromyography (EMG) electrodes (placed on the chest, back, and hand flexor muscles). The conducted experiment involved two groups of participants (with and without increased psychological scores and pain syndromes). Ten force parameters (for both left and right side), one EMG parameter (for three different muscles, both left and right side), and two time-domain parameters were extracted from the acquired signals. Data analysis showed intergroup differences in the examined parameters, especially in force integral values and EMG mean absolute values. To the best of our knowledge, this is the first study that evaluated the composite effects of pain syndromes, spine mobility, and psychological status of the participants on the execution of P&P tasks-concluding that they have a significant impact on the P&P task execution and potentially on the risk of WMSD. The future work will be directed towards the development of a personalized risk assessment system by considering more muscle groups, supplementary data derived from operators' poses (extracted with computer vision algorithms), and cognitive parameters (extracted with EEG sensors).


Assuntos
Braço , Doenças Musculoesqueléticas , Braço/fisiologia , Eletromiografia , Mãos/fisiologia , Humanos , Músculo Esquelético/fisiologia , Dor
2.
J Nerv Ment Dis ; 206(7): 537-543, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29905664

RESUMO

There is an ongoing debate on the relationship between depression and anxiety, but data on similarities and differences in their predictor profiles are scarce. The aim of our study was to compare family and personality predictors of these disorders among 220 "emerging adults." As such, two clinical groups with noncomorbid depressive and anxiety disorders, and one healthy control group were assessed by sociodemographic questionnaires, Structured Clinical Interview for DSM-IV Disorders and NEO Personality Inventory, Revised. We found significant overlap in family and personality risk profiles, with increasing effect size for predictors common to anxiety and depression when the categories "no disorder-anxiety disorder-depressive disorder" were considered as existing along a continuum. Among the contributing factors we assessed, family psychiatric history, family structure and conflicts with parents were more significant than personality traits. Our study indicates that emerging adults may be more vulnerable to depression than anxiety in the presence of family and personality risk factors.


Assuntos
Transtornos de Ansiedade/diagnóstico , Transtorno Depressivo/diagnóstico , Família/psicologia , Personalidade , Adolescente , Adulto , Transtornos de Ansiedade/psicologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Inventário de Personalidade , Escalas de Graduação Psiquiátrica , Psicometria , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
3.
Sci Rep ; 12(1): 16347, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175434

RESUMO

The compliance of industrial personal protective equipment (PPE) still represents a challenging problem considering size of industrial halls and number of employees that operate within them. Since there is a high variability of PPE types/designs that could be used for protecting various body parts and physiological functions, this study was focused on assessing the use of computer vision algorithms to automate the compliance of head-mounted PPE. As a solution, we propose a pipeline that couples the head ROI estimation with the PPE detection. Compared to alternative approaches, it excludes false positive cases while it largely speeds up data collection and labeling. A comprehensive dataset was created by merging public datasets PictorPPE and Roboflow with author's collected images, containing twelve different types of PPE was used for the development and assessment of three deep learning architectures (Faster R-CNN, MobileNetV2-SSD and YOLOv5)-which in literature were studied only separately. The obtained results indicated that various deep learning architectures reached different performances for the compliance of various PPE types-while the YOLOv5 slightly outperformed considered alternatives (precision 0.920 ± 0.147, and recall 0.611 ± 0.287). It is concluded that further studies on the topic should invest more effort into assessing various deep learning architectures in order to objectively find the optimal ones for the compliance of a particular PPE type. Considering the present technological and data privacy barriers, the proposed solution may be applicable for the PPE compliance at certain checkpoints where employees can confirm their identity.


Assuntos
Aprendizado Profundo , Algoritmos , Humanos , Indústrias , Equipamento de Proteção Individual , Tecnologia
4.
Gen Physiol Biophys ; 30(1): 59-65, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21460413

RESUMO

Transcutaneous functional electrical stimulation is commonly used for strengthening muscle. However, transient effects during stimulation are not yet well explored. The effect of an amplitude change of the stimulation can be described by static model, but there is no differency for different pulse duration. The aim of this study is to present the finite element (FE) model of a transient electrical stimulation on the forearm. Discrete FE equations were derived by using a standard Galerkin procedure. Different tissue conductive and dielectric properties are fitted using least square method and trial and error analysis from experimental measurement. This study showed that FE modeling of electrical stimulation can give the spatial-temporal distribution of applied current in the forearm. Three different cases were modeled with the same geometry but with different input of the current pulse, in order to fit the tissue properties by using transient FE analysis. All three cases were compared with experimental measurements of intramuscular voltage on one volunteer.


Assuntos
Simulação por Computador , Estimulação Elétrica/métodos , Análise de Elementos Finitos , Estimulação Elétrica Nervosa Transcutânea/métodos , Eletricidade , Antebraço/fisiologia , Humanos , Masculino , Modelos Biológicos
5.
Comput Math Methods Med ; 2020: 6320126, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328153

RESUMO

The purpose of this study is the application of pressure sensors in diagnostics and evaluation of the accuracy diagnostics of lumbar disc herniation at levels L4/L5 and L5/S1 using the aforementioned platform. The motivation behind the idea to apply the pressure measurement platform is the fact that the motor weakness of plantar and dorsal flexia of the feet is one of the absolute indications for the operative treatment of patients with lumbar disc herniation at the indicated levels. In patients, MRI diagnosis of the lumbosacral spine served as the ground truth in the diagnosis of herniation at L4/L5 and L5/S1 levels. The inclusive criteria for the study were the proven muscle weakness based on manual muscle tests performed prior to surgery, after seven days of surgery and after physical therapy. The results obtained with the manual muscular test were compared with the results obtained using our platform. The study included 33 patients who met the inclusion criteria. The results of the measurements indicate that the application of our platform with pressure sensors has the same sensitivity diagnostics as a manual muscle test, when done preoperatively and postoperatively. After physical therapy, pressure sensors show statistically significantly better sensitivity compared to the clinical manual muscle test. The obtained results are encouraging in the sense that the pressure platform can be an additional diagnostic method for lumbar disc herniation detection and can indicate the effectiveness of operative treatment and physical therapy after operation. The main advantage of the system is the cost; the whole system with platform and sensors is not expensive.


Assuntos
Diagnóstico por Computador/instrumentação , Deslocamento do Disco Intervertebral/diagnóstico , Vértebras Lombares , Biologia Computacional , Diagnóstico por Computador/estatística & dados numéricos , Feminino , , Humanos , Deslocamento do Disco Intervertebral/fisiopatologia , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Força Muscular , Transdutores de Pressão
6.
IEEE J Biomed Health Inform ; 24(1): 151-159, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30794192

RESUMO

The aim of this research was to analyze objectively the process of disc herniation identification using Bayes Theorem. One of the symptoms of discus hernia is muscle weakness on the foot that is caused by displaced discs in the space of two vertebrae. This fact is used by experts in initial diagnosis of herniated discs and we used it to create non-invasive platform for the same purposes by measuring force values from four sensors placed on both feet (first, second, and fourth metatarsal head as well as the heel). Dataset consisted of several minute force recordings of 56 subjects with discus hernia and 15 healthy individuals during normal standing, standing on forefeet and heels. The subjects were diagnosed by a specialist with either L4/L5 or L5/S1 discus hernia. Collected recordings were processed in several steps including filtering, extraction of forefeet and heel recordings, classification of average values for forefeet, and heel sensors to the groups with or without foot muscle weakness. Application of Bayes Theorem on the attributes of interest showed average 78.3% accuracy with 62.6% sensitivity and 80.9% specificity, while application of naive Bayes Network showed average 83.1% accuracy with 57.6% sensitivity and 88.2% specificity. Very weak or no correlation was observed between gender and disc hernia diagnosis (or obesity type and disc hernia diagnosis). Obtained results show that this method can be used in initial screening of patients and be a supportive tool to doctors to send the same patients for further examination.


Assuntos
Diagnóstico por Computador , Deslocamento do Disco Intervertebral/diagnóstico , Deslocamento do Disco Intervertebral/fisiopatologia , Adulto , Teorema de Bayes , Diagnóstico por Computador/instrumentação , Diagnóstico por Computador/métodos , Diagnóstico Precoce , Desenho de Equipamento , Feminino , Pé/fisiopatologia , Humanos , Deslocamento do Disco Intervertebral/complicações , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/diagnóstico , Debilidade Muscular/etiologia , Debilidade Muscular/fisiopatologia , Pressão , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador
7.
J Sports Sci Med ; 8(4): 584-90, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-24149600

RESUMO

The purpose of this investigation was to use a combination of image processing, force measurements and finite element modeling to calculate deformation of the knee cartilage during jumping. Professional athletes performed jumps analyzed using a force plate and high-speed video camera system. Image processing was performed on each frame of video using a color recognition algorithm. A simplified mass-spring-damper model was utilized for determination of global force and moment on the knee. Custom software for fitting the coupling characteristics was created. Simulated results were used as input data for the finite element calculation of cartilage deformation in the athlete's knee. Computer simulation data was compared with the average experimental ground reaction forces. The results show the three-dimensional mechanical deformation distribution inside the cartilage volume. A combination of the image recognition technology, force plate measurements and the finite element cartilage deformation in the knee may be used in the future as an effective noninvasive tool for prediction of injury during jumping. Key pointsEven there are many existing mathematical models of force distribution during running or jumping (Liu et al, 1998), to our knowledge there is no interdisciplinary approach where imaging processing, finite element modeling and experimental force plate system are employed.The aim is to explore noninvasive deformation in the knee cartilage during athlete's jumping on the force plate.An original image algorithms and software were developed as well as complex mathematical models using high-performance computational power of finite element modeling together with one-dimensional dynamics model.The initial results showed cartilage deformation in the knee and future research will be focused on the methodology and more precisely determination of the stress and strain distribution in the knee cartilage during training phase of sportsman.

8.
Biomed Tech (Berl) ; 64(4): 421-428, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30291782

RESUMO

This paper presents the improved technique for classification of the type of lumbar discus hernia based on fuzzy logic. The reduced mobility of the foot is one of the symptoms of the disease that occurs because of the displaced discs in the space of two vertebrae. This fact was used for non-invasive discus hernia diagnosis by measuring force values from four sensors placed on both feet (first, second and fourth metatarsal head as well as the heel). Hardware and software systems were constructed for the doctor to perform the measurements and have a graphical representation during the measuring procedure. The procedure included measuring force values of 18 subjects during normal standing, standing on forefeet and heels. All subjects were diagnosed by a specialist with either L4/L5 or L5/S1 discus hernia. Filtering and further preprocessing of acquired values included separation of forefeet and heel segments that were used as inputs to fuzzy system. The results showed that the accuracy of such a fuzzy system was around 72%, and the proposed system correctly recognizes healthy individuals. Obtained information about forces on characteristic points on the foot represents useful data in diagnosis which further can be processed in order to be a supportive tool to doctors.


Assuntos
Degeneração do Disco Intervertebral/fisiopatologia , Deslocamento do Disco Intervertebral/fisiopatologia , Disco Intervertebral/fisiologia , Vértebras Lombares/fisiologia , Lógica Fuzzy , Humanos
9.
Technol Health Care ; 27(1): 61-77, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30562912

RESUMO

BACKGROUND: Passenger comfort is affected by many factors. Patient comfort is even more specific due to its mental and physical health condition. OBJECTIVE: Developing a system for monitoring patient transport conditions with the comfort level classification, which is affected by the patient parameters. METHODS: Smartphone with the developed Android application was installed in an EMS to monitor patient transport between medical institutions. As a result, 10 calculated parameters are generated in addition to the GPS data and the subjective comfort level. Three classifiers are used to classify the transportation. At the end, the adjustment of classified comfort levels is performed based on the patient's medical condition, age and gender. RESULTS: Modified SVM classifier provided the best overall classification results with the precision of 90.8%. Furthermore, a model that represents patient sensitivity to transport vibration, based on the patient's medical condition, is proposed and the final classification results are presented. CONCLUSIONS: The Android application is mobile, simple to install and use. According to the obtained results, SVM and Naive Bayes classifier gave satisfying results while KNN should be avoided. The developed model takes transport comfort and the patient's medical condition into consideration, so it is suitable for the patient transport comfort classification.


Assuntos
Aplicativos Móveis , Conforto do Paciente/classificação , Transporte de Pacientes , Adolescente , Adulto , Fatores Etários , Teorema de Bayes , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores Sexuais , Smartphone , Transporte de Pacientes/métodos , Transporte de Pacientes/normas , Adulto Jovem
10.
Environ Sci Pollut Res Int ; 24(27): 21693-21699, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28756602

RESUMO

In recent years, extremely low-frequency electromagnetic field (ELF-EMF) has received considerable attention for its potential biological effects. Numerous studies have shown the role of ELF-EMF in behaviour modulation. The aim of this study was to investigate the effect of short-term ELF-EMF (50 Hz) in the development of anxiety-like behaviour in rats through change hypothalamic oxidative stress and NO. Ten adult male rats (Wistar albino) were divided in two groups: control group-without exposure to ELF-EMF and experimental group-exposed to ELF-EMF during 7 days. After the exposure, time open field test and elevated plus maze were used to evaluate the anxiety-like behaviour of rats. Upon completion of the behavioural tests, concentrations of superoxide anion (O2·-), nitrite (NO2-, as an indicator of NO) and peroxynitrite (ONOO-) were determined in the hypothalamus of the animals. Obtained results show that ELF-EMF both induces anxiety-like behaviour and increases concentrations of O2·- and NO, whereas it did not effect on ONOO- concentration in hypothalamus of rats. In conclusion, the development of anxiety-like behaviour is mediated by oxidative stress and increased NO concentration in hypothalamus of rats exposed to ELF-EMF during 7 days.


Assuntos
Ansiedade/etiologia , Campos Eletromagnéticos/efeitos adversos , Animais , Hipotálamo/metabolismo , Masculino , Óxido Nitroso/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
11.
Comput Math Methods Med ; 2017: 7909282, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28611851

RESUMO

Image segmentation is one of the most common procedures in medical imaging applications. It is also a very important task in breast cancer detection. Breast cancer detection procedure based on mammography can be divided into several stages. The first stage is the extraction of the region of interest from a breast image, followed by the identification of suspicious mass regions, their classification, and comparison with the existing image database. It is often the case that already existing image databases have large sets of data whose processing requires a lot of time, and thus the acceleration of each of the processing stages in breast cancer detection is a very important issue. In this paper, the implementation of the already existing algorithm for region-of-interest based image segmentation for mammogram images on High-Performance Reconfigurable Dataflow Computers (HPRDCs) is proposed. As a dataflow engine (DFE) of such HPRDC, Maxeler's acceleration card is used. The experiments for examining the acceleration of that algorithm on the Reconfigurable Dataflow Computers (RDCs) are performed with two types of mammogram images with different resolutions. There were, also, several DFE configurations and each of them gave a different acceleration value of algorithm execution. Those acceleration values are presented and experimental results showed good acceleration.


Assuntos
Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Computadores , Mamografia/instrumentação , Mamografia/métodos , Mama/diagnóstico por imagem , Feminino , Humanos
12.
Psychiatr Serv ; 67(9): 943-5, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27133728

RESUMO

The dynamics of adolescence require adjustments in psychiatric treatment because of the challenges of this developmental stage in life. This column describes the Day Hospital for Adolescents (DHA) of the Institute of Mental Health in Belgrade, Serbia, which was established in December 2007. The DHA is a holistic program for the treatment of youths ages 15-25 with emotional disorders. The multicomponent therapeutic program includes individual treatment, several group therapeutic activities, and work with patients' families and the school system. An evaluation of data obtained for 102 patients indicated that DHA treatment was associated with significant reductions in depression symptom severity and improved functioning. The adolescents reported a high level of treatment satisfaction. The results suggest that a multicomponent day hospital is an effective treatment modality for adolescents with emotional disorders.


Assuntos
Hospital Dia/métodos , Transtornos Mentais/terapia , Psicoterapia/métodos , Adolescente , Adulto , Humanos , Avaliação de Programas e Projetos de Saúde , Sérvia , Adulto Jovem
13.
Biomed Tech (Berl) ; 60(1): 49-56, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25720034

RESUMO

In this paper, we present a system based on feature extraction techniques for detecting abnormal patterns in digital mammograms and thermograms. A comparative study of texture-analysis methods is performed for three image groups: mammograms from the Mammographic Image Analysis Society mammographic database; digital mammograms from the local database; and thermography images of the breast. Also, we present a procedure for the automatic separation of the breast region from the mammograms. Computed features based on gray-level co-occurrence matrices are used to evaluate the effectiveness of textural information possessed by mass regions. A total of 20 texture features are extracted from the region of interest. The ability of feature set in differentiating abnormal from normal tissue is investigated using a support vector machine classifier, Naive Bayes classifier and K-Nearest Neighbor classifier. To evaluate the classification performance, five-fold cross-validation method and receiver operating characteristic analysis was performed.


Assuntos
Algoritmos , Neoplasias da Mama/diagnóstico , Aprendizado de Máquina , Mamografia/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Termografia/métodos , Feminino , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Technol Health Care ; 23(6): 757-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26409521

RESUMO

BACKGROUND: Reading mammograms is a difficult task and for this reason any development that may improve the performance in breast cancer screening is of great importance. OBJECTIVE: We proposed optimized computer aided diagnosis (CAD) system, equipped with reliability estimate module, for mass detection on digitized mammograms. METHODS: Proposed CAD system consists of four major steps: preprocessing, segmentation, feature extraction and classification. We propose a simple regression function as a threshold function for extraction of potential masses. By running optimization procedure we estimate parameters of the preprocessing and segmentation steps thus ensuring maximum mass detection sensitivity. In addition to the classification, where we tested seven different classifiers, the CAD system is equipped with reliability estimate module. RESULTS: By performing segmentation 91.3% of masses were correctly segmented with 4.14 false positives per image (FPpi). This result is improved in the classification phase where, among the seven tested classifiers, multilayer perceptron neural network achieved the best result including 77.4% sensitivity and 0.49 FPpi. CONCLUSION: By using the proposed regression function and parameter optimization we were able to improve segmentation results comparing to the literature. In addition, we showed that CAD system has high potential for being equipped with reliability estimate module.


Assuntos
Neoplasias da Mama/diagnóstico , Mamografia/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos , Neoplasias da Mama/patologia , Reações Falso-Positivas , Feminino , Humanos , Reprodutibilidade dos Testes
15.
Technol Health Care ; 22(5): 701-15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25059254

RESUMO

Microcalcification clusters appear as groups of small, bright particles with arbitrary shapes on mammographic images. They are the earliest sign of breast carcinomas and their detection is the key for improving breast cancer prognosis. But due to the low contrast of microcalcifications and same properties as noise, it is difficult to detect microcalcification. This work is devoted to developing a system for the detection of microcalcification in digital mammograms. After removing noise from mammogram using the Discrete Wavelet Transformation (DWT), we first selected the region of interest (ROI) in order to demarcate the breast region on a mammogram. Segmenting region of interest represents one of the most important stages of mammogram processing procedure. The proposed segmentation method is based on a filtering using the Sobel filter. This process will identify the significant pixels, that belong to edges of microcalcifications. Microcalcifications were detected by increasing the contrast of the images obtained by applying Sobel operator. In order to confirm the effectiveness of this microcalcification segmentation method, the Support Vector Machine (SVM) and k-Nearest Neighborhood (k-NN) algorithm are employed for the classification task using cross-validation technique.


Assuntos
Doenças Mamárias/diagnóstico , Calcinose/diagnóstico , Mamografia/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Análise de Ondaletas
16.
EXCLI J ; 13: 1204-15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26417334

RESUMO

In this paper, we present a system based on feature extraction techniques and image segmentation techniques for detecting and diagnosing abnormal patterns in breast thermograms. The proposed system consists of three major steps: feature extraction, classification into normal and abnormal pattern and segmentation of abnormal pattern. Computed features based on gray-level co-occurrence matrices are used to evaluate the effectiveness of textural information possessed by mass regions. A total of 20 GLCM features are extracted from thermograms. The ability of feature set in differentiating abnormal from normal tissue is investigated using a Support Vector Machine classifier, Naive Bayes classifier and K-Nearest Neighbor classifier. To evaluate the classification performance, five-fold cross validation method and Receiver operating characteristic analysis was performed. The verification results show that the proposed algorithm gives the best classification results using K-Nearest Neighbor classifier and a accuracy of 92.5%. Image segmentation techniques can play an important role to segment and extract suspected hot regions of interests in the breast infrared images. Three image segmentation techniques: minimum variance quantization, dilation of image and erosion of image are discussed. The hottest regions of thermal breast images are extracted and compared to the original images. According to the results, the proposed method has potential to extract almost exact shape of tumors.

17.
Comput Methods Programs Biomed ; 117(2): 71-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25201585

RESUMO

The main goal of this study was to numerically quantify risk of duodenal stump blowout after Billroth II (BII) gastric resection. Our hypothesis was that the geometry of the reconstructed tract after BII resection is one of the key factors that can lead to duodenal dehiscence. We used computational fluid dynamics (CFD) with finite element (FE) simulations of various models of BII reconstructed gastrointestinal (GI) tract, as well as non-perfused, ex vivo, porcine experimental models. As main geometrical parameters for FE postoperative models we have used duodenal stump length and inclination between gastric remnant and duodenal stump. Virtual gastric resection was performed on each of 3D FE models based on multislice Computer Tomography (CT) DICOM. According to our computer simulation the difference between maximal duodenal stump pressures for models with most and least preferable geometry of reconstructed GI tract is about 30%. We compared the resulting postoperative duodenal pressure from computer simulations with duodenal stump dehiscence pressure from the experiment. Pressure at duodenal stump after BII resection obtained by computer simulation is 4-5 times lower than the dehiscence pressure according to our experiment on isolated bowel segment. Our conclusion is that if the surgery is performed technically correct, geometry variations of the reconstructed GI tract by themselves are not sufficient to cause duodenal stump blowout. Pressure that develops in the duodenal stump after BII resection using omega loop, only in the conjunction with other risk factors can cause duodenal dehiscence. Increased duodenal pressure after BII resection is risk factor. Hence we recommend the routine use of Roux en Y anastomosis as a safer solution in terms of resulting intraluminal pressure. However, if the surgeon decides to perform BII reconstruction, results obtained with this methodology can be valuable.


Assuntos
Duodeno/fisiopatologia , Gastroenterostomia/efeitos adversos , Modelos Biológicos , Estômago/fisiopatologia , Deiscência da Ferida Operatória/etiologia , Deiscência da Ferida Operatória/fisiopatologia , Suturas/efeitos adversos , Animais , Simulação por Computador , Duodeno/cirurgia , Feminino , Gastroenterostomia/instrumentação , Humanos , Masculino , Medição de Risco/métodos , Estômago/cirurgia , Suínos
18.
IEEE Trans Inf Technol Biomed ; 16(2): 272-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21937352

RESUMO

Atherosclerosis is a progressive disease characterized by the accumulation of lipids and fibrous elements in arteries. It is characterized by dysfunction of endothelium and vasculitis, and accumulation of lipid, cholesterol, and cell elements inside blood vessel wall. In this study, a continuum-based approach for plaque formation and development in 3-D is presented. The blood flow is simulated by the 3-D Navier-Stokes equations, together with the continuity equation while low-density lipoprotein (LDL) transport in lumen of the vessel is coupled with Kedem-Katchalsky equations. The inflammatory process was solved using three additional reaction-diffusion partial differential equations. Transport of labeled LDL was fitted with our experiment on the rabbit animal model. Matching with histological data for LDL localization was achieved. Also, 3-D model of the straight artery with initial mild constriction of 30% plaque for formation and development is presented.


Assuntos
Imageamento Tridimensional , Modelos Cardiovasculares , Placa Aterosclerótica/patologia , Algoritmos , Animais , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Viscosidade Sanguínea , Simulação por Computador , Lipoproteínas LDL/metabolismo , Placa Aterosclerótica/fisiopatologia , Coelhos , Estresse Mecânico
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