Computers and biomedical research, an international journal最新文献_第10页

A Computer Model of Intracranial Dynamics Integrated to a Full-Scale Patient Simulator 集成到全尺寸患者模拟器的颅内动力学计算机模型

Computers and biomedical research, an international journal Pub Date : 1998-02-01 DOI: 10.1006/cbmr.1997.1463

William James Thoman, Samsun Lampotang, Dietrich Gravenstein, Jan van der Aa

{"title":"A Computer Model of Intracranial Dynamics Integrated to a Full-Scale Patient Simulator","authors":"William James Thoman, Samsun Lampotang, Dietrich Gravenstein, Jan van der Aa","doi":"10.1006/cbmr.1997.1463","DOIUrl":"10.1006/cbmr.1997.1463","url":null,"abstract":"<div><p>The ability to visualize intracranial dynamics during simulated clinical scenarios is a valuable tool for teaching brain physiology and the consequences of different medical interventions on the brain. Studies have isolated physiologic variables and shown their effects on brain dynamics. However, no studies have shown the combined effects of these variables on intracranial dynamics. This brain model offers one approach that brings all these relationships together and shows how they affect the dynamics of the brain. The brain model obtains its physiologic inputs from a full-scale patient simulator which responds to clinical interventions. This integration allows individuals working on the patient simulator to see the effects of their actions on brain dynamics. The brain model gives a real-time display of intracranial events (cerebral metabolic rate, cerebral blood flow, cerebral blood volume, cerebral perfusion pressure, and intracranial pressure) and responds to changes in the pulmonary and cardiovascular condition of the patient simulator.</p></div>","PeriodicalId":75733,"journal":{"name":"Computers and biomedical research, an international journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1998-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/cbmr.1997.1463","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20484244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 14

SHARE: A Tool to Analyze and Assess Strategies in Health Care Organization Management 分享:一个分析和评估医疗保健组织管理策略的工具

Computers and biomedical research, an international journal Pub Date : 1998-02-01 DOI: 10.1006/cbmr.1997.1466

P.-Y. Boëlle , J.F. Vibert , Philippe Garnerin , A.J. Valleron

引用次数: 1

Serial VCG/ECG Analysis Using Neural Networks 基于神经网络的VCG/ECG串行分析

Computers and biomedical research, an international journal Pub Date : 1998-02-01 DOI: 10.1006/cbmr.1997.1462

M. Sunemark , L. Edenbrandt , H. Holst , L. Sörnmo

{"title":"Serial VCG/ECG Analysis Using Neural Networks","authors":"M. Sunemark , L. Edenbrandt , H. Holst , L. Sörnmo","doi":"10.1006/cbmr.1997.1462","DOIUrl":"10.1006/cbmr.1997.1462","url":null,"abstract":"<div><p>Serial ECG analysis is an important diagnostic tool in which two or more successive ECG recordings from the same patient are compared in order to find changes due to, e.g. myocardial infarction. The present study investigates a new approach to serial analysis which is based on artificial neural networks. Interrecording changes are sometimes falsely detected due to electrode misplacement or positional changes of the heart. In order to compensate for such problems, a new technique for VCG loop alignment was employed. A study population of 1000 patients with two recordings was used and manually scrutinized by three experienced ECG interpreters. Pathological changes indicating newly developed infarcts were found in 256 patients. Different combinations of VCG/ECG measurements served as input data to the neural network. The best performance of the neural network was obtained when ECG and VCG measurements were combined and the resulting sensitivity was 69% at a specificity of 90%. The use of only ECG or VCG measurements reduced the sensitivity to 63% and 60%, respectively. The results indicated that serial analysis based on neural networks did not improve significantly when VCG loop alignment was included.</p></div>","PeriodicalId":75733,"journal":{"name":"Computers and biomedical research, an international journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1998-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/cbmr.1997.1462","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20484246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Comparative Characterization of the Infarcted and Reperfused Ventricular Wall Muscles by Finite Element Analysis and a Myocardial Muscle–Blood Composite Model 用有限元分析和心肌-血液复合模型比较梗死和再灌注心室壁肌肉的特征

Computers and biomedical research, an international journal Pub Date : 1998-02-01 DOI: 10.1006/cbmr.1997.1465

Y.C. Pao , E.L. Ritman

{"title":"Comparative Characterization of the Infarcted and Reperfused Ventricular Wall Muscles by Finite Element Analysis and a Myocardial Muscle–Blood Composite Model","authors":"Y.C. Pao , E.L. Ritman","doi":"10.1006/cbmr.1997.1465","DOIUrl":"10.1006/cbmr.1997.1465","url":null,"abstract":"<div><p>Two methods of characterizing the myocardial fiber bundles' property in the left ventricular wall are reviewed: (1) a myocardial muscle–blood composite model which assumes the myocardial muscle bundles to be incompressible but allows the intramural blood volume fraction to be taken into account, and (2) a two-dimensional finite element method for inverse determination of the myocardial Young's modulus during diastole by matching the computed and tomographically imaged cross-sectional areas near the mid-ventricular, short axis of the left ventricle at the end of diastole. The first method requires the measurements of ventricular wall thickness and the intramural blood volume fraction while the second method requires the image cross-sectional shapes and the corresponding left ventricular chamber pressures. This paper gives greater details of these two methods than in the previously presented progress reports and also presents a scheme for<em>comparative</em>characterization of the myocardial properties for an initial coronary artery occlusion and subsequent reperfusion study of the recently infarcted, left-ventricular wall regions. Furthermore, an attempt is made to correlate the data computed by the two methods. This may eventually lead to a reduction in the number of the required measurements needed for the two methods.</p></div>","PeriodicalId":75733,"journal":{"name":"Computers and biomedical research, an international journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1998-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/cbmr.1997.1465","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20484243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

The Digital Anatomist Information System and Its Use in the Generation and Delivery of Web-Based Anatomy Atlases 数字解剖学家信息系统及其在基于网络的解剖学地图集的生成和传递中的应用

Computers and biomedical research, an international journal Pub Date : 1997-12-01 DOI: 10.1006/cbmr.1997.1461

James F. Brinkley , Scott W. Bradley , John W. Sundsten , Cornelius Rosse

{"title":"The Digital Anatomist Information System and Its Use in the Generation and Delivery of Web-Based Anatomy Atlases","authors":"James F. Brinkley , Scott W. Bradley , John W. Sundsten , Cornelius Rosse","doi":"10.1006/cbmr.1997.1461","DOIUrl":"10.1006/cbmr.1997.1461","url":null,"abstract":"Advances in network and imaging technology, coupled with the availability of 3-D datasets such as the Visible Human, provide a unique opportunity for developing information systems in anatomy that can deliver relevant knowledge directly to the clinician, researcher or educator. A software framework is described for developing such a system within a distributed architecture that includes spatial and symbolic anatomy information resources, Web and custom servers, and authoring and end-user client programs. The authoring tools have been used to create 3-D atlases of the brain, knee and thorax that are used both locally and throughout the world. For the one and a half year period from June 1995-January 1997, the on-line atlases were accessed by over 33,000 sites from 94 countries, with an average of over 4000 \"hits\" per day, and 25,000 hits per day during peak exam periods. The atlases have been linked to by over 500 sites, and have received at least six unsolicited awards by outside rating institutions. The flexibility of the software framework has allowed the information system to evolve with advances in technology and representation methods. Possible new features include knowledge-based image retrieval and tutoring, dynamic generation of 3-D scenes, and eventually, real-time virtual reality navigation through the body. Such features, when coupled with other on-line biomedical information resources, should lead to interesting new ways for managing and accessing structural information in medicine.","PeriodicalId":75733,"journal":{"name":"Computers and biomedical research, an international journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/cbmr.1997.1461","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20391636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 57

A Comparison of the Accuracy and Reproducibility of Digital Three-Dimensional Coronary Artery Reconstructions Using Edge Detection or Videodensitometry 使用边缘检测和视频密度测量的数字三维冠状动脉重建的准确性和再现性的比较

Computers and biomedical research, an international journal Pub Date : 1997-12-01 DOI: 10.1006/cbmr.1997.1453

Joseph B. Muhlestein , Qian Zhang, Daniel J. Parker, Susan D. Horn, Dennis L. Parker, Jeffrey L. Anderson

{"title":"A Comparison of the Accuracy and Reproducibility of Digital Three-Dimensional Coronary Artery Reconstructions Using Edge Detection or Videodensitometry","authors":"Joseph B. Muhlestein , Qian Zhang, Daniel J. Parker, Susan D. Horn, Dennis L. Parker, Jeffrey L. Anderson","doi":"10.1006/cbmr.1997.1453","DOIUrl":"10.1006/cbmr.1997.1453","url":null,"abstract":"<div><p>Global quantitative three-dimensional measurements of coronary arteries may be helpful in determining the functional significance of various forms of coronary pathology. A computerized system has been developed that is capable of performing 3-D reconstruction of digitized images obtained from multiple coronary angiographic views using either automated edge detection (AED) or videodensitometric (VD) techniques. To compare the accuracy and reproducibility of measurements obtained from this system using either technique, stationary and moving coronary aluminum 3-D phantoms, each with 13 branches (diameter 0.58–6.35 mm, length 21.5–64.5 mm), were imaged and reconstructed 10 separate times each. Individual branch lengths and diameters were calculated and compared to each other and to known values. Diameter measurements were compared using either AED or VD. Intraclass correlation coefficients between observed values (ICC) for vessel length were<em>r</em>= 0.89 for the stationary and<em>r</em>= 0.97 for the moving phantom. ICCs for vessel diameter were<em>r</em>= 0.93 (AED) and<em>r</em>= 0.95 (VD) for the stationary and<em>r</em>= 0.98 (AED) and<em>r</em>= 0.97 (VD) for the moving phantom. Mean differences (±SD) between true and observed values [MDTO(±SD)] for vessel length were −1.0 ± 3.9 mm for the stationary and −3.5 ± 3.2 mm for the moving phantom. MDTO(±SD) for vessel diameter were −0.10 ± 0.52 mm (AED) and +0.03 ± 0.30 mm (VD) for the stationary and −0.21 ± 0.44 mm (AED) and −0.12 ± 0.33 (VD) for the moving phantom. We conclude that the quantitative accuracy and reproducibility of measurements obtained by computerized 3-D reconstruction of coronary model phantoms is of high enough quality to warrant further clinical evaluation. VD appears to be more accurate than AED for measuring vessel diameter.</p></div>","PeriodicalId":75733,"journal":{"name":"Computers and biomedical research, an international journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/cbmr.1997.1453","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20394796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Modeling Obesity Using Abductive Networks 利用溯因网络建模肥胖

Computers and biomedical research, an international journal Pub Date : 1997-12-01 DOI: 10.1006/cbmr.1997.1460

R.E. Abdel-Aal , A.M. Mangoud

{"title":"Modeling Obesity Using Abductive Networks","authors":"R.E. Abdel-Aal , A.M. Mangoud","doi":"10.1006/cbmr.1997.1460","DOIUrl":"10.1006/cbmr.1997.1460","url":null,"abstract":"<div><p>This paper investigates the use of abductive-network machine learning for modeling and predicting outcome parameters in terms of input parameters in medical survey data. Here we consider modeling obesity as represented by the waist-to-hip ratio (WHR) risk factor to investigate the influence of various parameters. The same approach would be useful in predicting values of clinical parameters that are difficult or expensive to measure from others that are more readily available. The AIM abductive network machine learning tool was used to model the WHR from 13 other health parameters. Survey data were collected for a randomly selected sample of 1100 persons aged 20 yr and over attending nine primary health care centers at Al-Khobar, Saudi Arabia. Models were synthesized by training on a randomly selected set of 800 cases, using both continuous and categorical representations of the parameters, and evaluated by predicting the WHR value for the remaining 300 cases. Models for WHR as a continuous variable predict the actual values within an error of 7.5% at the 90% confidence limits. Categorical models predict the correct logical value of WHR with an error in only 2 of the 300 evaluation cases. Analytical relationships derived from simple categorical models explain global observations on the total survey population to an accuracy as high as 99%. Simple continuous models represented as analytical functions highlight global relationships and trends. Results confirm the strong correlation between WHR and diastolic blood pressure, cholesterol level, and family history of obesity. Compared to other statistical and neural network approaches, AIM abductive networks provide faster and more automated model synthesis. A review is given of other areas where the proposed modeling approach can be useful in clinical practice.</p></div>","PeriodicalId":75733,"journal":{"name":"Computers and biomedical research, an international journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/cbmr.1997.1460","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20394798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 19

Author Index for Volume 30 第30卷的作者索引

Computers and biomedical research, an international journal Pub Date : 1997-12-01 DOI: 10.1006/cbmr.1997.1467

引用次数: 0

Stochastic Simulation of Ligand–Receptor Interaction 配体-受体相互作用的随机模拟

Computers and biomedical research, an international journal Pub Date : 1997-12-01 DOI: 10.1006/cbmr.1997.1459

Mario Veitl , Ursula Schweiger , Michael L. Berger

{"title":"Stochastic Simulation of Ligand–Receptor Interaction","authors":"Mario Veitl , Ursula Schweiger , Michael L. Berger","doi":"10.1006/cbmr.1997.1459","DOIUrl":"10.1006/cbmr.1997.1459","url":null,"abstract":"<div><p>We have developed an algorithm for the stochastic simulation of ligand–receptor interactions based on 10<sup>4</sup>–10<sup>5</sup>fictitious binding sites. Reversible receptor binding was simulated by alternate random selection of sites, the first selection resulting in “occupation” if the selected site was “free,” the second selection resulting in “dissociation” if the selected site was “occupied.” We show that the mathematical formalism of mass action kinetics is predicted on purely statistical grounds. The model was extended by the introduction of two further selections, simulating a conformational change in the ligand–receptor complex (“receptor isomerization model”). All random selections were gauged separately by “probability barriers,” taking the place of macroscopic kinetic rate constants. Simulation of gradual increases and gradual decreases of the fraction of occupied fictitious binding sites in the receptor isomerization model, using various combinations of “rate constants,” resulted in biexponential time dependencies, in agreement with predictions from the integrated rate equations. Stochastic simulation of molecular processes is a powerful and versatile technique, providing the researcher with a means of studying mechanisms of increasing complexity.</p></div>","PeriodicalId":75733,"journal":{"name":"Computers and biomedical research, an international journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/cbmr.1997.1459","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20394797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Analysis of the Onset and Termination of Repeated Pattern Ventricular Arrhythmias 重复型室性心律失常的起止分析

Computers and biomedical research, an international journal Pub Date : 1997-10-01 DOI: 10.1006/cbmr.1997.1458

D. Sapoznikov, M.H. Luria, M.S. Gotsman

引用次数: 2