Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.579549
A. Alkhateeb, R. Gaumond
We examined the relative effectiveness of overdamped and of (truncated) underdamped magnetic field pulses in exciting frog sciatic nerve. Waveforms were compared by finding the stimulus magnitude (Vh) corresponding to half-maximal tension developed in gastroenemius muscle. Vh varied inversely with T/sub 0/ the time to peak of the magnetic field.
{"title":"Excitation of frog sciatic nerve using pulsed magnetic fields effect of waveform variations","authors":"A. Alkhateeb, R. Gaumond","doi":"10.1109/IEMBS.1995.579549","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.579549","url":null,"abstract":"We examined the relative effectiveness of overdamped and of (truncated) underdamped magnetic field pulses in exciting frog sciatic nerve. Waveforms were compared by finding the stimulus magnitude (Vh) corresponding to half-maximal tension developed in gastroenemius muscle. Vh varied inversely with T/sub 0/ the time to peak of the magnetic field.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75689380","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575374
G. W. Walker, S. Kun, R. Peura
An Intraventricular Impedance Imaging (III) system, that will be used for assessing electrical and mechanical cardiac properties via an intraventricular catheter, is presently under development. One of the major problems to be solved is the determination of the intraventricular catheter position within the ventricle. Existing methods for determining catheter position within a cardiac ventricle, including X-ray, fluoroscopy and computer tomography, are accurate but cumbersome, expensive, and unable to ascertain the continuous real-time intraventricular catheter position. The purpose of this work was to develop a reconstruction algorithm, based on Artificial Neural Networks (ANN), which will be used to process the electrical information from the catheter to ascertain the continuous, real-time intraventricular catheter position. A back-propagation neural network was trained using results from computer simulations of the III system. The neural network predicted the desired output variables with errors ranging from 0.05% to 1.8% and correlation coefficients (r) ranging from 83% to 99% The RMS error of the output variables was 4.9% These results indicate that ANN have great potential as a tool in determining the continuous real-time intraventricular catheter position.
{"title":"A neural network reconstruction algorithm for Intraventricular Impedance Imaging","authors":"G. W. Walker, S. Kun, R. Peura","doi":"10.1109/IEMBS.1995.575374","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575374","url":null,"abstract":"An Intraventricular Impedance Imaging (III) system, that will be used for assessing electrical and mechanical cardiac properties via an intraventricular catheter, is presently under development. One of the major problems to be solved is the determination of the intraventricular catheter position within the ventricle. Existing methods for determining catheter position within a cardiac ventricle, including X-ray, fluoroscopy and computer tomography, are accurate but cumbersome, expensive, and unable to ascertain the continuous real-time intraventricular catheter position. The purpose of this work was to develop a reconstruction algorithm, based on Artificial Neural Networks (ANN), which will be used to process the electrical information from the catheter to ascertain the continuous, real-time intraventricular catheter position. A back-propagation neural network was trained using results from computer simulations of the III system. The neural network predicted the desired output variables with errors ranging from 0.05% to 1.8% and correlation coefficients (r) ranging from 83% to 99% The RMS error of the output variables was 4.9% These results indicate that ANN have great potential as a tool in determining the continuous real-time intraventricular catheter position.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75757988","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575324
G. Goodman
To answer the question of how technology assessment differs among countries, two background issues must be examined. These are (1) How is health care in the country organized and financed? and (2) What are the country's cultural attitudes towards health care? The cultural influence on methods of technology assessment used in various countries can be seen through a comparison of three culturally diverse countries-Japan, England, and the United States. The focus of the comparison is as follows-an effective methodology of technology assessment should compliment the structure and culture of health care in the country under study. The mandate for the use of decision making tools such as technology assessment for guiding health care decisions is directly related to the degree of centralization inherent in the financing of health care in the country under study.
{"title":"How does technology assessment differ among countries: a discussion of three countries with different styles of technology assessment","authors":"G. Goodman","doi":"10.1109/IEMBS.1995.575324","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575324","url":null,"abstract":"To answer the question of how technology assessment differs among countries, two background issues must be examined. These are (1) How is health care in the country organized and financed? and (2) What are the country's cultural attitudes towards health care? The cultural influence on methods of technology assessment used in various countries can be seen through a comparison of three culturally diverse countries-Japan, England, and the United States. The focus of the comparison is as follows-an effective methodology of technology assessment should compliment the structure and culture of health care in the country under study. The mandate for the use of decision making tools such as technology assessment for guiding health care decisions is directly related to the degree of centralization inherent in the financing of health care in the country under study.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73856025","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575007
R. Zimering, C. Henriquez, D. Harrild
This study uses a fast-Fourier transform method to calculate cardiac transmembrane potentials from extracellular potentials in two-dimensional, anisotropic tissue. Results show agreement between actual and recovered transmembrane potentials of 4% to 7% for activation arising from a single-point stimulus.
{"title":"Recovery of cardiac transmembrane potential from extracellular potential in two-dimensional anisotropic tissue","authors":"R. Zimering, C. Henriquez, D. Harrild","doi":"10.1109/IEMBS.1995.575007","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575007","url":null,"abstract":"This study uses a fast-Fourier transform method to calculate cardiac transmembrane potentials from extracellular potentials in two-dimensional, anisotropic tissue. Results show agreement between actual and recovered transmembrane potentials of 4% to 7% for activation arising from a single-point stimulus.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74329282","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575372
K. Fung, F. Chan, F. K. Lam, P. Poon, J.G. Liu
The application of an artificial neural network filter (ANNF) to give a non-linear estimation of the visual evoked potential (VEP) is presented. A feed forward ANNF is designed and trained by a training set consisting of a training signal and a target signal. The training signal is the raw VEP from a single trial while the target signal has much higher SNR which is achieved by ensemble averaging of 100 trials. The result shows that 10 ensembles is needed by ANNF to generate a satisfactory result against 60 ensembles required by traditional ensemble averaging. VEP from individual trial could be obtained; thus the study of the variation of signal across trials is possible.
{"title":"Visual evoked potential estimation by artificial neural network filter: comparison with the ensemble averaging method","authors":"K. Fung, F. Chan, F. K. Lam, P. Poon, J.G. Liu","doi":"10.1109/IEMBS.1995.575372","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575372","url":null,"abstract":"The application of an artificial neural network filter (ANNF) to give a non-linear estimation of the visual evoked potential (VEP) is presented. A feed forward ANNF is designed and trained by a training set consisting of a training signal and a target signal. The training signal is the raw VEP from a single trial while the target signal has much higher SNR which is achieved by ensemble averaging of 100 trials. The result shows that 10 ensembles is needed by ANNF to generate a satisfactory result against 60 ensembles required by traditional ensemble averaging. VEP from individual trial could be obtained; thus the study of the variation of signal across trials is possible.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78759757","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575285
C. Chou, J. McDougall, C. Ahn, N. Vorea
In vivo studies were conducted to evaluate the effectiveness of electrochemical treatment on animal tumor models. Radiation induced fibrosarcoma tumors were subcutaneously implanted on 157 female C3H/HeJ mice. When the tumor diameter reached 10 mm, 2 to 5 platinum electrodes were inserted into the tumor and treated with direct current. Larger fibrosarcomas were implanted on 34 female Fisher 344 rats, which were treated when the tumors reached 20-30 mm in length. In the second group of 24 rats, 12 rats were treated once, 10 twice and two thrice. Best mice cure rate, three months post treatment, calculated by the Kaplan-Meier method was 59.3% (n=27). For the 24 rats, 6 months post treatment, there were 18 living without tumors (75%). These results indicate that electrochemical treatment is effective on mouse and rat fibrosarcoma tumors.
{"title":"Treating mouse and rat tumors with direct current","authors":"C. Chou, J. McDougall, C. Ahn, N. Vorea","doi":"10.1109/IEMBS.1995.575285","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575285","url":null,"abstract":"In vivo studies were conducted to evaluate the effectiveness of electrochemical treatment on animal tumor models. Radiation induced fibrosarcoma tumors were subcutaneously implanted on 157 female C3H/HeJ mice. When the tumor diameter reached 10 mm, 2 to 5 platinum electrodes were inserted into the tumor and treated with direct current. Larger fibrosarcomas were implanted on 34 female Fisher 344 rats, which were treated when the tumors reached 20-30 mm in length. In the second group of 24 rats, 12 rats were treated once, 10 twice and two thrice. Best mice cure rate, three months post treatment, calculated by the Kaplan-Meier method was 59.3% (n=27). For the 24 rats, 6 months post treatment, there were 18 living without tumors (75%). These results indicate that electrochemical treatment is effective on mouse and rat fibrosarcoma tumors.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76110527","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575040
G. Drzewiecki, V. Bansal, J.K.-J. Li
An arterial tonometer is introduced that can measure arterial compliance as well as pressure. The flexible diaphragm tonometer employs volume feedback control such that the contact surface is apparently rigid. When feedback is disabled, electrical impedance plethysmography of the tonometer compartment permits simultaneous measurement of pressure and volume change in the underlying artery. Applanation pressure is varied in addition to provide compliance as function of pressure. Further analysis yields the arterial pressure-lumen volume curve characteristics.
{"title":"Single artery pressure-lumen volume curve and compliance using flexible diaphragm tonometry","authors":"G. Drzewiecki, V. Bansal, J.K.-J. Li","doi":"10.1109/IEMBS.1995.575040","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575040","url":null,"abstract":"An arterial tonometer is introduced that can measure arterial compliance as well as pressure. The flexible diaphragm tonometer employs volume feedback control such that the contact surface is apparently rigid. When feedback is disabled, electrical impedance plethysmography of the tonometer compartment permits simultaneous measurement of pressure and volume change in the underlying artery. Applanation pressure is varied in addition to provide compliance as function of pressure. Further analysis yields the arterial pressure-lumen volume curve characteristics.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75015813","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575164
P. Windyga, M. Garreau, J. Coatrieux
3D reconstruction of heart arteries is of great interest, not only for diagnostic purposes, but also at a therapeutic level. 3D reconstruction, based on two radiographic images, is a multiple solution problem. The correct solution can only be obtained with a priori knowledge. Up to now, the number of reconstruction solutions, which depends on the image set, has not been studied. Almost all the reconstruction methodologies proposed up to now, try to avoid searching the total solution space. The present research try to determine the number of solutions (size of the solutions space), based on the generation of all the possible reconstruction solutions. This methodology implies the reconstruction of all the possible 3D segments and a selection of subsets that represents possible solutions. A first implementation validated using real data is discussed.
{"title":"Estimation of search-space in 3D coronary artery reconstruction using angiographic biplane images","authors":"P. Windyga, M. Garreau, J. Coatrieux","doi":"10.1109/IEMBS.1995.575164","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575164","url":null,"abstract":"3D reconstruction of heart arteries is of great interest, not only for diagnostic purposes, but also at a therapeutic level. 3D reconstruction, based on two radiographic images, is a multiple solution problem. The correct solution can only be obtained with a priori knowledge. Up to now, the number of reconstruction solutions, which depends on the image set, has not been studied. Almost all the reconstruction methodologies proposed up to now, try to avoid searching the total solution space. The present research try to determine the number of solutions (size of the solutions space), based on the generation of all the possible reconstruction solutions. This methodology implies the reconstruction of all the possible 3D segments and a selection of subsets that represents possible solutions. A first implementation validated using real data is discussed.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75096114","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575163
J. M. Pardo, D. Cabello, J. Heras
In this work the authors describe a knowledge based system for the automatic reconstruction of the 3D shape of the tibia from CT images. The system is structured into two levels. A low level slice by slice segmentation is first carried out. After it, a knowledge based split-and-merge process in space identifies and reconstructs anatomical structures.
{"title":"Automatic 3D shape reconstruction of bones","authors":"J. M. Pardo, D. Cabello, J. Heras","doi":"10.1109/IEMBS.1995.575163","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575163","url":null,"abstract":"In this work the authors describe a knowledge based system for the automatic reconstruction of the 3D shape of the tibia from CT images. The system is structured into two levels. A low level slice by slice segmentation is first carried out. After it, a knowledge based split-and-merge process in space identifies and reconstructs anatomical structures.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72622494","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}
Pub Date : 1995-09-20DOI: 10.1109/IEMBS.1995.575334
K. Behbehani, J. Mokhtar, K. W. Klein
This paper presents a model-base controller for control of induced paralysis during surgery. The controller relies on genetic optimization algorithm for estimating the response model parameters as well as computing the necessary infusion rates.
{"title":"A genetic-based controller for automatic control of induced paralysis","authors":"K. Behbehani, J. Mokhtar, K. W. Klein","doi":"10.1109/IEMBS.1995.575334","DOIUrl":"https://doi.org/10.1109/IEMBS.1995.575334","url":null,"abstract":"This paper presents a model-base controller for control of induced paralysis during surgery. The controller relies on genetic optimization algorithm for estimating the response model parameters as well as computing the necessary infusion rates.","PeriodicalId":20509,"journal":{"name":"Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76475761","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：