A. Makki, A. El-Fishawy, A. Abutaleb, C. Hansen, J. Siegel, S. Kesler
Two algorithms for the detection of small changes between images in a noisy environment are described. The first is a nonlinear image processing procedure for reduction and/or suppression of background (clutter), and the enhancement of the small difference between two images. This procedure is based on the recently developed Pontryagin filter and concepts of adaptive noise cancelling and image-sequence analysis. The second procedure is linear and is based on a lattice filter structure. The performance is evaluated through computer simulations and real images.<>
{"title":"Change-detection in image sequences (medical application)","authors":"A. Makki, A. El-Fishawy, A. Abutaleb, C. Hansen, J. Siegel, S. Kesler","doi":"10.1109/NEBC.1988.19412","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19412","url":null,"abstract":"Two algorithms for the detection of small changes between images in a noisy environment are described. The first is a nonlinear image processing procedure for reduction and/or suppression of background (clutter), and the enhancement of the small difference between two images. This procedure is based on the recently developed Pontryagin filter and concepts of adaptive noise cancelling and image-sequence analysis. The second procedure is linear and is based on a lattice filter structure. The performance is evaluated through computer simulations and real images.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122954297","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}
A pattern-recognition algorithm and the required instrumentation to apply it for in vivo human liver tissue differentiation are discussed. The algorithm has been tested successfully, with a confidence interval of 68.27%, on 25 subjects with no history of liver diseases and 15 subjects with different types of abnormalities. Differentiation between normal and abnormal liver tissue is accomplished by calculating the Euclidean distance between a reference vector and a pattern vector. The elements of the reference vector are the precalculated values of the average attenuation and backscattering coefficients of normal liver tissue at each frequency interval in the range from 1.5 to 4.5 MHz. Elements of the pattern vector are the average values of the two coefficients for the liver tissue under consideration at each frequency interval. This distance is a measure of the probability that the liver under consideration is normal. An empirical threshold is selected such that if the distance is less than the threshold, then the liver is declared normal otherwise it is abnormal. The instrumentation implemented is a high speed microprocessor-based data acquisition and analysis system. The system digitizes the backscattered ultrasound signal and stores the digitized data in a microcomputer where it is analyzed.<>
{"title":"In-vivo human liver tissue differentiation","authors":"N. Botros","doi":"10.1109/NEBC.1988.19346","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19346","url":null,"abstract":"A pattern-recognition algorithm and the required instrumentation to apply it for in vivo human liver tissue differentiation are discussed. The algorithm has been tested successfully, with a confidence interval of 68.27%, on 25 subjects with no history of liver diseases and 15 subjects with different types of abnormalities. Differentiation between normal and abnormal liver tissue is accomplished by calculating the Euclidean distance between a reference vector and a pattern vector. The elements of the reference vector are the precalculated values of the average attenuation and backscattering coefficients of normal liver tissue at each frequency interval in the range from 1.5 to 4.5 MHz. Elements of the pattern vector are the average values of the two coefficients for the liver tissue under consideration at each frequency interval. This distance is a measure of the probability that the liver under consideration is normal. An empirical threshold is selected such that if the distance is less than the threshold, then the liver is declared normal otherwise it is abnormal. The instrumentation implemented is a high speed microprocessor-based data acquisition and analysis system. The system digitizes the backscattered ultrasound signal and stores the digitized data in a microcomputer where it is analyzed.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116625335","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}
B. Ha, J. Roper, H. Mallett, J. Ferreiro, C. Lucas, G. Henry
The effects of dopamine on pulmonary and systematic vascular beds were investigated in 8 anesthetized goats (mean age 5+or-1 weeks). Pulmonary artery, aortic, left atrial, and central venous pressures and pulmonary and aortic flows were recorded simultaneously during a 10-minute baseline period and while infusion dopamine at 5, 10, 20, 40 160, and 320 mu g/kg/min. Pulmonary vascular resistance increased significantly at the 20 and 40 mu /kg/min infusion rates, while systemic vascular resistance decreased significantly at these rates. Characteristic impedances indicate generally increased trends. The pulmonary global reflection index indicates increased impedance mismatch at the high infusion rates, while the opposite is true for the systemic reflection index. Right heart work and the energy costs of transporting 1 cm/sup 3/ blood exceed systemic work and energy costs at the high rates of increase the resting tone of the pulmonary vascular bed, while the effect on systemic vascular tone remains unclear. The finding that the work and energy requirements of the heart are substantially increased at the higher infusion rates could affect the therapeutic value of dopamine use at these rates.<>
研究了多巴胺对8只麻醉山羊(平均年龄5±1周龄)肺和系统血管床的影响。同时记录10分钟基线期间肺动脉、主动脉、左心房和中心静脉压以及肺动脉和主动脉流量，同时以5、10、20、40、160和320 μ g/kg/min注射多巴胺。在20和40 mu /kg/min输注速率下，肺血管阻力显著增加，而全身血管阻力显著降低。特征阻抗一般显示增加的趋势。肺整体反射指数表明在高输注速率下阻抗失配增加，而全身反射指数则相反。右心功和输送1cm /sup /血的能量成本在增加肺血管床静息张力的高速率下超过全身功和能量成本，而对全身血管张力的影响尚不清楚。在较高的输注速率下，心脏的功和能量需求显著增加，这一发现可能会影响在这些速率下使用多巴胺的治疗价值。
{"title":"Dopamine effects on infant pulmonary and systemic vasculature","authors":"B. Ha, J. Roper, H. Mallett, J. Ferreiro, C. Lucas, G. Henry","doi":"10.1109/NEBC.1988.19388","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19388","url":null,"abstract":"The effects of dopamine on pulmonary and systematic vascular beds were investigated in 8 anesthetized goats (mean age 5+or-1 weeks). Pulmonary artery, aortic, left atrial, and central venous pressures and pulmonary and aortic flows were recorded simultaneously during a 10-minute baseline period and while infusion dopamine at 5, 10, 20, 40 160, and 320 mu g/kg/min. Pulmonary vascular resistance increased significantly at the 20 and 40 mu /kg/min infusion rates, while systemic vascular resistance decreased significantly at these rates. Characteristic impedances indicate generally increased trends. The pulmonary global reflection index indicates increased impedance mismatch at the high infusion rates, while the opposite is true for the systemic reflection index. Right heart work and the energy costs of transporting 1 cm/sup 3/ blood exceed systemic work and energy costs at the high rates of increase the resting tone of the pulmonary vascular bed, while the effect on systemic vascular tone remains unclear. The finding that the work and energy requirements of the heart are substantially increased at the higher infusion rates could affect the therapeutic value of dopamine use at these rates.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126432748","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}
An optical keyboard emulator (OKE) which allows individuals with severe motor dysfunction to access personal computer systems by small head movements is discussed. The OKE incorporates a focused optical headpointer which can detect one light-emitting diode (LED) on a driven LED keyboard array providing the high information bandwidth of the direct selection technique. The spacing of the LED array, a reference light pointer, and a key memory system provide improvements over commercially available systems allowing individuals without accurate head control to utilize this device. The OKE is microprocessor-based, yielding versatility in keyboard layout and compatibility between computer systems while being completely transparent to the personal computer.<>
{"title":"A microprocessor controlled optical keyboard emulator","authors":"F.C. Hludik, J. LaCourse, P. Caron","doi":"10.1109/NEBC.1988.19373","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19373","url":null,"abstract":"An optical keyboard emulator (OKE) which allows individuals with severe motor dysfunction to access personal computer systems by small head movements is discussed. The OKE incorporates a focused optical headpointer which can detect one light-emitting diode (LED) on a driven LED keyboard array providing the high information bandwidth of the direct selection technique. The spacing of the LED array, a reference light pointer, and a key memory system provide improvements over commercially available systems allowing individuals without accurate head control to utilize this device. The OKE is microprocessor-based, yielding versatility in keyboard layout and compatibility between computer systems while being completely transparent to the personal computer.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126618243","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}
A computer simulation for vibration of the vocal folds is presented. Free and forced oscillations were studied by imposing an impulse and time varying surface forces. The solution was obtained by a semidiscrete numerical method. A finite-element technique was used for solution of the problem in space and a Crank-Nicholson finite-difference method was used for time integration. Each vocal fold was divided into nine parallel layers of equal thickness where a two-dimensional finite method could be applied and layers were coupled to each other by a string law. Triangular elements of different size were selected such that finger elements appeared in the tip of the fold, where the largest and most probable movement was expected. Two different materials, corresponding to the muscle and cover, were considered in the model of vocal cords. Horizontal and vertical displacements of nodal points were obtained as a function of time. In addition, the response of the system to a sinusoidally varying force was obtained and compared with experimental results of an excised larynx of similar loading for validation of model.<>
{"title":"A finite element simulation of vocal folds vibrations","authors":"F. Alipour-Haghighi, I. Titze","doi":"10.1109/NEBC.1988.19380","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19380","url":null,"abstract":"A computer simulation for vibration of the vocal folds is presented. Free and forced oscillations were studied by imposing an impulse and time varying surface forces. The solution was obtained by a semidiscrete numerical method. A finite-element technique was used for solution of the problem in space and a Crank-Nicholson finite-difference method was used for time integration. Each vocal fold was divided into nine parallel layers of equal thickness where a two-dimensional finite method could be applied and layers were coupled to each other by a string law. Triangular elements of different size were selected such that finger elements appeared in the tip of the fold, where the largest and most probable movement was expected. Two different materials, corresponding to the muscle and cover, were considered in the model of vocal cords. Horizontal and vertical displacements of nodal points were obtained as a function of time. In addition, the response of the system to a sinusoidally varying force was obtained and compared with experimental results of an excised larynx of similar loading for validation of model.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120992579","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}
J. Hampshire, J. Strohbehn, M.D. McDaniel, J.L. Waugh, D. James
The Rayleigh and Rice-Nakagami probability density functions (PDFs) are generally accepted models for the RF envelope of ultrasonic backscatter from tissue. However, theoretical computations and experimental results from a tissue equivalent phantom and in vivo canine myocardium suggest that these two PDFs are overly simplistic expressions of a more complex scattering process occurring in tissue. This process is modeled more precisely by the Nakagami-M PDF which is a compact expression for the most general form of the two-dimensional random walk satisfying the central limit theorem. An analysis of ultrasonic backscatter from a Rayleigh phantom is presented with initial results from normal myocardium to substantiate this finding and address its implications for a deeper understanding of the phenomenon of ultrasonic scattering in tissue.<>
{"title":"Probability density of myocardial ultrasonic backscatter","authors":"J. Hampshire, J. Strohbehn, M.D. McDaniel, J.L. Waugh, D. James","doi":"10.1109/NEBC.1988.19413","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19413","url":null,"abstract":"The Rayleigh and Rice-Nakagami probability density functions (PDFs) are generally accepted models for the RF envelope of ultrasonic backscatter from tissue. However, theoretical computations and experimental results from a tissue equivalent phantom and in vivo canine myocardium suggest that these two PDFs are overly simplistic expressions of a more complex scattering process occurring in tissue. This process is modeled more precisely by the Nakagami-M PDF which is a compact expression for the most general form of the two-dimensional random walk satisfying the central limit theorem. An analysis of ultrasonic backscatter from a Rayleigh phantom is presented with initial results from normal myocardium to substantiate this finding and address its implications for a deeper understanding of the phenomenon of ultrasonic scattering in tissue.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124994873","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}
A method has been developed to determine local fiber orientations from scanning electron microscope images of connective tissues. The digitized image is convolved with gradient operators to locate edges and determine their direction. The local directions of the fibers are found and collected into a histogram representing a fiber-orientation distribution function.<>
{"title":"A method for determining fiber direction in soft tissues","authors":"H. Ault, A. Hoffman, P. Grigg","doi":"10.1109/NEBC.1988.19393","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19393","url":null,"abstract":"A method has been developed to determine local fiber orientations from scanning electron microscope images of connective tissues. The digitized image is convolved with gradient operators to locate edges and determine their direction. The local directions of the fibers are found and collected into a histogram representing a fiber-orientation distribution function.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125654166","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}
A noninvasive flicker fusion device to measure impairment due to alcohol or other drugs is discussed. The flicker fusion uses an array of light-emitting diodes and is based on identification. It operates slightly below threshold frequencies and requires a subject to distinguish between patterns of modulated lights and constant background lights.<>
{"title":"A flicker fusion device for measuring alcohol impairment","authors":"B.W. Giroux, A. Drake","doi":"10.1109/NEBC.1988.19327","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19327","url":null,"abstract":"A noninvasive flicker fusion device to measure impairment due to alcohol or other drugs is discussed. The flicker fusion uses an array of light-emitting diodes and is based on identification. It operates slightly below threshold frequencies and requires a subject to distinguish between patterns of modulated lights and constant background lights.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130639999","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}
Electromagnetic scale modeling techniques have been extensively used as a design tool to provide verification of computer model predictions and optimization of design parameters. The model antennas are scaled up in size and down in frequency. The design parameters relate directly to the requirements of obtaining antennas that meet thermal field performance goals. The basic laws of electrodynamic similitude are reviewed and specific applications of the theory to the design of implantable microwave antennas are presented.<>
{"title":"Electromagnetic scale modeling of implantable microwave antennas for cancer hyperthermia","authors":"R.S. Kasevish","doi":"10.1109/NEBC.1988.19401","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19401","url":null,"abstract":"Electromagnetic scale modeling techniques have been extensively used as a design tool to provide verification of computer model predictions and optimization of design parameters. The model antennas are scaled up in size and down in frequency. The design parameters relate directly to the requirements of obtaining antennas that meet thermal field performance goals. The basic laws of electrodynamic similitude are reviewed and specific applications of the theory to the design of implantable microwave antennas are presented.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128960569","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}
Portable muscle stimulators for transcutaneous functional electrical stimulation (FES) are discussed. They provide a single channel of current-controlled output and are intended to be used in the rehabilitation of patients with spinal cord injuries. Several safety features have been incorporated to protect patients from device failure or improper calibration. Six prototypes are currently being used in an FES study. Preliminary results indicate that the stimulators are safe, reliable, and effective.<>
{"title":"A portable current controlled muscle stimulator","authors":"N. Berger, W. Ohley, O. Lemaire, J. Parziale","doi":"10.1109/NEBC.1988.19367","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19367","url":null,"abstract":"Portable muscle stimulators for transcutaneous functional electrical stimulation (FES) are discussed. They provide a single channel of current-controlled output and are intended to be used in the rehabilitation of patients with spinal cord injuries. Several safety features have been incorporated to protect patients from device failure or improper calibration. Six prototypes are currently being used in an FES study. Preliminary results indicate that the stimulators are safe, reliable, and effective.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128367143","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}
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