Showing papers in "IEEE Engineering in Medicine and Biology Magazine in 1999"
TL;DR: The study of the connections between rhythm, time, and the control of movement was stimulated by the clinical observation that music-therapy techniques that were originally designed for socio-emotional needs elicited motor responses in neurologically impaired patients that were not readily accessible by other therapies.
Abstract: We first present some clinical research results involving rhythmic facilitation and motor control. We then discuss synchronization strategies for sensorimotor coupling pertaining to rhythmic entrainment mechanisms; followed by trajectory cuing and optimization models as they relate to rhythmic entrainment and movement control; and, finally, the outlook for applications that may help rehabilitate motor function. Our interest in the study of the connections between rhythm, time, and the control of movement was stimulated from three directions: (a) the study of high-level motor control in musicians and the effect of rhythmic cues on muscle activity in cello performance; (b) the evidence that auditory rhythmic patterns exert a strong magnet effect on the timing of motor responses; and (c) the clinical observation that music-therapy techniques that were originally designed for socio-emotional needs elicited motor responses in neurologically impaired patients that were not readily accessible by other therapies.
260 citations
TL;DR: The greatest benefits with cochlear implantation have occurred in patients who (1) acquired speech and language before their hearing loss, and (2) have shorter duration of deafness.
Abstract: Cochlear implants have been very successful in restoring partial hearing to profoundly deaf people. Many individuals with implants are now able to communicate and understand speech without lip-reading, and some are able to talk over the phone. Children with implants can develop spoken-language skills and attend normal schools (i.e., schools with normal-hearing children). The greatest benefits with cochlear implantation have occurred in patients who (1) acquired speech and language before their hearing loss, and (2) have shorter duration of deafness. Gradual, but steady, improvements in speech production and speech perception have also occurred in prelingually deafened adults or children.
225 citations
TL;DR: How the findings in the last 20 years of research have led to a combined analysis of sensory and cognitive functions at the level of single neurons and the field potentials is provided.
Abstract: During the "Decade of the Brain", brain science is coming to terms with its ultimate problem: understanding the mechanisms by which the immense number of neurons in the human brain interact to produce the higher cognitive functions. The analysis of the brain's natural frequencies opens a new window toward a combined analysis of sensory and cognitive functions at the level of single neurons and the field potentials. In the last decade, our research group has been strongly involved in the development of nonlinear brain dynamics and with the oscillatory processes of neural assemblies. Recently, three new volumes extensively described this new evolution in neuroscience by concluding that a new integrative neurophysiology and a new "brain theory" is needed in order to confront the problems recognized in this decade of the brain. This article provides a brief outline of how the findings in the last 20 years of research have led to such a development.
155 citations
TL;DR: Using the methodology shown, an active contour method based on level sets is applied to the problem of image-based model construction for computational hemodynamics and constructed models that are appropriate for use with blood flow simulation applications.
Abstract: We have applied an active contour method based on level sets to the problem of image-based model construction for computational hemodynamics The geometric nature of the segmentation algorithm makes it suitable for use with solid modeling techniques Using the methodology shown, we have constructed models that are appropriate for use with blood flow simulation applications We are currently extending these methods to address limitations of the current approach, including issues related to 3-D geometric accuracy and mesh quality
119 citations
TL;DR: The practicality of this technique was investigated through technical considerations required to realize mobile telemedicine, and theoretical analysis verified the feasibility of the proposed technique.
Abstract: We have proposed some techniques for mobile telemedicine and have verified their practical feasibility in experiments. This article presents technical considerations required to realize a practical mobile telemedicine system, techniques developed for multiple medical data transmission, and the satisfactory results of their applications to telemedicine in moving vehicles.
113 citations
TL;DR: It is shown how the recordings vary over a 16-month period after implantation of nerve cuff electrodes in rabbits, and how nerve damage is reflected in the recorded signals.
Abstract: Cuff electrodes for recording of the electro-neurogram from peripheral nerves were introduced by Hoffer [1974] and Stein, et al. [1975]. The cuffs were used to obtain higher signal amplitudes than previously possible, at least in chronic recordings, and to decrease the pick-up of noise, especially from muscles. Cuff electrodes are relatively stable in long-term recordings, but the stability has never been quantified in terms of input-output relationships; i.e., in terms of responses to repeatable stimuli over time. Moreover. The relationship between nerve damage and electrophysiological parameters has never been assessed. In this article, after reviewing the development of cuff electrodes and their applications, we present a long-term study of tactile peripheral nerve signals, electrically activated nerve signals, and impedance measurements. We show how the recordings vary over a 16-month period after implantation of nerve cuff electrodes in rabbits, and how nerve damage is reflected in the recorded signals.
110 citations
TL;DR: A review of various signal-processing techniques that have been used for cochlear prosthesis over the past 25 years is presented.
Abstract: Cochlear implants have been successful in restoring partial hearing to profoundly deaf people. The success of cochlear implants can be attributed to the combined efforts of scientists from various disciplines, including bioengineering, physiology, otolaryngology, speech science, and signal processing. Each of these disciplines contributed to various aspects of the cochlear implant design. Signal processing, in particular, played an important role in the development of different techniques for deriving electrical stimuli from the speech signal. The purpose of this article is to present a review of various signal-processing techniques that have been used for cochlear prosthesis over the past 25 years.
109 citations
TL;DR: The aim of telemedicine is to provide expert-based health care to understaffed remote sites and to provide advanced emergency care through modern telecommunication and information technologies.
Abstract: The term telemedicine refers to the utilization of telecommunication technology for medical diagnosis, treatment, and patient care. Telemedicine enables a physician or specialist at one site to deliver health care, diagnose patients, give intra-operative assistance, provide therapy, or consult with another physician or paramedical personnel at a remote site. Thus, the aim of telemedicine is to provide expert-based health care to understaffed remote sites and to provide advanced emergency care through modern telecommunication and information technologies. This article briefly describes the current status of telemedicine, including its implementation, acceptance, patient satisfaction, service and applications, system configuration and requirements, and research issues to be resolved.
108 citations
TL;DR: The author discusses the accomplishments and challenges in treating sensorineurnal deafness through electrical stimulation with a focus on the treatment of the central nervous system.
Abstract: The author discusses the accomplishments and challenges in treating sensorineurnal deafness through electrical stimulation.
101 citations
TL;DR: A cost-effective portable home unit for electrocardiogram (ECG) and blood pressure (BP) monitoring that helps to overcome past problems by simplifying home installation, operation, and maintenance, and by reducing cost.
Abstract: This article discusses a cost-effective portable home unit for electrocardiogram (ECG) and blood pressure (BP) monitoring. Based on feedback from our previous work concerning a PC-based ECG/BP telemonitoring system, the system described helps to overcome past problems by simplifying home installation, operation, and maintenance, and by reducing cost. The strategy and methodology used in the design and development of the system, as well as the results, are presented.
92 citations
TL;DR: A less invasive method for supplying light power to implant devices, a new wireless energy source that employs a near-infrared laser with a photovoltaic cell with high energy transfer efficiency is proposed.
Abstract: A less invasive method for supplying light power to implant devices, we propose a new wireless energy source that employs a near-infrared laser with a photovoltaic cell. The system can also be used with a rechargeable battery. We discuss the configuration of the system, show its energy transfer efficiency, and discuss its performance during some basic experiments.
TL;DR: The significance of this work includes the development of the hollow metallic micromachined needle arrays for biomedical applications, as well as a discussion of structural, fluidic, and biological design considerations.
Abstract: Micromachined needle arrays have been designed, fabricated, and characterized. The design includes arrays of 25 needles with fluid coupling channels and dual structural supports. Numerical modeling of fluid flow characteristics was performed, demonstrating that the needle coupling channels redistribute flow when the input or output ports are fully restricted. Micromachining technologies have been used to batch fabricate hollow metallic fluid coupled needle arrays. The significance of this work includes the development of the hollow metallic micromachined needle arrays for biomedical applications, as well as a discussion of structural, fluidic, and biological design considerations. The micromachined needle array has many advantages, including (a) reduced trauma at penetration site (small size), (b) greater freedom of patient movement (minimal penetration), (c) a practically pain-free drug delivery device (distribution of force), (d) precise control of penetration depth (needle extension length), and (e) they can be stacked and packaged into a 3-D device for fluid transfer.
Journal Article•
TL;DR: The authors study the pulse spectrum of patients with liver problems, with the goal of using this technique to analyze related conditions.
Abstract: Blood tests and ultrasound scanning are the standard techniques for the diagnosis of liver problems. However, there is no easy assessment of how liver problems affect other parts of the body, such as the spleen, stomach, lung, and gallbladder. Traditional Chinese medicine makes use of pulse analysis to diagnose such conditions. Here, the authors study the pulse spectrum of patients with liver problems, with the goal of using this technique to analyze related conditions.
TL;DR: Two telemonitoring solutions that enable access to information resulting from the monitoring of patients in coronary care units, independent of the location of the system user are presented.
Abstract: Sutil+ is an intelligent monitoring system that is under development. The aim is to endow the system with more intelligent behaviour and to make the presentation of information to the user as flexible as possible, in space, time, and form. We present two telemonitoring solutions that enable access to information resulting from the monitoring of patients in coronary care units, independent of the location of the system user. We concentrate on aspects of data acquisition and storage and, above all, interaction with the user.
TL;DR: The use of a single burst of 50+50 /spl mu/sec biphasic pulses, with an overall duration of about 7 msec, is well tolerated by the patients, causing just one short stimulus sensation instead of a succession of eight stimuli.
Abstract: Electrochemotherapy using rectangular biphasic stimuli and bursts of stimuli, as compared to using monophasic pulses obtained by capacitor discharge, are at least of the same efficacy. The use of small surface electrodes in dermatological treatment yields electrode-skin impedances in the range of 200-400 ohms, with the impedances being almost entirely resistive. Therefore, generator output resistances can be in the range of 10 to 20 ohms. The use of a single burst of 50+50 /spl mu/sec biphasic pulses, with an overall duration of about 7 msec, is well tolerated by the patients, causing just one short stimulus sensation instead of a succession of eight stimuli. The treatment results with the above-described instrumentation are comparable to those reported in the literature. Further studies are necessary in order to better understand the process of electropermeabilization in vivo, so as to determine optimal pulse duration, frequency, and waveform, and to eventually lower field intensity.
TL;DR: In this paper, the pulse spectrum of patients with liver problems was studied, with the goal of using this technique to analyze related conditions, such as the spleen, stomach, lung, and gallbladder.
Abstract: Blood tests and ultrasound scanning are the standard techniques for the diagnosis of liver problems. However, there is no easy assessment of how liver problems affect other parts of the body, such as the spleen, stomach, lung, and gallbladder. Traditional Chinese medicine makes use of pulse analysis to diagnose such conditions. Here, the authors study the pulse spectrum of patients with liver problems, with the goal of using this technique to analyze related conditions.
TL;DR: The goal of this article is to provide a review of deep tissue studies based on two-photon microscopy and to further explore three new developments that have significantly enhanced the power of two-Photon imaging.
Abstract: The goal of this article is to provide a review of deep tissue studies based on two-photon microscopy. We will further explore three new developments that have significantly enhanced the power of two-photon imaging: (1) simultaneous two-photon fluorescence and confocal reflected-light imaging, (2) two-photon video-rate imaging, and (3) fluorescent spectroscopic measurements in deep tissue.
TL;DR: This article reports on the selectivity experimentally obtained with a hand-made 24-fold 2D array with electrodes spaced at 120 /spl mu/m in the rat peroneal nerve and extensor digitorum longum muscle.
Abstract: This article reports on the selectivity experimentally obtained with a hand-made 24-fold 2D array with electrodes spaced at 120 /spl mu/m in the rat peroneal nerve and extensor digitorum longum muscle. We call the device 2D, as all the electrode tips lie in the same plane. The device itself is a 3D multiple needle array. The design and construction of a 128-fold 3D array in silicon- and glass technology is briefly described, as well as the fabrication of a 2D 128-fold array in silicon- and LIGA technology. Special attention is given to efficiency; i.e., the ratio of the number of successful electrodes contacting a single motor fiber to the total number of electrodes in the device. We also discuss whether microfabrication technology will allow a further increase in the number of electrode sites, or if an alternative way of interfacing, namely employing cell cultures on electrode substrates, will lead to higher efficiencies.
TL;DR: It was shown that the fault tolerance of the MLP for rotation, scaling, brightness variety, and other anomalous deformations is good enough to overcome the clinical application problems and the stability, accuracy, and speed of this proposed algorithm are very promising.
Abstract: A multilayer perceptron (MLP) with a genetic algorithm (GA) is proposed to extract feature subimages containing orthodontic landmarks. Simulated images and cephalograms were used to investigate its performance in comparison with the cross-correlation method. From the results of simulated image containing shapes with different geometrical conditions, it was shown that the fault tolerance of the MLP for rotation, scaling, brightness variety, and other anomalous deformations is good enough to overcome the clinical application problems. It was also shown that the stability, accuracy, and speed of this proposed algorithm are very promising. Moreover, the performance of the MLP can be significantly improved by collecting more "representative" false patterns. The GA is a good approach to speed up the process of feature subimage extraction based on the fitness evaluated using the MLP.
TL;DR: Clinical findings on the accuracy of tele-otolaryngology consults reported from the authors' telemedicine test-bed at The New York Eye and Ear Infirmary are reported.
Abstract: This article considers both store-and-forward and interactive applications of telemedicine in otolaryngology (the branch of medicine relating to the ears, nose, and throat) and reports on our clinical findings on the accuracy of tele-otolaryngology consults reported from our telemedicine test-bed at The New York Eye and Ear Infirmary. We outline some potential store-and-forward applications in our field and conclude with an outlook on the potential relevance of telemedicine in the practice of otolaryngology.
TL;DR: The model can be used to determine the state of health of an individual, verify the effects of drugs, and make prognoses concerning the evolution of the patient, including correlations with clinical manifestations.
Abstract: The nonlinear dynamic model presented in this article includes most aspects known thus far regarding the dynamics of HIV-1 in the human body. It permits an analytical study of the dynamics of the disease (AIDS). The parameters used in the model can be estimated from data obtained in sequential measures taken from patients without interrupting any treatment. The model can be used to determine the state of health of an individual, verify the effects of drugs, and make prognoses concerning the evolution of the patient, including correlations with clinical manifestations.
TL;DR: The results suggest the value of using VAM to induce the relaxation response in order to reduce the symptom burden of hospitalized patients and point to an avenue of future research using careful patient selection, assignment, controls, variable dosage, and longer follow-up periods to test the durability of VAM interventions.
Abstract: This present study describes the outcome of a recreation therapy program of vibroacoustic music (VAM) offered to hospitalized patients. In order to provide patients with assistance in achieving the relaxation response, recreation therapists at a major federal research hospital created several relaxation opportunities for patients and family members. The present results suggest the value of using VAM to induce the relaxation response in order to reduce the symptom burden of hospitalized patients. These findings point to an avenue of future research using careful patient selection, assignment, controls, variable dosage, and longer follow-up periods to test the durability of VAM interventions.
TL;DR: The authors implemented sonification in their 3D EEG visualization environment to render synesthetic extension of a selected data channel or to introduce new composite parameters, which improved the ability to assess genuine dynamics of brain electrical activity and to perceive inherent spatio-temporal patterns of brain Electrical activity.
Abstract: Complex experiments require sophisticated visualization of a large number of parameters. However, physiological characteristics of human perception limit the number of visualized parameters and their dynamics. Multimodal data presentation could increase throughput, introduce new data streams, and improve temporal resolution. The future of biomedical data presentation will probably be marked with multimodal data presentation and integration of multiple diagnostic procedures. Here, the authors present sonification as a second presentation modality. During analysis, multimodal parameters must be set to maximize the distance of changes in the perceptual domain. The authors implemented sonification in their 3D EEG visualization environment to render synesthetic extension of a selected data channel or to introduce new composite parameters. Sonification improved the ability to assess genuine dynamics of brain electrical activity and to perceive inherent spatio-temporal patterns of brain electrical activity.
TL;DR: The authors used 80 healthy subjects to study the symmetry or preferred direction of electrical conduction of human meridians of acupuncture, and the data were then analyzed by paired-t and ANOVA testing procedures.
Abstract: Acupuncture meridian system theory is none of the main features of traditional Chinese medicine (TCM). The meridians are thought to be the pathways for qi (or bioenergy), which then circulates throughout the human body. They originate in the internal organs and from there travel up to the skin. Bilaterally opposite, symmetric acupunctures along the main meridians (called Great Acupuncture) and along the branching meridians (called opposite insertion) are two traditional methods of acupuncture commonly used in clinics. Symmetric acupoints are punctured opposite to the diseased or affected side. This article discusses the authors' work in which they used 80 healthy subjects to study the symmetry or preferred direction of electrical conduction of human meridians. The data were then analyzed by paired-t and ANOVA testing procedures.
TL;DR: The story of Jacques Arsenne d'Arsonval, the ingenious and creative French physician who did not practice medicine, but did practice research on a grand scale, is presented.
Abstract: Biomedical engineering is one of the newer specialities that evolved following the end of World War II. As with any emerging field, it is logical to look back to identify those who were doing what we now call biomedical engineering. In fact, there were many, and it is not possible to identify the first biomedical engineer but this is less important than discovering those who were applying the laws of physics to solve biomedical problems; Jacques Arsenne d'Arsonval (1851-1940) was one of these. He gave us the chlorided silver electrode; inductive and capacitive (dielectric) heating (diathermy), which paved the way for electrosurgery; the thermocouple (radiofrequency) ammeter; and the moving-coil galvanometer, which formed the basis for virtually all panel-type pointer meters. He was also the first to stimulate excitable tissue magnetically with eddy currents. We present the story of this ingenious and creative French physician who did not practice medicine, but did practice research on a grand scale.
TL;DR: A new method for fast and efficient positioning of single cells on ring electrodes by controlled suction through holes is reported and the microfabrication of electrode substrates with microholes and the cell positioning procedure is described.
Abstract: For cell biosensors and for studying neural networks using planar electrode substrates, a suitable technique for positioning single cells on electrodes was needed. We reported a new method for fast and efficient positioning of single cells on ring electrodes by controlled suction through holes. We described the microfabrication of electrode substrates with microholes and the cell positioning procedure. L929 cells and Neuro 2A cells could be positioned in parallel without cell damage.
TL;DR: The significance of telemedicine in changing diagnosis and treatment and the influence on patient transfers is examined and the utilization of telemedical consulting services is measured.
Abstract: Telemedicine is evolving into an important tool in delivering services to emergency departments (EDs) in rural areas. However, we do not yet know what kinds of services can be effectively delivered or the degree to which these services might be useful. In this pilot study, a high-speed, high-quality video, 24-hour ATM (asynchronous transfer mode) network linked a rural ED to an ED of a major medical center. The objective was to measure the utilization of telemedical consulting services. Specifically, this one-year study examined the significance of telemedicine in changing diagnosis and treatment and the influence on patient transfers.
TL;DR: A PC-based home monitoring system is described for improved management of lung transplant and asthmatic cases and its application in clinical practice is described.
Abstract: A PC-based home monitoring system is described for improved management of lung transplant and asthmatic cases.
TL;DR: The chaotic dynamic attractors expressed in the phase space are reconstructed and their correlation dimensions are calculated, which are a measure of the complexity.
Abstract: We analyze the EEG background activities of five epileptic patients and compare them with the EEGs of five control subjects by means of methods from nonlinear dynamical system theory. We divided the EEG time-series data into frames to select those that fulfilled the stationarity condition, which is necessary in order to apply our methods. Then, we reconstructed the chaotic dynamic attractors expressed in the phase space and calculated their correlation dimensions, which are a measure of the complexity. Furthermore, we recorded an EEG during a petit mal epileptic seizure, whose attractor is a 3-D plot and the correlation dimension will also be presented.