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Biomedical Engineering, IEEE Transactions on

Issue 8 • Date Aug. 2009

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Displaying Results 1 - 25 of 26
  • Table of contents

    Publication Year: 2009 , Page(s): C1
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  • IEEE Transactions on Biomedical Engineering publication information

    Publication Year: 2009 , Page(s): C2
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  • Table of contents

    Publication Year: 2009 , Page(s): 1961 - 1962
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  • An Impedance-Based Catheter Positioning System for Cardiac Mapping and Navigation

    Publication Year: 2009 , Page(s): 1963 - 1970
    Cited by:  Papers (3)  |  Patents (23)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (667 KB) |  | HTML iconHTML  

    Over the last years, nonfluoroscopic in vivo cardiac mapping and navigation systems have been developed and successfully applied in clinical electrophysiology. Clearly, a trend can be observed to introduce more sensors into the measurement system so that physiological information can be gathered simultaneously and more efficiently and the duration of procedure can be shortened significantly. However, it would not be realistic to equip each catheter electrode with a localizer, e.g., by embedding a miniature magnetic location sensor. Therefore, in this paper, an alternate approach has been worked out to efficiently localize multiple catheter electrodes by considering the impedance between electrodes in the heart and electrode patches on the body surface. In application of the new technique, no additional expensive and sophisticated hardware is required other than the currently existing cardiac navigation system. A tank model and a computerized realistic human model are employed to support the development of the positioning system. In the simulation study, the new approach achieves an average localization error of less than 1 mm, which proves the feasibility of the impedance-based catheter positioning system. Consequently, the new positioning system can provide an inexpensive and accurate solution to improve the efficiency and efficacy of catheter ablation. View full abstract»

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  • Spinal Cord Injury Detection and Monitoring Using Spectral Coherence

    Publication Year: 2009 , Page(s): 1971 - 1979
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (607 KB) |  | HTML iconHTML  

    In this paper, spectral coherence (SC) is used to study the somatosensory evoked potential (SEP) signals in rodent model before and after spinal cord injury (SCI). The SC technique is complemented with the Basso, Beattie, and Bresnahan (BBB) behavior analysis method to help us assess the status of the motor recovery. SC can be used to follow the effects of SCI without any preinjury baseline information. In this study, adult female Fischer rats received contusion injury at T8 level with varying impact heights using the standard New York University impactor. The results show that the average SC between forelimb and hindlimb SEP signals before injury was relatively high ( ges0.7). Following injury, the SC between the forelimb and hindlimb SEP signals dropped to various levels (les0.7) corresponding to the severity of SCI. The SC analysis gave normalized quantifiable results for the evaluation of SCI and recovery thereafter using the forelimb signals as an effective control, without the need of any baseline data. This technique solves the problems associated with the commonly used time-domain analysis like the need of a trained neurophysiologist to interpret the data and the need for baseline data. We believe that both SC and BBB may provide a comprehensive and complementary picture of the health status of the spinal cord after injury. The presented method is applicable to SCIs not affecting the forelimb SEP signals. View full abstract»

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  • Three-Dimensional Imaging of Complex Neural Activation in Humans From EEG

    Publication Year: 2009 , Page(s): 1980 - 1988
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (719 KB) |  | HTML iconHTML  

    Electro- or magnetoencephalography (EEG/MEG) are of utmost advantage in studying transient neuronal activity and its timing with respect to behavior in the working human brain. Direct localization of the neural substrates underlying EEG/MEG is commonly achieved by modeling neuronal activity as dipoles. However, the success of neural source localization with the dipole model has only been demonstrated in relatively simple localization tasks owing to the simplified model and its insufficiency in differentiating cortical sources with different extents. It would be of great interest to image complex neural activation with multiple sources of different cortical extensions directly from EEG/MEG. We have investigated this crucial issue by adding additional parameters to the dipole model, leading to the multipole model to better represent the extended sources confined to the convoluted cortical surface. The localization of multiple cortical sources is achieved by using the subspace source localization method with the multipole model. Its performance is evaluated with simulated data as compared with the dipole model, and further illustrated with the real data obtained during visual stimulations in human subjects. The interpretation of the localization results is fully supported by our knowledge about their anatomic locations and functional magnetic resonance imaging data in the same experimental setting. Methods for estimating multiple neuronal sources at cortical areas will facilitate our ability to characterize the cortical electrical activity from simple, early sensory components to more complex networks, such as in visual, motor, and cognitive tasks. View full abstract»

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  • Regularized Estimation of Retinal Vascular Oxygen Tension From Phosphorescence Images

    Publication Year: 2009 , Page(s): 1989 - 1995
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (373 KB) |  | HTML iconHTML  

    The level of retinal oxygenation is potentially an important cue to the onset or presence of some common retinal diseases. An improved method for assessing oxygen tension in retinal blood vessels from phosphorescence lifetime imaging data is reported in this paper. The optimum estimate for phosphorescence lifetime and oxygen tension is obtained by regularizing the least-squares (LS) method. The estimation method is implemented with an iterative algorithm to minimize a regularized LS cost function. The effectiveness of the proposed method is demonstrated by applying it to simulated data as well as image data acquired from rat retinas. The method is shown to yield estimates that are robust to noise and whose variance is lower than that obtained with the classical LS method. View full abstract»

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  • Multilead ECG Delineation Using Spatially Projected Leads From Wavelet Transform Loops

    Publication Year: 2009 , Page(s): 1996 - 2005
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (795 KB) |  | HTML iconHTML  

    In this paper, a novel multilead (ML) based automatic strategy for delineation of ECG boundaries is proposed and evaluated with respect to the QRS and T-wave boundaries. The ML strategy is designed from a single-lead (SL) wavelet-transform-based delineation system. It departs from three orthogonal leads and takes advantage of the spatial information provided using a derived lead better fitted for delineation. SL delineation is then applied over this optimal derived lead. The ML strategy produces a reduced error dispersion compared to SL results, thus providing more robust, accurate, and stable boundary locations than any electrocardiographic lead by itself and outperforming strategies based on lead selection rules after SL delineation. View full abstract»

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  • Assessment of Changes in Upper Airway Obstruction by Automatic Identification of Inspiratory Flow Limitation During Sleep

    Publication Year: 2009 , Page(s): 2006 - 2015
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (645 KB) |  | HTML iconHTML  

    New techniques for automatic invasive and noninvasive identification of inspiratory flow limitation (IFL) are presented. Data were collected from 11 patients with full nocturnal polysomnography and gold-standard esophageal pressure (Pes) measurement. A total of 38,782 breaths were extracted and automatically analyzed. An exponential model is proposed to reproduce the relationship between Pes and airflow of an inspiration and achieve an objective assessment of changes in upper airway obstruction. The characterization performance of the model is appraised with three evaluation parameters: mean-squared error when estimating resistance at peak pressure, coefficient of determination, and assessment of IFL episodes. The model's results are compared to the two best-performing models in the literature. The obtained gold-standard IFL annotations were then employed to train, test, and validate a new noninvasive automatic IFL classification system. Discriminant analysis, support vector machines, and Adaboost algorithms were employed to objectively classify breaths noninvasively with features extracted from the time and frequency domains of the breathspsila flow patterns. The results indicated that the exponential model characterizes IFL and subtle relative changes in upper airway obstruction with the highest accuracy and objectivity. The new noninvasive automatic classification system also succeeded in identifying IFL episodes, achieving a sensitivity of 0.87 and a specificity of 0.85. View full abstract»

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  • Improved Phoneme-Based Myoelectric Speech Recognition

    Publication Year: 2009 , Page(s): 2016 - 2023
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (631 KB) |  | HTML iconHTML  

    This paper introduces an enhanced phoneme-based myoelectric signal (MES) speech recognition system. The system can recognize new words without retraining the phoneme classifier, which is considered to be the main advantage of phoneme-based speech recognition. It is shown that previous systems experience severe performance degradation when new words are added to a testing dataset. To maintain high accuracy with new words, several improvements are proposed. In the proposed MES speech recognition approach, the raw MES is processed by class-specific rotation matrices to spatially decorrelate the data prior to feature extraction in a preprocessing stage. Then, an uncorrelated linear discriminant analysis is used for dimensionality reduction. The resulting data are classified through a hidden Markov model classifier to obtain the phonemic log likelihoods of the phonemes, which are mapped to corresponding words using a word classifier. An average word classification accuracy of 98.533% is achieved over six subjects. The system offers dramatically improved accuracy when expanding a vocabulary, offering promise for robust large-vocabulary myoelectric speech recognition. View full abstract»

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  • Enhanced {\mu } Rhythm Extraction Using Blind Source Separation and Wavelet Transform

    Publication Year: 2009 , Page(s): 2024 - 2034
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (713 KB) |  | HTML iconHTML  

    The mu rhythm is an electroencephalogram (EEG) signal located at the central region of the brain that is frequently used for studies concerning motor activity. Quite often, the EEG data are contaminated with artifacts and the application of blind source separation (BSS) alone is insufficient to extract the mu rhythm component. We present a new two-stage approach to extract the mu rhythm component. The first stage uses second-order blind identification (SOBI) with stationary wavelet transform (SWT) to automatically remove the artifacts. In the second stage, SOBI is applied again to find the mu rhythm component. Our method is first compared with independent component analysis with discrete wavelet transform (ICA-DWT) as well as SOBI-DWT, ICA-SWT, and regression method for artifact removal using simulated EEG data. The results showed that the regression method is more effective in removing electrooculogram (EOG) artifacts, while SOBI-SWT is more effective in removing electromyogram (EMG) artifacts as compared to the other artifact removal methods. Then, all the methods are compared with the direct application of SOBI in extracting mu rhythm components on simulated and actual EEG data from ten subjects. The results showed that the proposed method of SOBI-SWT artifact removal enhances the extraction of the mu rhythm component. View full abstract»

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  • xDAWN Algorithm to Enhance Evoked Potentials: Application to Brain–Computer Interface

    Publication Year: 2009 , Page(s): 2035 - 2043
    Cited by:  Papers (39)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (836 KB) |  | HTML iconHTML  

    A brain-computer interface (BCI) is a communication system that allows to control a computer or any other device thanks to the brain activity. The BCI described in this paper is based on the P300 speller BCI paradigm introduced by Farwell and Donchin. An unsupervised algorithm is proposed to enhance P300 evoked potentials by estimating spatial filters; the raw EEG signals are then projected into the estimated signal subspace. Data recorded on three subjects were used to evaluate the proposed method. The results, which are presented using a Bayesian linear discriminant analysis classifier, show that the proposed method is efficient and accurate. View full abstract»

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  • Electrical Conductivity and Permittivity of Murine Myocardium

    Publication Year: 2009 , Page(s): 2044 - 2053
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (677 KB) |  | HTML iconHTML  

    A classic problem in traditional conductance measurement of left ventricular (LV) volume is the separation of the contributions of myocardium from blood. Measurement of both the magnitude and the phase of admittance allow estimation of the time-varying myocardial contribution, which provides a substantial improvement by eliminating the need for hypertonic saline injection. We present in vivo epicardial surface probe measurements of electrical properties in murine myocardium using two different techniques (a digital and an analog approach). These methods exploit the capacitive properties of the myocardium, and both methods yield similar results. The relative permittivity varies from approximately 100 000 at 2 kHz to approximately 5000 at 50 kHz. The electrical conductivity is approximately constant at 0.16 S/m over the same frequency range. These values can be used to estimate and eliminate the time-varying myocardial contribution from the combined signal obtained in LV conductance catheter measurements, thus yielding the blood contribution alone. To study the effects of albumin on the blood conductivity, we also present electrical conductivity estimates of murine blood with and without typical administrations of albumin during the experiment. The blood conductivity is significantly altered (p < 0.0001) by administering albumin (0.941 S/m with albumin, 0.478 S/m without albumin). View full abstract»

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  • Estimation of Respiratory Rate From Photoplethysmogram Data Using Time–Frequency Spectral Estimation

    Publication Year: 2009 , Page(s): 2054 - 2063
    Cited by:  Papers (26)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (437 KB) |  | HTML iconHTML  

    We present a new method that uses the pulse oximeter signal to estimate the respiratory rate. The method uses a recently developed time-frequency spectral estimation method, variable-frequency complex demodulation (VFCDM), to identify frequency modulation (FM) of the photoplethysmogram waveform. This FM has a measurable periodicity, which provides an estimate of the respiration period. We compared the performance of VFCDM to the continuous wavelet transform (CWT) and autoregressive (AR) model approaches. The CWT method also utilizes the respiratory sinus arrhythmia effect as represented by either FM or AM to estimate respiratory rates. Both CWT and AR model methods have been previously shown to provide reasonably good estimates of breathing rates that are in the normal range (12-26 breaths/min). However, to our knowledge, breathing rates higher than 26 breaths/min and the real-time performance of these algorithms are yet to be tested. Our analysis based on 15 healthy subjects reveals that the VFCDM method provides the best results in terms of accuracy (smaller median error), consistency (smaller interquartile range of the median value), and computational efficiency (less than 0.3 s on 1 min of data using a MATLAB implementation) to extract breathing rates that varied from 12-36 breaths/min. View full abstract»

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  • Development of an Autonomous Biological Cell Manipulator With Single-Cell Electroporation and Visual Servoing Capabilities

    Publication Year: 2009 , Page(s): 2064 - 2074
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (546 KB) |  | HTML iconHTML  

    Studies of single cells via microscopy and microinjection are a key component in research on gene functions, cancer, stem cells, and reproductive technology. As biomedical experiments become more complex, there is an urgent need to use robotic systems to improve cell manipulation and microinjection processes. Automation of these tasks using machine vision and visual servoing creates significant benefits for biomedical laboratories, including repeatability of experiments, higher throughput, and improved cell viability. This paper presents the development of a new 5-DOF robotic manipulator, designed for manipulating and microinjecting single cells. This biological cell manipulator (BCM) is capable of autonomous scanning of a cell culture followed by autonomous injection of cells using single-cell electroporation (SCE). SCE does not require piercing the cell membrane, thereby keeping the cell membrane fully intact. The BCM features high-precision 3-DOF translational and 2-DOF rotational motion, and a second z-axis allowing top-down placement of a micropipette tip onto the cell membrane for SCE. As a technical demonstration, the autonomous visual servoing and microinjection capabilities of the single-cell manipulator are experimentally shown using sea urchin eggs. View full abstract»

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  • Transabdominal Fetal Heart Rate Detection Using NIR Photopleythysmography: Instrumentation and Clinical Results

    Publication Year: 2009 , Page(s): 2075 - 2082
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1077 KB) |  | HTML iconHTML  

    In obstetrics, fetal heart rate (FHR) detection remains the standard for intrapartum assessment of fetal well-being. In this paper, a low-power (<55 mW) optical technique is proposed for transabdominal FHR detection using near-infrared photoplesthysmography (PPG). A beam of IR-LED (890 nm) propagates through to the maternal abdomen and fetal tissues, resulting in a mixed signal detected by a low-noise detector situated at a distance of 4 cm. Low-noise amplification and 24-bit analog-to-digital converter resolution ensure minimum effect of quantization noise. After synchronous detection, the mixed signal is processed by an adaptive filter to extract the fetal signal, whereas the PPG from the mother's index finger is the reference input. A total of 24 datasets were acquired from six subjects at 37 plusmn 2 gestational weeks. Results show a correlation coefficient of 0.96 (p-value < 0.001) between the proposed optical and ultrasound FHR, with a maximum error of 4%. Assessment of the effect of probe position on detection accuracy indicates that the probe should be close to fetal tissues, but not necessarily restricted to head or buttocks. View full abstract»

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  • Effects of Dielectric Parameters of Human Body on Radiation Characteristics of Ingestible Wireless Device at Operating Frequency of 430 MHz

    Publication Year: 2009 , Page(s): 2083 - 2094
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1541 KB) |  | HTML iconHTML  

    In order to assess the sensitivities of the radiation characteristics and the compliance of ingestible wireless device (IWD) in human body due to the uncertainty and intersubject variability of dielectric properties of human body tissues, the specific absorption rate (SAR) and radiation characteristics of the IWD in two realistic human body models with changed and unchanged dielectric values are quantitatively compared using the finite-difference time-domain method. Simulations are carried out in 13 scenarios where the IWD is placed in the center positions of abdomens in the two body models at the operating frequency of 430 MHz with three orientations. Results show that the variation of radiation intensity near the surface of abdomen is around 2.5 dB within 20% variation of dielectric values. The maximum SAR values increase with the increase in conductivities of human body tissues and decrease with the increase in relative permittivities of human body tissues. A variation of up to 20% in conductivities and relative permittivities, alone or simultaneously, always causes a variation of SAR to be less than 10%. As far as the compliance of safety is concerned, the maxima of 1-g-averaged and 10-g-averaged SARs can reach 3.16 and 0.89 W/kg at the input power of 25 mW. View full abstract»

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  • Extraction of Bistable-Percept-Related Features From Local Field Potential by Integration of Local Regression and Common Spatial Patterns

    Publication Year: 2009 , Page(s): 2095 - 2103
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (736 KB) |  | HTML iconHTML  

    Bistable perception arises when an ambiguous stimulus under continuous view is perceived as an alternation of two mutually exclusive states. Such a stimulus provides a unique opportunity for understanding the neural basis of visual perception because it dissociates the perception from the visual input. In this paper, we focus on extracting the percept-related features from the local field potential (LFP) in monkey visual cortex for decoding its bistable structure-from-motion (SFM) perception. Our proposed feature extraction approach consists of two stages. First, we estimate and remove from each LFP trial the nonpercept-related stimulus-evoked activity via a local regression method called the locally weighted scatterplot smoothing because of the dissociation between the perception and the stimulus in our experimental paradigm. Second, we use the common spatial patterns approach to design spatial filters based on the residue signals of multiple channels to extract the percept-related features. We exploit a support vector machine (SVM) classifier on the extracted features to decode the reported perception on a single-trial basis. We apply the proposed approach to the multichannel intracortical LFP data collected from the middle temporal (MT) visual cortex in a macaque monkey performing an SFM task. We demonstrate that our approach is effective in extracting the discriminative features of the percept-related activity from LFP and achieves excellent decoding performance. We also find that the enhanced gamma band synchronization and reduced alpha and beta band desynchronization may be the underpinnings of the percept-related activity. View full abstract»

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  • Steady-State Movement Related Potentials for Brain–Computer Interfacing

    Publication Year: 2009 , Page(s): 2104 - 2113
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (655 KB) |  | HTML iconHTML  

    An approach for brain-computer interfacing (BCI) by analysis of steady-state movement related potentials (ssMRPs) produced during rhythmic finger movements is proposed in this paper. The neurological background of ssMRPs is briefly reviewed. Averaged ssMRPs represent the development of a lateralized rhythmic potential, and the energy of the EEG signals at the finger tapping frequency can be used for single-trial ssMRP classification. The proposed ssMRP-based BCI approach is tested using the classic Fisher's linear discriminant classifier. Moreover, the influence of the current source density transform on the performance of BCI system is investigated. The averaged correct classification rates (CCRs) as well as averaged information transfer rates (ITRs) for different sliding time windows are reported. Reliable single-trial classification rates of 88%-100% accuracy are achievable at relatively high ITRs. Furthermore, we have been able to achieve CCRs of up to 93% in classification of the ssMRPs recorded during imagined rhythmic finger movements. The merit of this approach is in the application of rhythmic cues for BCI, the relatively simple recording setup, and straightforward computations that make the real-time implementations plausible. View full abstract»

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  • Mental State Estimation for Brain--Computer Interfaces

    Publication Year: 2009 , Page(s): 2114 - 2122
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (499 KB) |  | HTML iconHTML  

    Mental state estimation is potentially useful for the development of asynchronous brain-computer interfaces. In this study, four mental states have been identified and decoded from the electrocorticograms (ECoGs) of six epileptic patients, engaged in a memory reach task. A novel signal analysis technique has been applied to high-dimensional, statistically sparse ECoGs recorded by a large number of electrodes. The strength of the proposed technique lies in its ability to jointly extract spatial and temporal patterns, responsible for encoding mental state differences. As such, the technique offers a systematic way of analyzing the spatiotemporal aspects of brain information processing and may be applicable to a wide range of spatiotemporal neurophysiological signals. View full abstract»

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  • Estimation of Postaverage SNR from Evoked Responses Under Nonstationary Noise

    Publication Year: 2009 , Page(s): 2123 - 2130
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (199 KB) |  | HTML iconHTML  

    In any measure of event-related potentials, it is important to be able to estimate the postaverage signal-to-noise ratio (SNR) in order to assess the quality of the measured signals. The estimated postaverage SNR can be an important detection criteria (as in infant hearing-screening of evoked auditory potentials) and a control factor when comparing signals obtained during different conditions (accounting for residual noise variability). Standard SNR estimation methods, such as the fixed-single-point (Fsp) statistic (C. Elberling and M. Don, ldquoQuality estimation of averaged auditory brainstem responses,rdquo Scandinavian Audiol., vol. 13, pp. 187-197, 1984), assume a single-stationary noise source, with the postaverage SNR increasing proportionally to the number of trials averaged. This study proposes a modified version of the Fsp statistic, the nonstationary fixed-multiple-point (NS Fmp), that can account for a discrete number of noise sources of different power, and can also be modified for weighted averaging (WNS Fmp). A new noise segmentation procedure is also proposed that dynamically partitions contiguous trials based on their noise power estimates and a series of F-tests. Results from computer simulation and real data from auditory brain stem recordings show that the NS Fmp method yields lower mean square error than do the Fsp, and that the WNS Fmp has higher receiver-operating-curve area than do the standard Fsp procedure. View full abstract»

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  • Surface Current Density Mapping for Identification of Gastric Slow Wave Propagation

    Publication Year: 2009 , Page(s): 2131 - 2139
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (645 KB) |  | HTML iconHTML  

    The magnetogastrogram (MGG) records clinically relevant parameters of the electrical slow wave of the stomach noninvasively. Besides slow wave frequency, gastric slow wave propagation velocity is a potentially useful clinical indicator of the state of health of gastric tissue, but it is a difficult parameter to determine from noninvasive bioelectric or biomagnetic measurements. We present a method for computing the surface current density from multichannel MGG recordings that allows computation of the propagation velocity of the gastric slow wave. A moving dipole source model with hypothetical as well as realistic biomagnetometer parameters demonstrates that while a relatively sparse array of magnetometer sensors is sufficient to compute a single average propagation velocity, more detailed information about spatial variations in propagation velocity requires higher density magnetometer arrays. Finally, the method is validated with simultaneous MGG and serosal electromyography measurements in a porcine subject. View full abstract»

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  • Characterization of Catheter Dynamics During Percutaneous Transluminal Catheter Procedures

    Publication Year: 2009 , Page(s): 2140 - 2143
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (163 KB) |  | HTML iconHTML  

    Remote catheter navigation systems are being developed to reduce the occupational risk of the intervening physician. Despite the success of such systems, development has occurred with little fundamental knowledge of the catheter dynamics applied by the interventionalist. This paper characterizes the kinematics of a catheter during manipulation, the minimum applied force/torque during interventional procedures, and the maximum force/torque applied by an operator to overcome vasculature friction. Ten operators manipulated a 6F catheter inside a specialized catheter movement sensor to determine the velocities and accelerations of catheter motion. A mass-spring apparatus was constructed to measure the forces and torques required to overcome introducer sheath and vasculature friction. Results showed the catheter was manipulated at peak velocities and accelerations of (muplusmnsigma) : 360 plusmn 180 mmldrs-1 and 22200 plusmn 14000 mmldrs-2, and 19 plusmn 7 radldrs-1 and 900 plusmn 510 radldrs-2, for axial and radial directions of motion, respectively. A minimum force of 0.29 plusmn 0.06 N and a torque of 1.15 plusmn0.3 mNldrm was required to move the catheter through the introducer sheath; while the observed maximum applied torque was 15 mNldrm to overcome vasculature friction. The implications of these results for future design optimization of an intuitive remote catheter navigation system are considered. View full abstract»

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  • Call for papers ISBI 2010

    Publication Year: 2009 , Page(s): 2144
    Save to Project icon | Request Permissions | PDF file iconPDF (553 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Biomedical Engineering information for authors

    Publication Year: 2009 , Page(s): C3
    Save to Project icon | Request Permissions | PDF file iconPDF (28 KB)  
    Freely Available from IEEE

Aims & Scope

IEEE Transactions on Biomedical Engineering contains basic and applied papers dealing with biomedical engineering. Papers range from engineering development in methods and techniques with biomedical applications to experimental and clinical investigations with engineering contributions.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Bin He
Department of Biomedical Engineering