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This page shows you the most recent publications within this specialty of the MedWorm directory. This is page number 13.

Effects of Degree of Surgical Correction for Flatfoot Deformity in Patient-Specific Computational Models.
Abstract A cohort of adult acquired flatfoot deformity rigid-body models was developed to investigate the effects of isolated tendon transfer with successive levels of medializing calcaneal osteotomy (MCO). Following IRB approval, six diagnosed flatfoot sufferers were subjected to magnetic resonance imaging (MRI) and their scans used to derive patient-specific models. Single-leg stance was modeled, constrained solely through physiologic joint contact, passive soft-tissue tension, extrinsic muscle force, body weight, and without assumptions of idealized mechanical joints. Surgical effect was quantified using simulat...
Source: Annals of Biomedical Engineering - December 3, 2014 Category: Biomedical Engineering Authors: Spratley EM, Matheis EA, Hayes CW, Adelaar RS, Wayne JS Tags: Ann Biomed Eng Source Type: research

Engineering Complex Orthopaedic Tissues Via Strategic Biomimicry.
The objective of strategic biomimicry is to avoid over-engineering by establishing what needs to be learned from nature and defining the essential matrix characteristics that must be reproduced in scaffold design. Application of this engineering strategy for the regeneration of the most common musculoskeletal tissue units (e.g., bone-ligament-bone, muscle-tendon-bone, cartilage-bone) will be discussed in this review. It is anticipated that these exciting efforts will enable integrative and functional repair of soft tissue injuries, and moreover, lay the foundation for the development of composite tissue systems and ultimat...
Source: Annals of Biomedical Engineering - December 3, 2014 Category: Biomedical Engineering Authors: Qu D, Mosher CZ, Boushell MK, Lu HH Tags: Ann Biomed Eng Source Type: research

Challenges in the Modeling of Wound Healing Mechanisms in Soft Biological Tissues.
Abstract Numerical models have become one of the most powerful tools in biomechanics and mechanobiology allowing highly detailed simulations. One of the fields in which they have broadly evolved during the last years is in soft tissue modeling. Particularly, wound healing in the skin is one of the processes that has been approached by computational models due to the difficulty of performing experimental investigations. During the last decades wound healing simulations have evolved from numerical models which considered only a few number of variables and simple geometries to more complex approximations that take int...
Source: Annals of Biomedical Engineering - December 2, 2014 Category: Biomedical Engineering Authors: Valero C, Javierre E, García-Aznar JM, Menzel A, Gómez-Benito MJ Tags: Ann Biomed Eng Source Type: research

Evaluation of a Multiscale Modelling Methodology to Predict the Mechanical Properties of PCL/β-TCP Sintered Scaffold Materials.
Abstract A multiscale modelling methodology to predict the macroscale stiffness of selective laser sintered polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP) materials is evaluated. The relationship between a micromechanics-evaluated composite material elastic modulus (E eff) and segment grey-value (GVave) is established for a 90/10 wt% PCL/β-TCP material and compared to the previously established E eff vs. GVave relationship for a 50/50 wt% PCL/β-TCP material. The increase in E eff with GVave was found to be greater for the 90/10 wt% material than for the 50/50 wt% material. Differences in the material...
Source: Annals of Biomedical Engineering - December 2, 2014 Category: Biomedical Engineering Authors: Doyle H, Lohfeld S, McDonnell P, McHugh P Tags: Ann Biomed Eng Source Type: research

Assessment of Daily-Life Reaching Performance After Stroke.
In this study, metrics of hand movement relative to the pelvis and the sternum were estimated in 13 stroke subjects using a full body ambulatory movement analysis system, including 17 inertial sensors integrated in a body-worn suit. Results were compared with the level of arm impairment evaluated with the upper extremity part of the Fugl-Meyer Assessment scale (uFMA). Metrics of arm movement performance of the affected side, including size of work area, maximum reaching distance and movement range in vertical direction, were evaluated during a simulated daily-life task. These metrics appeared to strongly correlate with uFM...
Source: Annals of Biomedical Engineering - December 2, 2014 Category: Biomedical Engineering Authors: van Meulen FB, Reenalda J, Buurke JH, Veltink PH Tags: Ann Biomed Eng Source Type: research

A Pre-computed Brain Response Atlas for Instantaneous Strain Estimation in Contact Sports.
In this study, we present a pre-computed brain response atlas (pcBRA) to substantially increase the simulation efficiency in estimating brain strains using isolated rotational acceleration impulses parameterized with four independent variables (peak magnitude and duration, and rotational axis azimuth and elevation angles) with values determined from on-field measurements. Using randomly generated testing datasets, the partially established pcBRA achieved a 100% success rate in interpolation based on element-wise differences in accumulated peak strain ([Formula: see text]) according to a "double-10%" criterion or average re...
Source: Annals of Biomedical Engineering - December 2, 2014 Category: Biomedical Engineering Authors: Ji S, Zhao W Tags: Ann Biomed Eng Source Type: research

Emerging Trends in Heart Valve Engineering: Part II. Novel and Standard Technologies for Aortic Valve Replacement.
Abstract The engineering of technologies for heart valve replacement (i.e., heart valve engineering) is an exciting and evolving field. Since the first valve replacement, technology has progressed by leaps and bounds. Innovations emerge frequently and supply patients and physicians with new, increasingly efficacious and less invasive treatment options. As much as any other field in medicine the treatment of heart valve disease has experienced a renaissance in the last 10 years. Here we review the currently available technologies and future options in the surgical and transcatheter treatment of aortic valve disease...
Source: Annals of Biomedical Engineering - December 2, 2014 Category: Biomedical Engineering Authors: Kheradvar A, Groves EM, Goergen CJ, Alavi SH, Tranquillo R, Simmons CA, Dasi LP, Grande-Allen KJ, Mofrad MR, Falahatpisheh A, Griffith B, Baaijens F, Little SH, Canic S Tags: Ann Biomed Eng Source Type: research

Multi-frequency Rayleigh damped elastography: studies
Magnetic Resonance Elastography (MRE) quantitatively measures induced mechanical waves via phase-contrast MR imaging techniques [1,2]. Depending on the inverse problem methodology and constitutive model used, a number of parameters, describing mechanical properties of the material, can be estimated from the measured response data. Different models allow different parameters to be identified. For example, traditional linearly elastic [3–5] models can produce locally resolved maps of elasticity, also known as the stiffness or storage modulus (μR), while viscoelastic (VE) models [6–8] can provide additional information a...
Source: Medical Engineering and Physics - December 1, 2014 Category: Biomedical Engineering Authors: Andrii Y. Petrov, Paul D. Docherty, Mathieu Sellier, J. Geoffrey Chase Source Type: research

[Front cover / Table of contents]
Presents the front cover/table of contents for this issue of the periodical. (Source: IEEE Transactions on Biomedical Engineering)
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

IEEE Transactions on Biomedical Engineering publication information
Provides a listing of current staff, committee members and society officers. (Source: IEEE Transactions on Biomedical Engineering)
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Table of contents
Presents the table of contents for this issue of the periodical. (Source: IEEE Transactions on Biomedical Engineering)
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

A System for Counting Fetal and Maternal Red Blood Cells
The Kleihauer–Betke (KB) test is the standard method for quantitating fetal-maternal hemorrhage in maternal care. In hospitals, the KB test is performed by a certified technologist to count a minimum of 2000 fetal and maternal red blood cells (RBCs) on a blood smear. Manual counting suffers from inherent inconsistency and unreliability. This paper describes a system for automated counting and distinguishing fetal and maternal RBCs on clinical KB slides. A custom-adapted hardware platform is used for KB slide scanning and image capturing. Spatial-color pixel classification with spectral clustering is proposed to sepa...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

A Wavelet-Based Electrogram Onset Delineator for Automatic Ventricular Activation Mapping
Electroanatomical mapping (EAM) systems are commonly used in clinical practice for guiding catheter ablation treatments of common arrhythmias. In focal tachycardias, the ablation target is defined by locating the earliest activation area determined by the joint analysis of electrogram (EGM) signals at different sites. However, this is currently a manual time-consuming and experience-dependent task performed during the intervention and thus prone to stress-related errors. In this paper, we present an automatic delineation strategy that combines electrocardiogram (ECG) information with the wavelet decomposition of the EGM si...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

In-Flight Automatic Detection of Vigilance States Using a Single EEG Channel
Sleepiness and fatigue can reach particularly high levels during long-haul overnight flights. Under these conditions, voluntary or even involuntary sleep periods may occur, increasing the risk of accidents. The aim of this study was to assess the performance of an in-flight automatic detection system of low-vigilance states using a single electroencephalogram channel. Fourteen healthy pilots voluntarily wore a miniaturized brain electrical activity recording device during long-haul flights ($10 pm 2.0$ h, Atlantic 2 and Falcon 50 M, French naval aviation). No subject was disturbed by the equipment. Seven pilots experienced...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Developing a Stereotypical Drosophila Brain Atlas
In this study, we propose a system to construct a standardized 3D Drosophila brain atlas by integrating labeled images from different preparations. The 3D fly brain atlas consists of standardized anatomical global and local reference models, e.g., the inner and external brain surfaces and the mushroom body. The averaged global and local reference models are generated by the model averaging procedure, and then the standard Drosophila brain atlas can be compiled by transferring the averaged neuropil models into the averaged brain surface models. The main contribution and novelty of our study is to determine the average 3D br...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Core Body Temperature Control by Total Liquid Ventilation Using a Virtual Lung Temperature Sensor
This study presents the design of a virtual lung temperature sensor to control core temperature. In the first step, the virtual sensor, using expired PFC to estimate lung temperature noninvasively, was validated both in vitro and in vivo . The virtual lung temperature was then used to rapidly and automatically control core temperature. Experimentations were performed using the Inolivent-5.0 liquid ventilator with a feedback controller to modulate inspired PFC temperature thereby controlling lung temperature. The in vivo experimental protocol was conducted on seven newborn lambs instrumented with temperature sensors at the ...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Uncontrolled Manifold Analysis of Arm Joint Angle Variability During Robotic Teleoperation and Freehand Movement of Surgeons and Novices
In this study, we determine whether teleoperation of a da Vinci Si surgical system in a nonclinical task of simple planar movements changes this structure of variability in experienced surgeons and novices. To answer this question, we employ the UnControlled manifold analysis that partitions users’ joint angle variability into task-irrelevant and task-relevant manifolds. We show that experienced surgeons coordinate their joint angles to stabilize hand movements more than novices, and that the effect of teleoperation depends on experience—experts increase teleoperated stabilization relative to freehand whereas...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Automated Quantitative Analysis of Capnogram Shape for COPD–Normal and COPD–CHF Classification
We develop an approach to quantitative analysis of carbon dioxide concentration in exhaled breath, recorded as a function of time by capnography. The generated waveform—or capnogram—is currently used in clinical practice to establish the presence of respiration as well as determine respiratory rate and end-tidal CO 2 concentration. The capnogram shape also has diagnostic value, but is presently assessed qualitatively, by visual inspection. Prior approaches to quantitatively characterizing the capnogram shape have explored the correlation of various geometric parameters with pulmonary function tests. These stu...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Examination of Hand Muscle Activation and Motor Unit Indices Derived from Surface EMG in Chronic Stroke
In this study, we used muscle and motor unit indices, derived from convenient surface electromyography (EMG) measurements, for examination of paretic muscle changes post stroke. For 12 stroke subjects, compound muscle action potential and voluntary surface EMG signals were recorded from paretic and contralateral first dorsal interosseous, abductor pollicis brevis, and abductor digiti minimi muscles. Muscle activation index (AI), motor unit number index (MUNIX), and motor unit size index (MUSIX) were then calculated for each muscle. There was a significant AI reduction for all the three muscles in paretic side compared with...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

3-D Ultrasound-Guided Robotic Needle Steering in Biological Tissue
Robotic needle steering systems have the potential to greatly improve medical interventions, but they require new methods for medical image guidance. Three-dimensional (3-D) ultrasound is a widely available, low-cost imaging modality that may be used to provide real-time feedback to needle steering robots. Unfortunately, the poor visibility of steerable needles in standard grayscale ultrasound makes automatic segmentation of the needles impractical. A new imaging approach is proposed, in which high-frequency vibration of a steerable needle makes it visible in ultrasound Doppler images. Experiments demonstrate that segmenta...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

A Noncontact Capacitive Sensing System for Recognizing Locomotion Modes of Transtibial Amputees
This paper presents a noncontact capacitive sensing system (C-Sens) for locomotion mode recognition of transtibial amputees. C-Sens detects changes in physical distance between the residual limb and the prosthesis. The sensing front ends are built into the prosthetic socket without contacting the skin. This novel signal source improves the usability of locomotion mode recognition systems based on electromyography (EMG) signals and systems based on capacitance signals obtained from skin contact. To evaluate the performance of C-Sens, we carried out experiments among six transtibial amputees with varying levels of amputation...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Using Ultrasound Backscattering Signals and Nakagami Statistical Distribution to Assess Regional Cataract Hardness
This study aims to analyze the protein aggregates spatial distribution for different cataract degrees, and correlate this information with the lens acoustical parameters and by this way, assess the cataract regional hardness. Different cataract degrees were induced ex vivo in porcine lenses. A 25 MHz ultrasonic transducer was used to obtain the acoustical parameters (velocity, attenuation, and backscattering signals). B-scan and Nakagami images were constructed. Also, lenses with different cataract degrees were sliced in two regions (nucleus and cortex), for fibers and collagen detection. A significant increase with...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

High-Resolution 3-D T${{bf _1}^{bf *}}$-Mapping and Quantitative Image Analysis of GRAY ZONE in Chronic Fibrosis
The substrate of potentially lethal cardiac arrhythmias often resides in the gray zone (GZ), a mixture of viable myocytes and collagen strands found between healthy myocardium and infarct core (IC). The specific aims of this paper are to demonstrate correspondence between regions delineated in T1* (apparent T 1) maps and tissue characteristics seen in histopathology and to determine the MR imaging resolution needed to adequately identify GZ-associated substrate in chronic infarct. For this, a novel 3-D multicontrast late enhancement (MCLE) MR method was used to image ex vivo swine hearts with chronic infarction, at ...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Reducing Risks in Type 1 Diabetes Using ${cal H}_infty$ Control
A control scheme was designed in order to reduce the risks of hyperglycemia and hypoglycemia in type 1 diabetes mellitus (T1DM). This structure is composed of three main components: an $mathcal {H}_{infty }$ robust controller, an insulin feedback loop (IFL), and a safety mechanism (SM). A control-relevant model that is employed to design the robust controller is identified. The identification procedure is based on the distribution version of the UVA/Padova metabolic simulator using the simulation adult cohort. The SM prevents dangerous scenarios by acting upon a prediction of future glucose levels, and the IFL modifies the...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research

Remote Detection of Photoplethysmographic Systolic and Diastolic Peaks Using a Digital Camera
We present a new method for measuring photoplethysmogram signals remotely using ambient light and a digital camera that allows for accurate recovery of the waveform morphology (from a distance of 3 m). In particular, we show that the peak-to-peak time between the systolic peak and diastolic peak/inflection can be automatically recovered using the second-order derivative of the remotely measured waveform. We compare measurements from the face with those captured using a contact fingertip sensor and show high agreement in peak and interval timings. Furthermore, we show that results can be significantly improved using ...
Source: IEEE Transactions on Biomedical Engineering - December 1, 2014 Category: Biomedical Engineering Source Type: research