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Classification of surface electromyogram (sEMG) signal is important for various applications such as prosthetic control and human computer interface. Surface EMG provides a better insight into the strength of muscle contraction which can be used as control signal for different applications. Due to the various interference between different muscle activities, it is difficult to identify movements using...
Gait analysis is important in diagnosing and evaluating certain neurological diseases such as Parkinson's disease (PD). In this paper, we show the ability of our wireless inertial sensor system to characterize gait abnormalities in PD. We obtain physical features of pitch, roll, and yaw rotations of the foot during walking, use principal component analysis (PCA) to select features, and use the support...
Cranioplasty is a commonly performed procedure. Outcomes can be improved by the use of patient specific implants, however, high costs limit their accessibility. This paper presents a low cost alternative technique to create patient specific polymethylmethacrylate (PMMA) implants using rapid prototyped mold template. We used available patient's CT-scans, one dataset without craniotomy and one with...
Accurate estimation of the human head conductivity is important for the diagnosis and therapy of brain diseases. Induced Current - Magnetic Resonance Electrical Impedance Tomography (IC-MREIT) is a recently developed non-invasive technique for conductivity estimation. This paper presents a formulation where a low number of material parameters need to be estimated, starting from MR eddy-current field...
Here we demonstrate the mechanical robustness of microfabricated torsional magnetic actuators in withstanding the magnetic fields produced by a 7 T MRI magnet. The static and dynamic mechanical characteristics of 30 devices were quantitatively measured before and after exposure to both uniform and non-uniform magnetic fields. The results show no statistically significant change in both the static...
The chemotherapy magnetically controlled under Magnetic Resonance Imaging (MRI) is currently one of the active areas of cancer research. This paper proposes a precise model of a therapeutic microrobot magnetically steered in blood vessels. This modeling approach takes into account the non-Newtonian behavior of blood, as well as wall effect on the blood's profile and robot-to-wall interaction forces...
This session is intended to prepare current bioengineering students and post-doctoral fellows, getting them in the right shape to apply, negotiate and succeed in getting their first job in industry or academia. Tips on putting together the appropriate CV, preparing your portfolio and getting ready for the interview will be covered by the invited speakers. The panel will consist of representatives...
Cardiac action potential duration alternans is characterized by a beat-to-beat alternation in action potential waveform. Its presence has been putatively linked to the onset of lethal cardiac arrhythmias. Previous studies, which have been limited to cardiac Purkinje fibers, have shown that closed-loop alternans control techniques, which apply a succession of externally administered cycle perturbations,...
Wireless medical ultrasound streaming is considered one of the emerging application within the broadband mobile healthcare domain. These applications are considered as bandwidth demanding services that required high data rates with acceptable diagnostic quality of the transmitted medical images. In this paper, we present the performance analysis of a medical ultrasound video streaming acquired via...
The detection of body movements during MR examination could help in reducing motion artifacts or to get patient responses during functional magnetic resonance. It can be supported by a slit scanner, that combines a camera with a light stripe projector to obtain 3D coordinates of points forming the external surface of the body. In this work we propose a slit scanner prototype based on a miniaturized...
We propose a improved Gradient Vector Flow (iGVF) for active contour detection. The algorithm herein proposed allows to surpass the problems of the GVF, which occur in noisy images with cluttered background. We experimentally illustrate that the proposed modified version of the GVF algorithm has a better performance in noisy images. The main difference concerns the use of more robust and informative...
The increasing amounts of microscopy data generated in cell biology requires the development of automated tools for the quantitative analysis of images. Clumps of cells are difficult to segment due to the frequent lack of clear boundaries between cells and are often ignored, but communication between cells is an intrinsic part of the response of cells to their environment. In addition cells often...
Renal failure patients provide a good model of fluid overload with the process of hemodialysis leading to central hypovolemia. This study aims to assess if hemodialysis induces identifiable changes in ear photoplethysmographic waveform variability (PPGV). The results are based on data collected from 10 kidney failure patients undergoing regular hemodialysis; classified as either fluid removal or non-fluid...
Ratiometric Luminescent microparticle sensors have been developed for sensing biochemical targets such as glucose in interstitial fluid, enabling use of dermal implants for on-demand monitoring. For these sensor systems to be deployed in vivo, a matched optoelectronic system for interrogation of dermally-implanted sensors was previously designed, constructed, and evaluated experimentally. During evaluation...
This presentation is a report on the in situ characterization of stimulating microelectrodes in the context of multielectrode retinal prosthetic implants. The experimental system approximately replicates the geometric and electrical parameters of Second Sight® Medical Products' Argus™ II Retinal Implant. Topographic maps of electric potentials have been prepared for a 60 electrode structure in which...
F-wave persistence is a frequently reported parameter for nerve conduction studies. F-wave activities are generated through backfiring of motor neurons. F-wave persistence is designed to estimate the backfiring rate. Through computational models and probability analyses, we demonstrated that the F-wave persistence definition is deficient in providing a robust and consistent estimate of the backfiring...
This paper develops a method to determine the minimum duration interval which ensures that the process of “sorting” the extracellular action potentials recorded during that interval achieves a desired confidence level of accuracy. During the recording process, a sequential decision theory approach continually evaluates a variant of the likelihood ratio test using the model evidence of the sorting/clustering...
The acetabular cartilage is normally represented as a spherical shape in orthopedic clinic and related researches. The aim of the study was to present a new mathematic representation with better fit to the acetabular cartilage surface and to investigate the role of its shape on the hip joint contact stress. Combined with reverse engineering technique, surface-fitting algorithms and mathematical curve...
Anterior cruciate ligament (ACL) injuries have become more common in recent years as more young people participate in risky sporting activities. Most ACL injuries occur as a result of noncontact mechanisms. Previous in vitro studies of ACL strain have found significant increases in ACL strain primarily with anterior directed force on the tibia relative to the femur and with internal rotation and often...
The capacity to quantify and evaluate gait beyond the general confines of a clinical environment under effectively autonomous conditions may alleviate rampant strain on limited and highly specialized medical resources. An iPhone consists of a three dimensional accelerometer subsystem with highly robust and scalable software applications. With the synthesis of the integral iPhone features, an iPhone...
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