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Full-Text Articles in Biomedical Engineering and Bioengineering

Eeg Characterization Of Sensorimotor Networks: Implications In Stroke, Dylan Blake Snyder Apr 2020

Eeg Characterization Of Sensorimotor Networks: Implications In Stroke, Dylan Blake Snyder

Dissertations (1934 -)

The purpose of this dissertation was to use electroencephalography (EEG) to characterize sensorimotor networks and examine the effects of stroke on sensorimotor networks. Sensorimotor networks play an essential role in completion of everyday tasks, and when damaged, as in stroke survivors, the successful completion of seemingly simple motor tasks becomes fantasy. When sensorimotor networks are impaired as a result of stroke, varying degrees of sensorimotor deficits emerge, most often including loss of sensation and difficulty generating upper extremity movements. Although sensory therapies, such as the application of tendon vibration, have been shown to reduce the sensorimotor deficits after stroke, the ...


Indirect Structural Connectivity As A Biomarker For Stroke Motor Recovery, Miguel Renato Sotelo Munoz Apr 2020

Indirect Structural Connectivity As A Biomarker For Stroke Motor Recovery, Miguel Renato Sotelo Munoz

Dissertations (1934 -)

In this dissertation project, we demonstrated that diffusion magnetic resonance imaging and measures of indirect structural brain connectivity are sensitive to changes in fiber integrity and connectivity to remote regions in the brain after stroke. Our results revealed new insights into the effects local lesions have on global connectivity—in particular, the cerebellum—and how these changes in connectivity and integrity relate to motor impairment. We tested this methodology on two stroke groups—subacute and chronic—and were able to show that indirect connectivity is sensitive to differences in connectivity during stroke recovery. Our work can inform clinical methods for ...


Reaching Performance In Heathy Individuals And Stroke Survivors Improves After Practice With Vibrotactile State Feedback, Valay A. Shah Apr 2020

Reaching Performance In Heathy Individuals And Stroke Survivors Improves After Practice With Vibrotactile State Feedback, Valay A. Shah

Dissertations (1934 -)

Stroke causes deficits of cognition, motor, and/or somatosensory functions. These deficits degrade the capability to perform activities of daily living (ADLs). Many research investigations have focused on mitigating the motor deficits of stroke through motor rehabilitation. However, somatosensory deficits are common and may contribute importantly to impairments in the control of functional arm movement. This dissertation advances the goal of promoting functional motor recovery after stroke by investigating the use of a vibrotactile feedback (VTF) body-machine interface (BMI). The VTF BMI is intended to improve control of the contralesional arm of stroke survivors by delivering supplemental limb-state feedback to ...


Characterization Of Neuroimage Coupling Between Eeg And Fmri Using Within-Subject Joint Independent Component Analysis, Nicholas Heugel Apr 2020

Characterization Of Neuroimage Coupling Between Eeg And Fmri Using Within-Subject Joint Independent Component Analysis, Nicholas Heugel

Dissertations (1934 -)

The purpose of this dissertation was to apply joint independent component analysis (jICA) to electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) to characterize the neuroimage coupling between the two modalities. EEG and fMRI are complimentary imaging techniques which have been used in conjunction to investigate neural activity. Understanding how these two imaging modalities relate to each other not only enables better multimodal analysis, but also has clinical implications as well. In particular, Alzheimer’s, Parkinson’s, hypertension, and ischemic stroke are all known to impact the cerebral blood flow, and by extension alter the relationship between EEG and fMRI ...


An Evaluation Of The Host Response To An Interspinous Process Device Based On A Series Of Spine Explants: Device For Intervertebral Assisted Motion (Diam®), Jeffrey M. Toth, Justin D. Bric Dec 2019

An Evaluation Of The Host Response To An Interspinous Process Device Based On A Series Of Spine Explants: Device For Intervertebral Assisted Motion (Diam®), Jeffrey M. Toth, Justin D. Bric

Biomedical Engineering Faculty Research and Publications

Background:

The objective of this study was to evaluate the host response to an interspinous process device [Device for Intervertebral Assisted Motion (DIAM®)] based on a series of nine spine explants with a mean post-operative explant time of 35 months.

Methods:

Explanted periprosthetic tissues were processed for histology and stained with H&E, Wright-Giemsa stain, and Oil Red O. Brightfield and polarized light microscopy were used to evaluate the host response to the device and the resultant particulate debris. The host response was graded per ASTM F981-04. Quantitative histomorphometry was used to characterize particle size, shape, and area per ASTM ...


Pharmacokinetics Of 99mTc-Hmpao In Isolated Perfused Rat Lungs, Anne V. Clough, Katherine Barry, Benjamin Michael Rizzo, Elizabeth R. Jacobs, Said H. Audi Nov 2019

Pharmacokinetics Of 99mTc-Hmpao In Isolated Perfused Rat Lungs, Anne V. Clough, Katherine Barry, Benjamin Michael Rizzo, Elizabeth R. Jacobs, Said H. Audi

Biomedical Engineering Faculty Research and Publications

Lung uptake of technetium-labeled hexamethylpropyleneamine oxime (HMPAO) increases in rat models of human acute lung injury, consistent with increases in lung tissue glutathione (GSH). Since 99mTc-HMPAO uptake is the net result of multiple cellular and vascular processes, the objective was to develop an approach to investigate the pharmacokinetics of 99mTc-HMPAO uptake in isolated perfused rat lungs. Lungs of anesthetized rats were excised and connected to a ventilation-perfusion system. 99mTc-HMPAO (56 MBq) was injected into the pulmonary arterial cannula, a time sequence of images was acquired, and lung time-activity curves were constructed. Imaging was repeated with a range ...


Role Of The Cortex In Visuomotor Control Of Arm Stability, Dylan B. Snyder, Scott A. Beardsley, Brian D. Schmit Nov 2019

Role Of The Cortex In Visuomotor Control Of Arm Stability, Dylan B. Snyder, Scott A. Beardsley, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

Whereas numerous motor control theories describe the control of arm trajectory during reach, the control of stabilization in a constant arm position (i.e., visuomotor control of arm posture) is less clear. Three potential mechanisms have been proposed for visuomotor control of arm posture: 1) increased impedance of the arm through co-contraction of antagonistic muscles, 2) corrective muscle activity via spinal/supraspinal reflex circuits, and/or 3) intermittent voluntary corrections to errors in position. We examined the cortical mechanisms of visuomotor control of arm posture and tested the hypothesis that cortical error networks contribute to arm stabilization. We collected electroencephalography ...


Vibration Propagation On The Skin Of The Arm, Valay A. Shah, Maura Casadio, Robert A. Scheidt, Leigh A. Mrotek Oct 2019

Vibration Propagation On The Skin Of The Arm, Valay A. Shah, Maura Casadio, Robert A. Scheidt, Leigh A. Mrotek

Biomedical Engineering Faculty Research and Publications

Vibrotactile interfaces are an inexpensive and non-invasive way to provide performance feedback to body-machine interface users. Interfaces for the upper extremity have utilized a multi-channel approach using an array of vibration motors placed on the upper extremity. However, for successful perception of multi-channel vibrotactile feedback on the arm, we need to account for vibration propagation across the skin. If two stimuli are delivered within a small distance, mechanical propagation of vibration can lead to inaccurate perception of the distinct vibrotactile stimuli. This study sought to characterize vibration propagation across the hairy skin of the forearm. We characterized vibration propagation by ...


Differential Cortical Activation During The Perception Of Moving Objects Along Different Trajectories, Finnegan J. Calabro, Scott A. Beardsley, Lucia M. Vaina Oct 2019

Differential Cortical Activation During The Perception Of Moving Objects Along Different Trajectories, Finnegan J. Calabro, Scott A. Beardsley, Lucia M. Vaina

Biomedical Engineering Faculty Research and Publications

Detection of 3D object-motion trajectories depends on the integration of two distinct visual cues: translational displacement and looming. Electrophysiological studies have identified distinct neuronal populations, whose activity depends on the precise motion cues present in the stimulus. This distinction, however, has been less clear in humans, and it is confounded by differences in the behavioral task being performed. We analyzed whole-brain fMRI, while subjects performed a common time-to-arrival task for objects moving along three trajectories: moving directly towards the observer (collision course), with trajectories parallel to the line of sight (passage course), and with trajectories perpendicular to the line of ...


Exercise-Induced Alterations In Sympathetic-Somatomotor Coupling In Incomplete Spinal Cord Injury, Tanya Onushko, Gordhan B. Mahtani, Gabrielle Brazg, T. George Hornby, Brian D. Schmit Aug 2019

Exercise-Induced Alterations In Sympathetic-Somatomotor Coupling In Incomplete Spinal Cord Injury, Tanya Onushko, Gordhan B. Mahtani, Gabrielle Brazg, T. George Hornby, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

The aim of this study was to understand how high- and low-intensity locomotor training (LT) affects sympathetic-somatomotor (SS) coupling in people with incomplete spinal cord injury (SCI). Proper coupling between sympathetic and somatomotor systems allows controlled regulation of cardiovascular responses to exercise. In people with SCI, altered connectivity between descending pathways and spinal segments impairs sympathetic and somatomotor coordination, which may have deleterious effects during exercise and limit rehabilitation outcomes. We postulated that high-intensity LT, which repeatedly engages SS systems, would alter SS coupling. Thirteen individuals (50 ± 7.2 years) with motor incomplete spinal cord injuries (American Spinal Injury Association ...


Supplemental Vibrotactile Feedback Of Real-Time Limb Position Enhances Precision Of Goal-Directed Reaching, Nicoletta Risi, Valay Shah, Leigh A. Mrotek, Maura Casadio, Robert A. Scheidt Jul 2019

Supplemental Vibrotactile Feedback Of Real-Time Limb Position Enhances Precision Of Goal-Directed Reaching, Nicoletta Risi, Valay Shah, Leigh A. Mrotek, Maura Casadio, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

We examined vibrotactile stimulation as a form of supplemental limb state feedback to enhance planning and ongoing control of goal-directed movements. Subjects wore a two-dimensional vibrotactile display on their nondominant arm while performing horizontal planar reaching with the dominant arm. The vibrotactile display provided feedback of hand position such that small hand displacements were more easily discriminable using vibrotactile feedback than with intrinsic proprioceptive feedback. When subjects relied solely on proprioception to capture visuospatial targets, performance was degraded by proprioceptive drift and an expansion of task space. By contrast, reach accuracy was enhanced immediately when subjects were provided vibrotactile feedback ...


Computational Characterization Of The Cellular Origins Of Electroencephalography, Shane Hesprich Apr 2019

Computational Characterization Of The Cellular Origins Of Electroencephalography, Shane Hesprich

Master's Theses (2009 -)

Electroencephalography (EEG) is a non-invasive technique used to measure brain activity. Despite its near ubiquitous presence in neuroscience, very little research has gone into connecting the electrical potentials it measures on the scalp to the underlying network activity which generates those signals. This results in most EEG analyses being more macroscopically focused (e.g. coherence and correlation analyses). Despite the many uses of macroscopically focuses analyses, limiting research to only these analyses neglects the insights which can be gained from studying network and microcircuit architecture. The ability to study these things through non-invasive techniques like EEG depends upon the ability ...


Kinematic Foot Types In Youth With Pes Planovalgus Secondary To Cerebral Palsy, Juliet Amene, Joseph J. Krzak, Karen M. Kruger, Logan Killen, Haluk Altiok, Peter A. Smith, Gerald F. Harris Feb 2019

Kinematic Foot Types In Youth With Pes Planovalgus Secondary To Cerebral Palsy, Juliet Amene, Joseph J. Krzak, Karen M. Kruger, Logan Killen, Haluk Altiok, Peter A. Smith, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Background

Kinematic variability of the foot and ankle segments exists during ambulation among individuals with pes planovalgus (PPV) secondary to cerebral palsy (CP). Clinicians have previously recognized such variability through classification schemes to identify subgroups of individuals, but have been unable to identify kinematic foot types.

Research question

The purpose of this work was to identify kinematic foot types among children with PPV secondary to CP using 3-dimensional multi-segment foot and ankle kinematics during gait as inputs for principal component analysis (PCA) and K-means cluster analysis.

Methods

In a single assessment session, multi-segment foot and ankle kinematics using the ...


A Fast, Linear Boltzmann Transport Equation Solver For Computed Tomography Dose Calculation (Acuros Ctd), Adam Wang, Alexander Maslowski, Todd Wareing, Josh Star-Lack, Taly Gilat-Schmidt Feb 2019

A Fast, Linear Boltzmann Transport Equation Solver For Computed Tomography Dose Calculation (Acuros Ctd), Adam Wang, Alexander Maslowski, Todd Wareing, Josh Star-Lack, Taly Gilat-Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose

To improve dose reporting of CT scans, patient‐specific organ doses are highly desired. However, estimating the dose distribution in a fast and accurate manner remains challenging, despite advances in Monte Carlo methods. In this work, we present an alternative method that deterministically solves the linear Boltzmann transport equation (LBTE), which governs the behavior of x‐ray photon transport through an object.

Methods

Our deterministic solver for CT dose (Acuros CTD) is based on the same approach used to estimate scatter in projection images of a CT scan (Acuros CTS). A deterministic method is used to compute photon fluence ...


Prefrontal-Accumbens Opioid Plasticity: Implications For Relapse And Dependence, Matthew Hearing Jan 2019

Prefrontal-Accumbens Opioid Plasticity: Implications For Relapse And Dependence, Matthew Hearing

Biomedical Engineering Faculty Research and Publications

In addiction, an individual’s ability to inhibit drug seeking and drug taking is thought to reflect a pathological strengthening of drug-seeking behaviors or impairments in the capacity to control maladaptive behavior. These processes are not mutually exclusive and reflect drug-induced modifications within prefrontal cortical and nucleus accumbens circuits, however unlike psychostimulants such as cocaine, far less is known about the temporal, anatomical, and cellular dynamics of these changes. We discuss what is known regarding opioid-induced adaptations in intrinsic membrane physiology and pre-/postsynaptic neurotransmission in principle pyramidal and medium spiny neurons in the medial prefrontal cortex and nucleus accumbens ...


Spatial And Temporal Influences On Discrimination Of Vibrotactile Stimuli On The Arm, Valay Shah, Maura Casadio, Robert A. Scheidt, Leigh A. Mrotek Jan 2019

Spatial And Temporal Influences On Discrimination Of Vibrotactile Stimuli On The Arm, Valay Shah, Maura Casadio, Robert A. Scheidt, Leigh A. Mrotek

Biomedical Engineering Faculty Research and Publications

Body–machine interfaces (BMIs) provide a non-invasive way to control devices. Vibrotactile stimulation has been used by BMIs to provide performance feedback to the user, thereby reducing visual demands. To advance the goal of developing a compact, multivariate vibrotactile display for BMIs, we performed two psychophysical experiments to determine the acuity of vibrotactile perception across the arm. The first experiment assessed vibration intensity discrimination of sequentially presented stimuli within four dermatomes of the arm (C5, C7, C8, and T1) and on the ulnar head. The second experiment compared vibration intensity discrimination when pairs of vibrotactile stimuli were presented simultaneously vs ...


Estimating The Spectrum In Computed Tomography Via Kullback–Leibler Divergence Constrained Optimization, Wooseok Ha, Emil Y. Sidky, Rina Foygel Barber, Taly Gilat Schmidt, Xiaochuan Pan Jan 2019

Estimating The Spectrum In Computed Tomography Via Kullback–Leibler Divergence Constrained Optimization, Wooseok Ha, Emil Y. Sidky, Rina Foygel Barber, Taly Gilat Schmidt, Xiaochuan Pan

Biomedical Engineering Faculty Research and Publications

Purpose

We study the problem of spectrum estimation from transmission data of a known phantom. The goal is to reconstruct an x‐ray spectrum that can accurately model the x‐ray transmission curves and reflects a realistic shape of the typical energy spectra of the CT system.

Methods

Spectrum estimation is posed as an optimization problem with x‐ray spectrum as unknown variables, and a Kullback–Leibler (KL)‐divergence constraint is employed to incorporate prior knowledge of the spectrum and enhance numerical stability of the estimation process. The formulated constrained optimization problem is convex and can be solved efficiently by ...


Ct Automated Exposure Control Using A Generalized Detectability Index, P. Khobragade, Franco Rupcich, Jiahua Fan, Dominic J. Crotty, Naveen M. Kulkarni, Stacy D. O'Connor, W. Dennis Foley, Taly Gilat Schmidt Jan 2019

Ct Automated Exposure Control Using A Generalized Detectability Index, P. Khobragade, Franco Rupcich, Jiahua Fan, Dominic J. Crotty, Naveen M. Kulkarni, Stacy D. O'Connor, W. Dennis Foley, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose

Identifying an appropriate tube current setting can be challenging when using iterative reconstruction due to the varying relationship between spatial resolution, contrast, noise, and dose across different algorithms. This study developed and investigated the application of a generalized detectability index (d'gen) to determine the noise parameter to input to existing automated exposure control (AEC) systems to provide consistent image quality (IQ) across different reconstruction approaches.

Methods

This study proposes a task‐based automated exposure control (AEC) method using a generalized detectability index (d'gen). The proposed method leverages existing AEC methods that are based on a prescribed noise ...


Attitudes Toward Failure In Capstone Design Projects, Jay R. Goldberg Jan 2019

Attitudes Toward Failure In Capstone Design Projects, Jay R. Goldberg

Biomedical Engineering Faculty Research and Publications

While working in industry during the 1980s and 1990s, project failures were to be avoided at all costs. For engineers in the medical device industry, these failures could be in the form of: 1) an idea for a new product or feature that eventually failed due to technical infeasibility, regulatory hurdles, lack of market interest, or difficulty in manufacturing; 2) a prototype that did not function as required; or 3) an animal or human clinical study that yielded poor results. They typically resulted in significant project delays, wasted time and money, and lost revenues, and often led to lower raises ...


Automated Quantification And Evaluation Of Motion Artifact On Coronary Ct Angiography Images, Hongfeng Ma, Eric Gros, Scott G. Baginski, Zachary R. Laste, Naveen M. Kulkarni, Darin Okerlund, Taly Gilat Schmidt Dec 2018

Automated Quantification And Evaluation Of Motion Artifact On Coronary Ct Angiography Images, Hongfeng Ma, Eric Gros, Scott G. Baginski, Zachary R. Laste, Naveen M. Kulkarni, Darin Okerlund, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Abstract

Purpose

This study developed and validated a Motion Artifact Quantification algorithm to automatically quantify the severity of motion artifacts on coronary computed tomography angiography (CCTA) images. The algorithm was then used to develop a Motion IQ Decision method to automatically identify whether a CCTA dataset is of sufficient diagnostic image quality or requires further correction.

Method

The developed Motion Artifact Quantification algorithm includes steps to identify the right coronary artery (RCA) regions of interest (ROIs), segment vessel and shading artifacts, and to calculate the motion artifact score (MAS) metric. The segmentation algorithms were verified against ground‐truth manual segmentations ...


Assessment Of A Markerless Motion Analysis System For Manual Wheelchair Application, Jacob Rammer, Brooke A. Slavens, Joseph Krzak, Jack M. Winters, Susan A. Riedel, Gerald F. Harris Nov 2018

Assessment Of A Markerless Motion Analysis System For Manual Wheelchair Application, Jacob Rammer, Brooke A. Slavens, Joseph Krzak, Jack M. Winters, Susan A. Riedel, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Background

Wheelchair biomechanics research advances accessibility and clinical care for manual wheelchair users. Standardized outcome assessments are vital tools for tracking progress, but there is a strong need for more quantitative methods. A system offering kinematic, quantitative detection, with the ease of use of a standardized outcome assessment, would be optimal for repeated, longitudinal assessment of manual wheelchair users’ therapeutic progress, but has yet to be offered.

Results

This work evaluates a markerless motion analysis system for manual wheelchair mobility in clinical, community, and home settings. This system includes Microsoft® Kinect® 2.0 sensors, OpenSim musculoskeletal modeling, and an automated ...


Detection Of Hydrogen Peroxide Production In The Isolated Rat Lung Using Amplex Red, Said H. Audi, Nina Friedly, Ranjan K. Dash, Andreas M. Beyer, Anne V. Clough, Elizabeth R. Jacobs Sep 2018

Detection Of Hydrogen Peroxide Production In The Isolated Rat Lung Using Amplex Red, Said H. Audi, Nina Friedly, Ranjan K. Dash, Andreas M. Beyer, Anne V. Clough, Elizabeth R. Jacobs

Biomedical Engineering Faculty Research and Publications

The objectives of this study were to develop a robust protocol to measure the rate of hydrogen peroxide (H2O2) production in isolated perfused rat lungs, as an index of oxidative stress, and to determine the cellular sources of the measured H2O2 using the extracellular probe Amplex red (AR). AR was added to the recirculating perfusate in an isolated perfused rat lung. AR’s highly fluorescent oxidation product resorufin was measured in the perfusate. Experiments were carried out without and with rotenone (complex I inhibitor), thenoyltrifluoroacetone (complex II inhibitor), antimycin A (complex III inhibitor), potassium ...


Early Term Effects Of Rhbmp-2 On Pedicle Screw Fixation In A Sheep Model: Histomorphometric And Biomechanical Analyses, Jeffrey M. Toth, Mei Wang, Chetan Patel, Akshi Arora Sep 2018

Early Term Effects Of Rhbmp-2 On Pedicle Screw Fixation In A Sheep Model: Histomorphometric And Biomechanical Analyses, Jeffrey M. Toth, Mei Wang, Chetan Patel, Akshi Arora

Biomedical Engineering Faculty Research and Publications

Background: The effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) on pedicle screw pullout force and its potential to improve spinal fixation have not previously been investigated. rhBMP-2 on an absorbable collagen sponge (ACS) carrier was delivered in and around cannulated and fenestrated pedicle screws in a sheep lumbar spine instability model. Two control groups (empty screw and ACS with buffer) were also evaluated. We hypothesized that rhBMP-2 could stimulate bone growth in and around the cannulated and fenestrated pedicle screws to improve early bone purchase.

Methods: Eight skeletally mature sheep underwent destabilizing laminectomies at L2–L3 and L4–L5 ...


Technical Note: Enhancing Soft Tissue Contrast And Radiation‐Induced Image Changes With Dual‐Energy Ct For Radiation Therapy, George Noid, An Tai, Diane Schott, Nilesh Mistry, Yu Liu, Taly Gilat Schmidt, Jared R. Robbins, X. Allen Li Sep 2018

Technical Note: Enhancing Soft Tissue Contrast And Radiation‐Induced Image Changes With Dual‐Energy Ct For Radiation Therapy, George Noid, An Tai, Diane Schott, Nilesh Mistry, Yu Liu, Taly Gilat Schmidt, Jared R. Robbins, X. Allen Li

Biomedical Engineering Faculty Research and Publications

Purpose

The purpose of this work is to investigate the use of low‐energy monoenergetic decompositions obtained from dual‐energy CT (DECT) to enhance image contrast and the detection of radiation‐induced changes of CT textures in pancreatic cancer.

Methods

The DECT data acquired for 10 consecutive pancreatic cancer patients during routine nongated CT‐guided radiation therapy (RT) using an in‐room CT (Definition AS Open, Siemens Healthcare, Malvern, PA) were analyzed. With a sequential DE protocol, the scanner rapidly performs two helical acquisitions, the first at a tube voltage of 80 kVp and the second at a tube voltage ...


Application Of Fractal Dimension For Quantifying Noise Texture In Computed Tomography Images, P. Khobragade, Jiahua Fan, Franco Rupcich, Dominic J. Crotty, Taly Gilat Schmidt Aug 2018

Application Of Fractal Dimension For Quantifying Noise Texture In Computed Tomography Images, P. Khobragade, Jiahua Fan, Franco Rupcich, Dominic J. Crotty, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose

Evaluation of noise texture information in CT images is important for assessing image quality. Noise texture is often quantified by the noise power spectrum (NPS), which requires numerous image realizations to estimate. This study evaluated fractal dimension for quantifying noise texture as a scalar metric that can potentially be estimated using one image realization.

Methods

The American College of Radiology CT accreditation phantom (ACR) was scanned on a clinical scanner (Discovery CT750, GE Healthcare) at 120 kV and 25 and 90 mAs. Images were reconstructed using filtered back projection (FBP/ASIR 0%) with varying reconstruction kernels: Soft, Standard, Detail ...


Will The Real Designer Please Stand Up? [Senior Design], Jay R. Goldberg Jul 2018

Will The Real Designer Please Stand Up? [Senior Design], Jay R. Goldberg

Biomedical Engineering Faculty Research and Publications

In the 1950s and 1960s, there was a popular television show called To Tell the Truth, on which three contestants claimed to be a person with an unusual occupation or distinction. Two of them were impostors, and the other was telling the truth. Four panelists asked the contestants questions to determine who was being truthful. After each panelist chose the contestant he or she thought was telling the truth, the host would ask "Will the real _____ please stand up?" To create drama, each contestant would rise at different times and then sit, leaving the contestant with the unusual occupation ...


Effects Of Spinal Fusion For Idiopathic Scoliosis On Lower Body Kinematics During Gait, Karen M. Kruger, Christina R. Garman, Joseph J. Krzak, Adam Graf, Sahar Hassani, Sergey Tarima, Peter F. Sturm, Kim W. Hammerberg, Purnendu Gupta, Gerald F. Harris Jul 2018

Effects Of Spinal Fusion For Idiopathic Scoliosis On Lower Body Kinematics During Gait, Karen M. Kruger, Christina R. Garman, Joseph J. Krzak, Adam Graf, Sahar Hassani, Sergey Tarima, Peter F. Sturm, Kim W. Hammerberg, Purnendu Gupta, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Objectives

The purpose of this study was to compare gait among patients with scoliosis undergoing posterior spinal fusion and instrumentation (PSFI) to typically developing subjects and determine if the location of the lowest instrumented vertebra impacted results.

Summary of Background Data

PSFI is the standard of care for correcting spine deformities, allowing the preservation of body equilibrium while maintaining as many mobile spinal segments as possible. The effect of surgery on joint motion distal to the spine must also be considered. Very few studies have addressed the effect of PSFI on activities such as walking and even fewer address how ...


Control Design And Implementation Of An Active Transtibial Prosthesis, Joseph Klein Jul 2018

Control Design And Implementation Of An Active Transtibial Prosthesis, Joseph Klein

Master's Theses (2009 -)

Prior work at Marquette University developed the Marquette Prosthesis, an active transtibial prosthesis that utilized a torsional spring and a four-bar mechanism. The controls for the Marquette Prosthesis implemented a finite state control algorithm to determine the state of gait of the amputee along with two lower level controllers, a PI moment controller to control the moment during stance and a PID position controller to control the position during stance. The Marquette Prosthesis was successful in mimicking the gait profile presented by Winter. However, after completing human subject testing, the Marquette Prosthesis was insufficient in trying to match the gait ...


A Biomechanical Simulation Of Musculoskeletal Kinematics During Ambulation, Alex Thomas Jul 2018

A Biomechanical Simulation Of Musculoskeletal Kinematics During Ambulation, Alex Thomas

Master's Theses (2009 -)

The purpose of this study was to validate a 3D musculoskeletal model in OpenSim and assess OpenSim’s ability to determine muscle-length variation during ambulation. An 18 camera motion capture system was used to analyze 20 healthy individuals between the ages of 18 and 35. Following data collection, the data was processed through OpenSim and Visual3D. The kinematic output processed through the OpenSim model was then compared to the kinematic output of the validated Visual3D model to validate the OpenSim model. Muscle fiber length data obtained from the same experimental data was compared to control data to assess OpenSim’s ...


Posterior Cervical Spine Crisscross Fixation: Biomechanical Evaluation, Joseph F. Cusick, Frank A. Pintar, Joseph S. Cheng, Jason I. Lifshutz, Narayan Yoganandan Jun 2018

Posterior Cervical Spine Crisscross Fixation: Biomechanical Evaluation, Joseph F. Cusick, Frank A. Pintar, Joseph S. Cheng, Jason I. Lifshutz, Narayan Yoganandan

Biomedical Engineering Faculty Research and Publications

Background

Biomechanical/anatomic limitations may limit the successful implantation, maintenance, and risk acceptance of posterior cervical plate/rod fixation for one stage decompression-fusion. A method of posterior fixation (crisscross) that resolves biomechanical deficiencies of previous facet wiring techniques and not reliant upon screw implantation has been devised. The biomechanical performance of the new method of facet fixation was compared to the traditional lateral mass plate/screw fixation method.

Methods

Thirteen human cadaver spine segments (C2-T1) were tested under flexion-compression loading and four were evaluated additionally under pure-moment load. Preparations were evaluated in a sequence of surgical alterations with intact, laminectomy ...