Engineering Commons^™

The Application Of Digital Volume Correlation Bone Strain Measurements In The Osteoarthritic Glenohumeral Joint, Jakub R. Targosinski

Electronic Thesis and Dissertation Repository

This thesis investigates the accuracy and precision of digital volume correlation measurements derived from micro-computed tomography imagery of interfaces in the upper extremity of clinical relevance, namely, the implant-cement-bone interface of glenoid implants used in total shoulder arthroplasties and the implant-bone interface of shoulder hemiarthroplasties. The works within derive relationships between measurement accuracy and precision and parameters of practical interest such as image quality and measurement spatial resolution. It also analyzes the effects of micro-computed tomography image artifact-inducing materials on the accuracy and precision of digital volume correlation-based measurements and the spatial relationship between distance between the artifacting material and …

A Novel Ultrasound Elastography Technique For Evaluating Tumor Response To Neoadjuvant Chemotherapy In Patients With Locally Advanced Breast Cancer, Niusha Kheirkhah

Electronic Thesis and Dissertation Repository

Breast cancer is the second most diagnosed cancer in women, estimated to affect 1 in 8 women during their lifetime. About 10% to 20% of new breast cancer cases are diagnosed with locally advanced breast cancer (LABC). LABC tumors are usually larger than 5 cm and/or attached to the skin or chest wall. It has been reported that when such cases are treated with surgery alone, metastasis and mortality rates are high, especially where skin involvement or attachment to the chest wall is extensive. As such, efficient treatment for this kind of breast cancer includes neoadjuvant chemotherapy (NAC) to shrink …

The Effects Of A Porous Internal Lattice Design On The Articular Contact Mechanics Of Radial Head Hemiarthroplasty Implants, Jessica Benitah

Electronic Thesis and Dissertation Repository

Hemiarthroplasty, where one side of a joint is replaced, is a minimally invasive procedure. It allows for the preservation of native tissue, though a significant ramification is accelerated cartilage wear when articulating with high stiffness materials that do not mimic the mechanical stiffness of the native tissue. An implant that employs a lattice design can significantly lower the stiffness of a solid structure whilst maintaining strength. This study was conducted to investigate the effect of implementing a porous internal lattice structure with a thin outer shell on the articular contact mechanics, using a radial head hemiarthroplasty. It was hypothesized that …

The Bio-Mechanical Development And Kinematic Evaluation Of Zone I And Zone Ii Injuries And Their Corresponding Surgical Repair Techniques Using An In-Vitro Active Finger Motion Simulator: A Cadaveric Study, Mohammad Haddara

Electronic Thesis and Dissertation Repository

Research development involving large scale joint mechanics and biomechanical adaptations is growing. However, interest in smaller scale joints, such as the fingers, is limited. Thus, the present work describes the enhancement and clinical application of a previously designed in-vitro active finger motion simulator in measuring and assessing intrinsic joint kinematics and tissue biomechanics including load transfer and strains induced tissues within the finger. Accuracy of electromagnetic tracking (EM) systems were evaluated compared to the standard optical tracking systems and used to develop motion derived finger joint coordinate systems. Moreover, minute strain gauges were utilized to measure strains induced by the …

Sol-Gel Derived Bioceramic Poly(Diethyl Fumarate – Co – Triethoxyvinylsilane) Composite, Aref Sleiman

Electronic Thesis and Dissertation Repository

Synthetic bone graft materials have become an increasingly popular choice for bone augmentation. Ceramic-based and polymer-based bone graft materials constitute the two main classes of synthetic bone graft materials. This study investigated the synthesis of novel bioactive composites for their potential use as bone graft biomaterials. Poly(diethyl fumarate-co-triethoxyvinylsilane)/bioceramic class II organic/inorganic hybrid biomaterials were synthesized via a sol gel process. These biomaterials were then reacted with an ammonium phosphate solution to prepare their respective composites. For the first time, we successfully synthesized sol-gel derived bioceramic poly(diethyl fumarate-co-triethoxyvinylsilane) composites. In vitro bioactivity evaluation of poly(diethyl fumarate-co-triethoxyvinylsilane)/bioceramic composites in simulated body fluid …

Cost-Effective Non-Destructive Testing Of Biomedical Components Fabricated Using Additive Manufacturing, Santiago Fabian Cobos

Electronic Thesis and Dissertation Repository

Biocompatible titanium-alloys can be used to fabricate patient-specific medical components using additive manufacturing (AM). These novel components have the potential to improve clinical outcomes in various medical scenarios. However, AM introduces stability and repeatability concerns, which are potential roadblocks for its widespread use in the medical sector. Micro-CT imaging for non-destructive testing (NDT) is an effective solution for post-manufacturing quality control of these components. Unfortunately, current micro-CT NDT scanners require expensive infrastructure and hardware, which translates into prohibitively expensive routine NDT. Furthermore, the limited dynamic-range of these scanners can cause severe image artifacts that may compromise the diagnostic value of …

The Role Of Transient Vibration Of The Skull On Concussion, Rodrigo Dalvit Carvalho Da Silva

Electronic Thesis and Dissertation Repository

Concussion is a traumatic brain injury usually caused by a direct or indirect blow to the head that affects brain function. The maximum mechanical impedance of the brain tissue occurs at 450±50 Hz and may be affected by the skull resonant frequencies. After an impact to the head, vibration resonance of the skull damages the underlying cortex. The skull deforms and vibrates, like a bell for 3 to 5 milliseconds, bruising the cortex. Furthermore, the deceleration forces the frontal and temporal cortex against the skull, eliminating a layer of cerebrospinal fluid. When the skull vibrates, the force spreads directly to …

Biomechanical Analysis Of Ligament Modelling Techniques And Femoral Component Malrotation Following Tka, Liam A. Montgomery

Electronic Thesis and Dissertation Repository

Previous studies have demonstrated that satisfaction and revision rates following total knee arthroplasty (TKA) are lower than those of comparable surgeries such as total hip replacements. A leading cause for these revisions is joint instability which may be due to improper ligament balancing or poorly aligned surgical implants. One of the methods used to investigate biomechanical forces and kinematics is computational modelling of the post-operative TKA knee.

A unique knee model was used to investigate the biomechanical and kinematic effects of ligament model complexity, as well as the effects of simulating ligament wrapping versus ignoring ligament wrapping. We then used …

Seizure Detection Using Deep Learning, Information Theoretic Measures And Factor Graphs, Bahareh Salafian

Electronic Thesis and Dissertation Repository

Epilepsy is a common neurological disorder that disrupts normal electrical activity in the brain causing severe impact on patients’ daily lives. Accurate seizure detection based on long-term time-series electroencephalogram (EEG) signals has gained vital importance for epileptic seizure diagnosis. However, visual analysis of these recordings is a time-consuming task for neurologists. Therefore, the purpose of this thesis is to propose an automatic hybrid model-based /data-driven algorithm that exploits inter-channel and temporal correlations. Hence, we use mutual information (MI) estimator to compute correlation between EEG channels as spatial features and employ a carefully designed 1D convolutional neural network (CNN) to extract …

The Use Of Ct To Assess Shoulder Kinematics And Measure Glenohumeral Arthrokinematics, Baraa Daher

Electronic Thesis and Dissertation Repository

Recently, studies have started employing dynamic four-dimensional computed tomography (4DCT) imaging as a biomechanical assessment tool. These studies would benefit from the valuable work that has been done in the past using three-dimensional computed tomography (3DCT). Thus, a structured review was conducted to examine the extent and range of methods employing CT imaging to measure shoulder kinematics. The findings of the review were utilized to conduct a study that employed 4DCT imaging to measure glenohumeral joint congruency and arthrokinematics during internal rotation to the back in a population of healthy individuals. The results of this work show the importance of …

Organic-Inorganic Hybrid Biomaterials For Bone Tissue Engineering And Drug Delivery, Neda Aslankoohi

Electronic Thesis and Dissertation Repository

Bone biomaterials prepared from a combination of biodegradable polymers and bioactive glasses offer several advantages, including favorable cell interactions, selective gene expression, and delivery of biomolecules. Furthermore, the interaction of the organic and inorganic phases at the molecular level results in a single-phase hybrid material possessing synergistic properties.

This research aimed to design bone biomaterials from α-amino acid-based poly(ester amide) (PEA) and tertiary bioactive glasses using a sol-gel process. Since incorporating calcium into the bioactive glass network is challenging at sol-gel reaction temperatures, calcium ethoxide and calcium chloride were studied as precursors, and the optimum reaction conditions were identified. Mesoporous …

Characterization Of Tissue-Specific Matrix-Derived Bioscaffolds For Nucleus Pulposus Cell Culture, Marco A. Herrera Quijano

Electronic Thesis and Dissertation Repository

Bioscaffolds derived from the extracellular matrix (ECM) have shown the capacity to promote regeneration by providing tissue-specific biological instructive cues that can enhance cell survival and direct lineage-specific differentiation. This study focused on the development and characterization of two-dimensional (2-D) and three-dimensional (3-D) cell culture platforms incorporating decellularized nucleus pulposus (DNP). First, a novel detergent-free protocol was developed for decellularizing bovine NP tissues that was effective at removing cellular content while preserving key ECM constituents including collagens and glycosaminoglycans. Culture studies showed that 2-D coatings derived from the DNP could support cell attachment but did not maintain or rescue the …

Mixed-Reality Visualization Environments To Facilitate Ultrasound-Guided Vascular Access, Leah Groves

Electronic Thesis and Dissertation Repository

Ultrasound-guided needle insertions at the site of the internal jugular vein (IJV) are routinely performed to access the central venous system. Ultrasound-guided insertions maintain high rates of carotid artery puncture, as clinicians rely on 2D information to perform a 3D procedure. The limitations of 2D ultrasound-guidance motivated the research question: “Do 3D ultrasound-based environments improve IJV needle insertion accuracy”. We addressed this by developing advanced surgical navigation systems based on tracked surgical tools and ultrasound with various visualizations. The point-to-line ultrasound calibration enables the use of tracked ultrasound. We automated the fiducial localization required for this calibration method such that …

4dct Analysis Of In-Vivo Carpal Kinematics During Fem, Manisha R. Mistry

Electronic Thesis and Dissertation Repository

A consensus, detailed understanding of carpal kinematics remains elusive. 4-dimensional CT (4DCT) is a validated modality capable of accurately studying in-vivokinematic motion. The objective of this work is to quantify normal, in-vivo kinematic motion of the carpus through a flexion-extension arc of motion using 4DCT. Ten healthy, un-injured volunteers underwent a 4DCT scanning protocol through a complete arc of flexion-extension motion. Kinematic changes in motion were quantified using helical axis motion data for each carpal bone. Helical axes were compared between bones and statistical analysis performed using repeated-measures ANOVA to identify difference in kinematic motion between bones (p<0.05). The carpus can be divided into four main kinematic blocks: the distal carpal block, the proximal carpal block and individual scaphoid and trapezial blocks. This work supports an additional segmentation of the trapezium from the distal carpal row, which suggests some modulation between the scaphoid and distal carpal row.

Biomaterial For Cervical Intervertebral Disc Prosthesis, Helium Mak

Electronic Thesis and Dissertation Repository

Recent long-term follow-up studies have shown that the cervical disc arthroplasty treatment have potentials in developing surrounding heterotopic ossification (HO). While its cause requires further investigation, this thesis has hypothesized that it may be the result of the continual remodeling of the injured vertebrae caused by the prostheses with smaller footprints introducing abnormal stresses. The research objective of this thesis is to develop a new prosthesis material that can be molded into any form conforming to the size and shape of the end-plates of the affected patient vertebrae. For prototype development, a composite material consisting of 10wt% polyvinyl alcohol cryogel …

Frequency Dependent Diffusion Kurtosis Measurement In The Human Brain With Oscillating Gradients, Kevin B. Borsos

Electronic Thesis and Dissertation Repository

Oscillating gradient spin-echo (OGSE) is an implementation of diffusion MRI that enables shorter effective diffusion times than the conventional pulse gradient spin-echo (PGSE) by periodically modulating the diffusion gradient. Measurements of the diffusion kurtosis, which reflects the degree of restricted diffusion, have previously been prohibited with OGSE due to technical limitations of clinical gradient systems. This thesis presents a novel oscillating gradient waveform that enables the measurement of kurtosis using OGSE without requiring advanced gradient hardware. Decreases of kurtosis are observed in OGSE acquisitions of healthy human subjects relative to PGSE, demonstrating the dependence of the kurtosis on oscillation frequency. …

Diffusion Kurtosis Imaging In Temporal Lobe Epilepsy, Loxlan W. Kasa

Electronic Thesis and Dissertation Repository

Epilepsy constitutes one of the most common neurological clinicopathological entities affecting approximately 1% of the general population. Temporal lobe epilepsy (TLE) represents by far the most common form of medically intractable focal epilepsy in adults. Surgical resection is the common form of treatment when lesions are clearly delineated, either from patient’s magnetic resonance imaging (MRI) structural scans or by invasive seizure monitoring techniques (e.g., intracranial EEG) for patients with non-lesional MRI scans. Increasing numbers of studies have suggested that TLE is more of a network disorder, therefore full delineation of pathological tissue is difficult resulting in incomplete resection, possibly contributing …

Development Of A Wireless Telemetry Load And Displacement Sensor For Orthopaedic Applications, William Anderson

Electronic Thesis and Dissertation Repository

Due to sensor size and supporting circuitry, in vivo load and deformation measurements are currently restricted to applications within larger orthopaedic implants. The objective of this thesis is to repurpose a commercially available low-power, miniature, wireless, telemetric, tire-pressure sensor (FXTH87) to measure load and deformation for future use in biomechanical applications. The capacitive transducer membrane of the FXTH87 was modified, and a relationship was reported between applied compressive deformation and sensor signal value. The sensor package was embedded within a deformable enclosure to illustrate potential applications of the sensor for monitoring load. Finite element analysis was an effective tool to …

Development Of Multifunctional Drug Delivery Systems For Locoregional Therapy, Xinyi Li

Electronic Thesis and Dissertation Repository

Locoregional treatment is the specific delivery of therapeutics to their desired sites of action with minimized systemic adverse effects. In this approach, drug is administered through topical instillation, inhalation, intra-lesional or intra-arterial injection. Decades of experience in locoregional treatment have delivered meaningful benefits to patients with localized diseases (e.g., osteoarthritis, ocular disorders and liver cancers). However, improvements are required for this type of treatment to be more effective. For transarterial chemoembolization (TACE) therapy of hepatocellular carcinoma (HCC), the most current approaches do not allow repeat treatment as the drug delivery vehicle is not degradable. In addition, image contrast agents for …

Snapshot Three-Dimensional Surface Imaging With Multispectral Fringe Projection Profilometry, Parsa Omidi

Electronic Thesis and Dissertation Repository

Fringe Projection Profilometry (FPP) is a popular method for non-contact optical surface measurements, including motion tracking. The technique derives 3D surface maps from phase maps estimated from the distortions of fringe patterns projected onto the surface of an object. Estimation of phase maps is commonly performed with spatial phase retrieval algorithms that use a series of complex data processing stages. Researchers must have advanced data analysis skills to process FPP data due to a lack of availability of simple research-oriented software tools. Chapter 2 describes a comprehensive FPP software tool called PhaseWare^TM that allows novice to experienced users to …

3d Printed Polypyrrole Scaffolds For Ph Dependent Drug Delivery With Applications In Bone Regeneration, Matthew T. Lawrence

Electronic Thesis and Dissertation Repository

Areas of large bone loss are typically healed using autologous bone grafts, seen as the gold standard of care. These materials have a complication rate of 10–40% during harvesting and are limited by the quantity available; therefore the use of 3D printed polymer scaffolds as bone graft alternatives are proposed. Polypyrrole (PPy) is a biocompatible electroactive polymer that has metal-like electrical properties that can be harnessed to hold and release charged drug molecules, triggered by a change in pH. pH fluctuations are seen inside the human body in areas of bone regrowth, which would act as the triggering mechanism for …

Development Of A Wearable Haptic Feedback Device For Upper Limb Prosthetics Through Sensory Substitution, Marco B.S. Gallone

Electronic Thesis and Dissertation Repository

Haptics can enable a direct communication pipeline between the artificial limb and the brain; adding haptic sensory feedback for prosthesis wearers is believed to improve operation without drawing too much of the user's attention. Through neuroplasticity, the brain can become more cognizant of the information delivered through the skin and may eventually interpret it as inherently as other natural senses. In this thesis, a wearable haptic feedback device (WHFD) is developed to communicate prosthesis sensory information. A 14-week, 6-stage, between subjects study was created to investigate the learning trajectory as participants were stimulated with haptic patterns conveying joint proprioception. 37 …

4dct To Examine Carpal Motion, Sydney M. Robinson

Electronic Thesis and Dissertation Repository

Four-dimensional computed tomography (4DCT) is a novel imaging modality initially used in cardiac imaging but recently applied to the musculoskeletal system; although its methodology has been developed, it is still in its infancy as a powerful clinical tool. Currently, scapholunate interosseous ligament (SLIL) tears, whose early symptoms are elucidated through dynamic movement, are diagnosed with static techniques that cannot visualize dynamic motion; hence, a tool is needed that is responsive and dynamic to visualize subtle abnormal carpal movements indicative of SLIL tears. It is hypothesized that 4DCT can visualize subtle dynamic carpal movements to define uninjured motion as well as …

In-Clinic Functional Measurement And Analysis Of Knee Osteoarthritis Patients Undergoing Total Knee Replacement, Riley A. Bloomfield

Electronic Thesis and Dissertation Repository

Prevalence of osteoarthritis is increasing as individuals are remaining active later in life. Since the knee is one of the most commonly affected joints and is involved in almost all daily activities, functional impairment has a substantial impact on overall health. Despite this increase, there currently exists no disease modifying drugs or treatments. Mild cases are managed with physiotherapeutic exercises and common anti-inflammatories but surgical intervention is required for more severe disease progression.

Total knee replacement as a treatment for osteoarthritis is a highly successful surgery that is effective at restoring knee function and reducing pain but still requires further …

Catechol-Containing Copolymers As An Active Ingredient For Denture Adhesives, Vincent Ying Wun Kong

Electronic Thesis and Dissertation Repository

Moisture inside the mouth adds challenge to making denture adhesives formulations. Some formulations have zinc to enhance adhesion on wet skin despite knowing the health hazards. Inspired by mussel foot proteins’ catechol unit’s strong underwater adhesion, nine catechol-containing copolymers (P1A-P3C) were synthesized by free radical polymerization of 3,4-dimethoxystyrene (3,4- DMS) with different styrene derivatives followed by deprotection. P1A-P3C were used to make Fn(P)-C-PBS denture adhesive formulations which had suitable shear stresses around ≥ 5 kPa satisfying ISO 10873. In-situ NMR studies of free radical polymerization of 3,4 - DMS and styrene derivatives allowed computation of their reactivity ratios showing all …

Extracellular Matrix-Derived Microcarriers As 3-D Cell Culture Platforms, Anna Kornmuller

Electronic Thesis and Dissertation Repository

Recognizing the cell-instructive capacity of tissue-specific extracellular matrix (ECM) to direct cell attachment, proliferation and differentiation, there is a need for the development of in vitro cell culture models that reflect the complexity of the ECM to improve stem/progenitor cell expansion and lineage-commitment. This thesis focused on the development and characterization of ECM-derived microcarriers for the in vitro dynamic culture and expansion of stromal cells for cell therapy and tissue engineering applications.

To develop novel platforms for use in dynamic culture systems, initial work focused on applying electrospraying techniques to fabricate microcarriers from decellularized dermal tissue (DDT) and decellularized myocardial …

Fibrin-Based Engineered Vascular Tissues As Platforms For Cellular Studies And Disease Modeling, Khalil Dayekh

Electronic Thesis and Dissertation Repository

Vascular tissue engineering (VTE) is an emerging alternative therapeutic intervention strategy to treat diseases such as atherosclerosis. While the ultimate goal of VTE is designing tissues to serve as graft substitutes, they can also serve as powerful tools to study tissue and disease development and drug discovery.

In this work, engineered vascular tissues from fibrin gel, mouse embryonic multipotent progenitor cell line (10T1/2 cells), and rat embryonic thoracic artery smooth muscle cells (A-10 cells) were used as models to study the Notch signaling pathway and vascular calcification. The 10T1/2 cells were successfully differentiated into vascular smooth muscle cells with TGFβ1 …

Nnemo (Neonatal Neuromonitor) - A Hybrid Optical System To Characterize Perfusion And Metabolism In The Newborn Brain, Ajay Rajaram

Electronic Thesis and Dissertation Repository

Premature birth, defined as a gestational period less than 37 weeks, occurs in 8% of infants born in Canada. These births are associated with a higher risk of developing neurological complications. Infants born with very low birth weights (VLBW, < 1500 g) experience cognitive or behavioural deficits at a rate of 40-50%, while a further 5-10% develop major disorders such as cerebral palsy. The likelihood of injury increases with a shorter gestational period and/or a lower birthweight. Intraventricular hemorrhaging (IVH) occurs in 20-25% of VLBW infants, characterized by bleeding in the germinal matrix and surrounding white matter. This highly vascularized region is particularly susceptible to bleeds due to underdeveloped cerebrovascular structures. Severe IVH causes an inflammatory response and subsequent obstruction of cerebrospinal fluid (CSF) drainage, resulting in enlargement of the brain’s ventricles, referred to as post-hemorrhagic ventricular dilatation (PHVD). PHVD increases intracranial pressure and can result in compression/damage of brain tissue.

Diagnosis of IVH and PHVD is regularly performed using cranial ultrasound. Clinicians can visually assess and grade hemorrhaging/ventricle dilatation. Ultrasound, however, is limited in its ability to continuously monitor and only detects irreversible damage. NNeMo (Neonatal NeuroMonitor) is a hybrid optical device combining diffuse correlation (DCS) and near-infrared spectroscopy (NIRS) to simultaneous monitor cerebral blood flow (CBF) and metabolism at the …

Laparoscopic Image Recovery And Stereo Matching, Wenyao Xia

Electronic Thesis and Dissertation Repository

Laparoscopic imaging can play a significant role in the minimally invasive surgical procedure. However, laparoscopic images often suffer from insufficient and irregular light sources, specular highlight surfaces, and a lack of depth information. These problems can negatively influence the surgeons during surgery, and lead to erroneous visual tracking and potential surgical risks. Thus, developing effective image-processing algorithms for laparoscopic vision recovery and stereo matching is of significant importance. Most related algorithms are effective on nature images, but less effective on laparoscopic images.

The first purpose of this thesis is to restore low-light laparoscopic vision, where an effective image enhancement method …

Motion Intention Estimation Using Semg-Acc Sensor Fusion, Jose Alejandro Lopez

Electronic Thesis and Dissertation Repository

Musculoskeletal injuries can severely impact the ability to produce and control body motion. In order to regain function, rehabilitation is often required. Wearable smart devices are currently under development to provide therapy and assistance for people with impaired arm function. Electromyography (EMG) signals are used as an input to pattern recognition systems to determine intended movements.

However, there is a gap between the accuracy of pattern recognition systems in constrained laboratory settings, and usability when used for detecting dynamic unconstrained movements. Motion factors such as limb position, interaction force, and velocity, are known to have a negative impact on the …