Medicine and Health Sciences Commons^™

The Development And Testing Of A Gyroscope-Based Neck Strengthening Rehabilitation Device, Nicole D. Devos

Electronic Thesis and Dissertation Repository

Neck pain can be debilitating, and is experienced by the majority of people at some point over the course of their life. Resistance training has been shown to have significant improvement in pain or disability for patients. There are few options available for telerehabilitation, and the use of gyroscope stabilizers is proposed for this use. A biomechanics model of a head--neck--gyroscope system was created. In order to also model the dynamics of such a system, this work proposes a blended method using the Denavit--Hartenberg (DH) convention, popular in the field of robotics, with the Lagrangian mechanics approach to analyze an …

Development And Validation Of Mechatronic Systems For Image-Guided Needle Interventions And Point-Of-Care Breast Cancer Screening With Ultrasound (2d And 3d) And Positron Emission Mammography, Claire Ks Park

Electronic Thesis and Dissertation Repository

The successful intervention of breast cancer relies on effective early detection and definitive diagnosis. While conventional screening mammography has substantially reduced breast cancer-related mortalities, substantial challenges persist in women with dense breasts. Additionally, complex interrelated risk factors and healthcare disparities contribute to breast cancer-related inequities, which restrict accessibility, impose cost constraints, and reduce inclusivity to high-quality healthcare. These limitations predominantly stem from the inadequate sensitivity and clinical utility of currently available approaches in increased-risk populations, including those with dense breasts, underserved and vulnerable populations.

This PhD dissertation aims to describe the development and validation of alternative, cost-effective, robust, and high-resolution …

Using Statistics, Computational Modelling And Artificial Intelligence Methods To Study And Strengthen The Link Between Kinematic Impacts And Mtbis, Andrew Luke Mcconnell Patterson

Electronic Thesis and Dissertation Repository

Mild traumatic brain injuries (mTBIs) are frequently occurring, yet poorly understood, injuries in sports (e.g., ice hockey) and other physical recreation activities where head impacts occur. Helmets are essential pieces of equipment used to protect participants’ heads from mTBIs. Evaluating the performance of helmets to prevent mTBIs using simulations on anatomically accurate computational head finite element models is critically important for advancing the development of safer helmets. Advancing the level of detail in, and access to, such models, and their continued validation through state-of-the-art brain imaging methods and traditional head injury assessment procedures, is also essential to improve safety. The …

Computer Vision-Based Hand Tracking And 3d Reconstruction As A Human-Computer Input Modality With Clinical Application, Tania Banerjee

Electronic Thesis and Dissertation Repository

The recent pandemic has impeded patients with hand injuries from connecting in person with their therapists. To address this challenge and improve hand telerehabilitation, we propose two computer vision-based technologies, photogrammetry and augmented reality as alternative and affordable solutions for visualization and remote monitoring of hand trauma without costly equipment. In this thesis, we extend the application of 3D rendering and virtual reality-based user interface to hand therapy. We compare the performance of four popular photogrammetry software in reconstructing a 3D model of a synthetic human hand from videos captured through a smartphone. The visual quality, reconstruction time and geometric …

Improving The Reliability And Accessibility Of Ct Perfusion Imaging In Acute Ischemic Stroke, Kevin J. Chung

Electronic Thesis and Dissertation Repository

CT perfusion (CTP) imaging is a validated treatment decision support tool in acute ischemic stroke. Automated analysis of CTP cerebral blood flow (CBF) and Tmax maps produces estimates of ischemic core and penumbra volumes used to determine target mismatch profiles for treatment. However, availability and utilization of CTP is low due to diagnostic variability between CTP software and technical, logistical, and radiation dose considerations that may limit its routine adoption. The objective of this doctoral research was to improve the reliability and accessibility of CTP by (1) improving diagnostic agreement between CTP software, (2) enabling perfusion imaging with standard acute …

A Framework For Stable Robot-Environment Interaction Based On The Generalized Scattering Transformation, Kanstantsin Pachkouski

Electronic Thesis and Dissertation Repository

This thesis deals with development and experimental evaluation of control algorithms for stabilization of robot-environment interaction based on the conic systems formalism and scattering transformation techniques. A framework for stable robot-environment interaction is presented and evaluated on a real physical system. The proposed algorithm fundamentally generalizes the conventional passivity-based approaches to the coupled stability problem. In particular, it allows for stabilization of not necessarily passive robot-environment interaction. The framework is based on the recently developed non-planar conic systems formalism and generalized scattering-based stabilization methods. A comprehensive theoretical background on the scattering transformation techniques, planar and non-planar conic systems is presented. …

The Design And Evaluation Of A Subacromial Implant In Restoring Normal Glenohumeral Joint Stability In The Presence Of A Massive Irreparable Rotator Cuff Tear, Cole T. Fleet

Electronic Thesis and Dissertation Repository

Massive irreparable rotator cuff tears are a common cause of pain and disability. Several different treatment options are available for this pathology; however, these treatments have been associated with poor clinical outcomes when used to treat younger (<65 years), more active patients. The purpose of this thesis was to design and evaluate a subacromial implant in its ability to restore normal glenohumeral stability and range of motion. The implant was created as a modular device, which captured different implant thicknesses (5mm and 8mm) and constraints (high and low) within its design. In-vitro testing compared the ability of these implants to restore normal shoulder biomechanics. The results indicated the 5mm high constraint implant to be the most effective in restoring normal joint position. Furthermore, range of motion increased when the implant was paired with a tuberoplasty procedure. These results suggest this implant may be advantageous in treating younger patients.

The Development Of A Motion Sensing Device For Use In A Home Setting, Jaspreet K. Kalsi

Electronic Thesis and Dissertation Repository

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease, with over 10 million individuals diagnosed with PD world-wide. The most common symptom characterized by PD is tremor. Tremor is an involuntary oscillatory motion that most prominently occurs in upper limb, specifically in the hand and wrist that has a measurable frequency and amplitude. This thesis aims to evaluate the usability and functionality of a tremor sensing device designed to collect quantitative data on individuals with PD. The designed device uses 23 commercially-available inertial measuring units (IMUs) located between 21 joints: distal interphalangeal (DIP) joints, proximal interphalangeal (PIP) joints, Interphalangeal …

A Two-Layer Continuous-Capillary Oxygen Transport Model: Development And Application To Blood Flow Regulation In Resting Skeletal Muscle., Keith C. Afas

Electronic Thesis and Dissertation Repository

In skeletal muscle (SM), the microcirculation distributes blood flow to capillary networks to meet local oxygen (O₂) demand. Experiments using intra-vital video microscopy (IVVM) have quantified blood flow and O₂ supply in capillary networks, and using an O₂ exchange chamber have measured local changes in blood flow believed due to O₂-dependent regulation. However, IVVM is unable to simultaneously measure capillary O₂ supply and SM O₂ content, implying the need for theoretical models to understand how flow regulation and SM oxygenation interact. In this thesis, a novel blood-tissue O₂ transport model using …

To Develop A Clinically Friendly Multi-Segment Kinematic And Kinetic Foot Model And Test It On Pre-/Post-Hto Patients With Medial Knee Osteoarthritis And Knee Varus, Songlin Zhu

Electronic Thesis and Dissertation Repository

This study aims to develop a clinically useful multi-segment foot model that will enable the analysis of foot kinematics and kinetics in an optical motion capture laboratory setting. This study will also test the new multi-segment foot model on patients with knee osteoarthritis and varus knee alignment that is corrected by high tibial osteotomy (HTO). The multi-segment foot model divides the foot into four functional segments: the hindfoot, midfoot, forefoot and hallux. An X-Z-Y-Cardan angle rotation convention was used to determine intersegmental dorsi/plantar flexion, inversion/eversion, and internal/external rotation. Joint moments, joint powers and medio-longitudinal arch (MLA) height/length ratio were also …

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 …

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 …

Effect Of Levodopa On Eeg Connectivity In Parkinson's Patients, Sepehr Torab Parhiz

Electronic Thesis and Dissertation Repository

Levodopa is a dopamine replacement medication administered to patients with Parkinson’s disease (PD) to alleviate their motor symptoms. However, its long-term use can cause adverse side effects, including involuntary motor movements. We studied 16 PD patients before and after taking Levodopa based on resting-state electroencephalography (EEG) recordings to determine how Levodopa affects the functional connectivity of their brain networks. We used several metrics from graph theory, in particular the minimum spanning tree (MST) metric, and analyzed how they change after subjects take Levodopa. We observed significant changes in the lower alpha band toward a more path-like and less globally efficient …

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.

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. …

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 …

In Vitro Analyses Of The Contributions Of The Hip Capsule To Joint Biomechanics, Emma Donnelly

Electronic Thesis and Dissertation Repository

Optimal management of the hip capsule during arthroscopic surgery has not been established. The impact of incisions made to the capsule during minimally invasive procedures on joint biomechanics, and whether repair provides any benefit, continue to be debated. The effectiveness of capsular repair to restore native kinematics may be insufficient. Therefore, a better understanding of joint behavior during various capsule conditions is needed. A new robotic system was used to analyze the effect of progressive capsulotomy incision and repairs on the behavior of a normal hip within range of motion (ROM) limits with respect to the intact joint. Complete repairs …

An Investigation On The Influences Of Radial Head Hemiarthroplasty Stem Fixation Techniques On Articular Mechanics, Jakub Szmit

Electronic Thesis and Dissertation Repository

Radial head hemiarthroplasty design has been extensively studied with a focus on utilizing the geometrical characteristics of the native radial dish as a guide of implant placement and design. Although implant design has been studied, optimal radial head implant fixation technique remains unknown. This thesis focused on the effect of stem fit on radiocapitellar contact mechanics, using both finite element and experimental bench-top approaches. Additionally, investigation into the impact of varus/valgus malalignment of the radial head in both the native state and following hemiarthroplasty was conducted. It was found that loose fitting a smooth stem axisymmetric radial head implant through …

Development Of Water-Soluble Polyesters For Tissue Engineering Applications, Trent Gordon

Electronic Thesis and Dissertation Repository

The development of tunable polymers has become increasingly important for both tissue engineering and drug delivery. This thesis investigates the development of water-soluble polyesters that contain both natural and synthetic components. These polymers offer tunable chemical structures, as well as functional groups for the conjugation of crosslinking moieties or cell signaling molecules. The first series of polymers was synthesized from poly(ethylene glycol) (PEG) and aspartic acid (Asp) via a titanium catalyzed transesterification method to provide polymers with molar masses of 12 kg/mol. After deprotection, the pendent functional groups of Asp were reacted with methacrylic, maleic, and itaconic anhydride to introduce …

Navigation And Patient Specific Instrumentation In Shoulder Arthroplasty, Joseph Cavanagh

Electronic Thesis and Dissertation Repository

The humeral head osteotomy influences shoulder arthroplasty component height, version and neck shaft angle and therefore outcomes. The purpose of this study is to develop and utilize navigation to execute the osteotomy.

3D printed models were used to develop a navigation technique, and then to execute planned osteotomies. Free hand, fixed angle guide, patient specific guides, and real time navigation osteotomies were completed. The height, neck shaft angle and version were recorded. Also collected, were the planes of the guides once they were placed.

Navigation had significantly less error from the planned osteotomy in neck shaft angle versus all other …

A Biomechanical Investigation Into The Effect Of Experimental Design On Wrist Biomechanics And Contact Mechanics, Clare E. Padmore

Electronic Thesis and Dissertation Repository

The wrist is one of the most commonly injured joints, and injury can have serious sequelae if pathological healing ensues. Strides have been made to understand normal and pathological wrist biomechanics using experimental approaches, which has contributed to improved patient care. The present work advances our understanding of the influence of experimental techniques and joint motion measurement techniques on in-vitro wrist biomechanical cadaveric studies, and applies the knowledge learned to a common clinical entity of scapholunate insufficiency.

First, the relative contributions of the carpal rows to wrist motion were assessed, in addition to the identification of limitations of current biomechanical …

Metal Additive Manufacturing For Fixed Dental Prostheses, Mai El Najjar

Electronic Thesis and Dissertation Repository

The use of additive manufacturing (AM) in dentistry has gained momentum in recent years. However, high initial costs and uncertainty surrounding the quality of AM products are considered barriers to their use. This research compared dental substructures fabricated by AM versus conventional casting and milling.

Cobalt-chromium alloy rectangular bars and three-unit bridge substructures were fabricated by AM, casting or milling. Bars manufactured by AM exhibited superior flexural strength, shear bond strength of porcelain coating, and Vickers hardness. Bridge substructures fabricated by AM showed similar flexural stiffness to cast, similar flexural loads at failure to milled and cast, and overall accuracy …

The Of Application Of 3d-Printing To Lumbar Spine Surgery, Andrew J. Kanawati

Electronic Thesis and Dissertation Repository

Rapid prototyping refers to the manufacturing process in which a three-dimensional (3D) digital model can be transformed into a physical model by layering material in the shape of successive cross sections atop of previously layers. Rapid prototyping has been increasing in popularity in the field of medicine and surgery due to the ability to personalize various aspects of patient care. The thesis will explore the use of rapid prototyping in lumbar spine surgery, aim to quantify the accuracy of medical imaging when relating to imaged structures and their corresponding models produced by rapid prototyping, and determine if complex patient-specific guides …

Structure-Function Relationships In The Brain: Applications In Neurosurgery, Daiana-Roxana Pur

Electronic Thesis and Dissertation Repository

Multimodal brain imaging allows the study of structure-function relationships of the brain at the individual level, a key subject in basic neuroscience with important applications in neurosurgery. The current thesis aims to better understand these relationships by (1) examining how cortical morphology metrics influence measures of brain function, (2) their visualization in augmented reality (AR), and (3) their application in neurosurgical planning. To achieve these objectives, we made use of multimodal magnetic resonance imaging (MRI) data: diffusion weighted imaging, resting-state functional MRI (rs-fMRI), task-based fMRI, and T1-weighted images. Various metrics were calculated: cortical thickness (CT), blood oxygen level dependent signal …

Machine Learning Towards General Medical Image Segmentation, Clara Tam

Electronic Thesis and Dissertation Repository

The quality of patient care associated with diagnostic radiology is proportionate to a physician's workload. Segmentation is a fundamental limiting precursor to diagnostic and therapeutic procedures. Advances in machine learning aims to increase diagnostic efficiency to replace single applications with generalized algorithms. We approached segmentation as a multitask shape regression problem, simultaneously predicting coordinates on an object's contour while jointly capturing global shape information. Shape regression models inherent point correlations to recover ambiguous boundaries not supported by clear edges and region homogeneity. Its capabilities was investigated using multi-output support vector regression (MSVR) on head and neck (HaN) CT images. Subsequently, …

Objective Estimation Of Tracheoesophageal Speech Quality, Yousef S Ettomi Ali

Electronic Thesis and Dissertation Repository

Speech quality estimation for pathological voices is becoming an increasingly important research topic. The assessment of the quality and the degree of severity of a disordered speech is important to the clinical treatment and rehabilitation of patients. In particular, patients who have undergone total laryngectomy (larynx removal) produce Tracheoesophageal (TE) speech. In this thesis, we study the problem of TE speech quality estimation using advanced signal processing approaches. Since it is not possible to have a reference (clean) signal corresponding to a given TE speech (disordered) signal, we investigate in particular the non-intrusive techniques (also called single-ended or blind approaches) …

Investigation Of Visual Perceptions In Parkinson's Disease And The Development Of Disease Monitoring Software, Matthew Bernardinis

Electronic Thesis and Dissertation Repository

Non-motor Parkinson’s Disease (PD) symptoms are substantial factors of PD arising throughout disease stages, yet their diagnosis and monitoring remain a challenge. Sensory abnormalities in PD occur across sensory systems and disease stages, contributing to disease-related impairments. However, the extent of symptoms is unknown, with inadequate monitoring and treatment options furthering disease management difficulties. The current work studies movement-independent visual perceptions of time, displacement and velocity in PD patients across disease stages using levodopa, deep brain stimulation (DBS), or no PD therapy. Perceptual tasks were conducted using a computer-generated graphical device designed with a focus on simplicity and flexibility. Perception …

Parkinsonian Speech And Voice Quality: Assessment And Improvement, Amr Gaballah

Electronic Thesis and Dissertation Repository

Parkinson’s disease (PD) is the second most common neurodegenerative disease. Statistics show that nearly 90% of people impaired with PD develop voice and speech disorders. Speech production impairments in PD subjects typically result in hypophonia and consequently, poor speech signal-to-noise ratio (SNR) in noisy environments and inferior speech intelligibility and quality. Assessment, monitoring, and improvement of the perceived quality and intelligibility of Parkinsonian voice and speech are, therefore, paramount. In the first study of this thesis, the perceived quality of sustained vowels produced by PD patients was assessed through objective predictors. Subjective quality ratings of sustained vowels were collected from …

Quantifying The Outcomes Of A Virtual Reality (Vr)-Based Gamified Neck Rehabilitation, Shahan Salim

Electronic Thesis and Dissertation Repository

Neck pain is a major global public health concern and adds a significant financial burden to both the healthcare system as well as people suffering from it. Additionally, it presents measurement and evaluation challenges for clinicians as well as adherence challenges and treatment barriers for the patients. We have developed a virtual reality (VR)-based video game that can be used to capture outcomes that may aid in the assessment and treatment of neck pain. We investigated: (i) performance metrics of overall accuracy, accuracy based on movement difficulty, duration, and total envelope of movement; (ii) stability across sessions; (iii) accuracy across …

Improving Material Mapping In Glenohumeral Finite Element Models: A Multi-Level Evaluation, Nikolas K. Knowles

Electronic Thesis and Dissertation Repository

An improved understanding of glenohumeral bone mechanics can be elucidated using computational models derived from computed tomography data. Although computational tools, such as finite element analysis, provide a powerful quantitative technique to evaluate and answer a variety of biomechanical and clinical questions, glenohumeral finite element models (FEMs) have not kept pace with improvements in modeling techniques or model validation methods seen in other anatomic locations. The present work describes the use of multi-level computational modeling to compare, develop and validate FEMs of the glenohumeral joint.

Common density-modulus relationships within the literature were evaluated using a multi-level comparative testing methodology to …