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Evaluation Of Perioperative Peripheral Nerve Injury In Cardiac Surgery Using A Novel Automated Ssep Monitoring Device, Satoru Fujii

Electronic Thesis and Dissertation Repository

INTRODUCTION: The high incidence of peripheral nerve injury (PNI) in conventional cardiac surgery (CCS) is believed to result from mechanical injury during sternotomy and/or retraction of the sternum. Minimally invasive cardiac surgery (MICS) is a newly developed type of cardiac surgery which does not require sternotomy or retraction of the sternum. Since surgery related PNI can lead to serious problems for both the patients and care providers, the incidence and details of PNI in cardiac surgery needs to be investigated. OBJECTIVE: To compare the degree of nerve injury in MICS and CCS using somatosensory evoked potential (SSEP) signals. …

A Randomized Controlled Trial Of A Modified Cystoscopy Technique, Khalil Hetou

Electronic Thesis and Dissertation Repository

Introduction

Pain, anxiety and embarrassment are well documented feelings in patients undergoing ambulatory diagnostic cystoscopy. In this study, we explored utilizing Peak-end theory in improving pain perception in patients undergoing diagnostic cystoscopy.

Materials and Methods

We conducted a randomized clinical trial at the London Health Sciences Center for patients undergoing an ambulatory diagnostic cystoscopy for the first time. Males and females as well as allocation ratios were 1:1. The control arm received a standard cystoscopy. In the intervention arm the cystoscope was left for additional 2 minutes without further manipulation in the bladder before scope removal. The primary outcome was …

Measuring The Efficiency Of The Living Kidney Donor Candidate Evaluation Process, Steven Habbous

Electronic Thesis and Dissertation Repository

Background: Living kidney donation is the ideal treatment for many patients with kidney failure. However, the living donor evaluation process has been criticized by patients and healthcare providers as inefficient. In the present research, we evaluated the inefficiency of the living donor evaluation process.

Methods: We conducted a scoping review of the literature and obtained data from large administrative datasets (1256 living donors) and medical chart review (849 prospectively recruited living donors across 12 transplant centres plus retrospective analysis of 1065 living donor candidates from a single centre).

Results: The median time to complete the entire evaluation was 9-11 months …

Acromial Insufficiency Fractures In Reverse Total Shoulder Arthroplasty: A Biomechanical Study, Alicia Kerrigan

Electronic Thesis and Dissertation Repository

Reverse total shoulder arthroplasty (RTSA) is increasingly utilized in the aging population, with a growing list of surgical indications including rotator cuff tear arthropathy, proximal humerus fractures, and revision arthroplasty. Acromial insufficiency fractures following RTSA are poorly understood, difficult to diagnose, and associated with inferior clinical outcomes. There is limited knowledge in the literature regarding the etiology of post-operative acromial fractures. The purpose of this study is to evaluate the role of implant parameters on acromial strain following RTSA.

Using a cadaveric model, a custom designed modular RTSA system was implanted that allowed for evaluation of modifiable parameters including glenoid …

The Role Of Tbx3 In Early Breast Cancer Progression, Milica Krstic

Electronic Thesis and Dissertation Repository

TBX3 is a transcriptional regulator involved in embryonic development and in tumorigenesis of several cancer types. There are two isoforms of TBX3 (TBX3iso1 and TBX3iso2) with different DNA binding domains. The large-scale functional roles of TBX3iso1 and TBX3iso2 were characterized in a breast cancer context. Both TBX3 isoforms induced invasiveness and an epithelial-to-mesenchymal (EMT) phenotype. Coupling data from genome-wide ChIP-array and RNA-Seq studies provided a novel list of genes regulated by each isoform. Both TBX3 isoforms regulate expression of several EMT-related genes, including SLUG and TWIST1. Importantly, TBX3 is a direct regulator of SLUG, and SLUG expression is required for …

Choice Of Implant Filler In Breast Reconstruction: A Study Of The Cost-Effectiveness Of Saline And Silicone Implants, Kathleen Nelligan

Electronic Thesis and Dissertation Repository

Breast reconstruction following mastectomy is increasing and implant-based breast reconstruction is the most common surgical approach. Saline and silicone implants have different cost and complication profiles and it is unclear which is the more cost-effective option. A systematic review of the literature was undertaken to summarize the quality of life data in breast reconstruction, specifically, previously published health state utility values relevant to breast reconstruction. In addition, a cost-utility analysis was undertaken from the perspective of the third-party payer, accounting for the most common complications associated with saline and silicone implants. This demonstrated that despite the increased initial cost of …

Aggregate Morbidity And Mortality Of Defunctioning Loop Ileostomy Fro Formation To Closure: A Large Population Retrospective Cohort Analysis, Mei Yang

Electronic Thesis and Dissertation Repository

There is evidence that defunctioning loop ileostomies (DLIs) are associated with decreased risk of clinically significant anastomotic leaks, but at what cost? This population-based retrospective cohort study used administrative data to investigate differences in outcomes between patients undergoing low anterior resection with and without DLIs. We included all adult patients undergoing low anterior resection from 2002 to 2014 and identified outcomes within 30-days to 2-year of the index surgery. Outcomes included hospital readmission, reoperation, major complications, mortality, bleeding, and ileostomy reversal. DLIs were associated with significantly worse outcomes after low anterior resection, including increased risk of major complication, acute kidney …

Tibiotalar Arthrodesis: Development Of A Novel Jig And Alignment Guide, Adam Mathew Ropchan

Electronic Thesis and Dissertation Repository

Tibiotalar arthrodesis is a surgical procedure, used for the treatment of end-stage ankle arthrosis and instability. There are dozens of described procedures in the literature, all with varying rates of success. Two of the most common reasons for reoperation in tibiotalar arthrodesis are nonunion and infection; few studies have established any associations between patient/surgical factors and reoperation for nonunion and infection.

The first part of this thesis focuses on determining the rate of reoperation to the ipsilateral lower limb and if any patient/surgical factors are associated with reoperation for nonunion and infection. The second part of this thesis turns attention …

Collared Vs. Collarless Total Hip Arthroplasty In Both Direct Anterior And Direct Lateral Approach Surgery: A Prospective Cohort Comparison Study, Seb Heaven

Electronic Thesis and Dissertation Repository

Total hip arthroplasty (THA) is one of the most successful surgical procedures performed worldwide. Recent advances in implant technology and popularization of the muscle-sparing Direct Anterior (DA) approach to the hip has led to younger patients becoming candidates for hip arthroplasty surgery. Among the many considerations necessary for success in this patient population, implant design plays an important role in determining outcomes.

In this thesis, we prospectively evaluated patients who received a collared or collarless fully hydroxyapatite-coated femoral stem during THA with a standard RSA protocol to assess stem migration patterns following surgery.

Preliminary results indicate that collarless stems subside …

Cost Effectiveness Of Bilateral Prophylactic Mastectomy With And Without Different Breast Reconstruction Techniques Versus Screening In Women With High Risk Of Breast Cancer In The Canadian Province Of Ontario, Badria Aljohani

Electronic Thesis and Dissertation Repository

We aimed to investigate the cost-effectiveness of bilateral prophylactic mastectomy (BPM) with and without different reconstruction for the purpose of determining which strategies represent value for money. We developed a decision analytic model to project the lifetime clinical and economic consequences of different strategies. The decision model was parameterized using 10-year follow up and cost data from Ontario administrative health databases and Ontario Cancer registry. Compared to the organized screening-based strategy, surgical strategies ranged from being more effective and cost-saving and up to being associated with an incremental cost effectiveness ratio (ICER) of $63,010 per quality-adjusted life year (QALY) gained, …

Revision Total Knee Arthroplasty Using A Novel 3d Printed Titanium Augment: A Cadaveric Biomechanical Study, Charles-Antoine Dion

Electronic Thesis and Dissertation Repository

During revision total knee arthroplasty (rTKA), proximal tibial bone loss is frequently encountered and can result in a less-stable bone-implant fixation. A 3D printed titanium augment that conforms to the irregular shape of the proximal tibia was recently developed. The purpose of this study was to evaluate the fixation stability of rTKA with this augment in comparison to conventional cemented rTKA.

Fixation stability testing was conducted on eleven pairs of thawed fresh-frozen cadaveric tibias (22 tibias) after primary and revision TKA. During the loading protocol, the bone-implant micromotion was measured using a high-resolution optical system.

There was significantly less micromotion …

White Matter Inflammation And Executive Dysfunction: Implications For Alzheimer Disease And Vascular Cognitive Impairment, Alexander Levit

Electronic Thesis and Dissertation Repository

White matter integrity is crucial to healthy executive function, the cognitive domain that enables functional independence. However, in the ageing brain, white matter is highly vulnerable. White matter inflammation increases with age and Alzheimer disease (AD), which disrupts the normal function of white matter. This may contribute to executive dysfunction, but the relationship between white matter inflammation and executive function has not been directly evaluated in ageing nor AD. White matter is also particularly vulnerable to cerebrovascular disease, corresponding with the common presentation of executive dysfunction in vascular cognitive impairment (VCI). Thus, white matter may be an important substrate by …

Wearable Sensors And Total Knee Arthroplasty: Assessing Quantitative Function To Improve The Patient Experience, Megan Fennema

Electronic Thesis and Dissertation Repository

Osteoarthritis (OA) is a chronic degenerative disease for which the only long-term solution is total knee arthroplasty (TKA), though many patients are not satisfied with their TKA. Satisfaction in TKA patients is not well understood. Subjective questionnaires and objective functional tests have been previously used to assess TKA outcomes, but both have disadvantages. Wearable sensors have facilitated affordable biomechanical measurement in OA and TKA populations. The objective of this work was to use wearable sensors alongside functional tests with TKA patients to identify quantitative function that related to subjective function and satisfaction. A wearable sensor-setup was validated before implementation in …

Effects Of Maternal Protein Restriction On The Pulmonary Surfactant System During The Early Life And Adulthood, Reza Khazaee

Electronic Thesis and Dissertation Repository

Fetal growth restriction (FGR) is defined by low birth weight and contributes to a variety of adult-onset diseases with different severities between males and females. However, the effects of FGR on the pulmonary surfactant are not fully elucidated. In this thesis, first, we investigated the FGR effects on the lung function and the surfactant system at the early postnatal life. It was hypothesized that FGR contributes to alterations of lung mechanics and the surfactant system during the neonatal period. Second, we assessed the FGR effects on the surfactant system in response to sepsis in adulthood. It was hypothesized that FGR …

The Impact Of Free Radical Stabilization Techniques On In Vivo Property Changes In Highly Cross-Linked Polyethylene Acetabular Liners, Michael M. Decker .

Electronic Thesis and Dissertation Repository

Highly cross-linked polyethylene (HXLPE) was introduced into total hip arthroplasty (THA) to reduce long-term wear-related complications. However, HXLPE production and in vivo oxidation can alter mechanical behavior. Mechanical failure of HXLPE liners at the implant rim have been reported. The purpose of this thesis is to determine if thermal free radical stabilization techniques used in HXLPE production alter the mechanical properties, physical properties and oxidative stability of liner rims after extended in vivo time.

Retrieved remelted, single annealed and sequentially annealed HXLPE liner rims were mechanically tested using a validated microindentation technique. Oxidation and crystalline phase composition were measured. Results …

Elucidating Mechanisms Of Innate And Acquired Resistance To Pi3ka Inhibition In Head And Neck Squamous Cell Carcinoma, Kara M. Ruicci

Electronic Thesis and Dissertation Repository

The phosphoinositide 3-kinase (PI3K)/Akt/mechanistic target of rapamycin (mTOR) signalling pathway is aberrantly activated in most head and neck squamous cell carcinomas (HNSCCs). PI3K signalling drives cellular proliferation, protein synthesis and cell survival. Although numerous targeted agents are available to inhibit PI3K signalling, results have been variable and factors influencing response to PI3K inhibition (e.g. genomic aberrations, pathway interconnectivity, acquired drug resistance) are not well defined. In this thesis, we employ a multifaceted approach to elucidate the molecular underpinnings of biomarkers of response and mediators of resistance to PI3K inhibition in HNSCC. We began by combining a large panel of HNSCC …

The Epidemiology Of Infective Endocarditis Among People Who Inject Drugs In London, Ontario., Brian Hallam

Electronic Thesis and Dissertation Repository

Infective endocarditis is an infectious disease that affects the valves of the heart. Injection drug use is currently a leading risk factor among patients with endocarditis. We conducted a prospective study using data from hospital chart records among patients with endocarditis in London, Ontario, which has a relatively high prevalence of people who inject drugs to assess the severity of the issue and the major risk factors of mortality pertaining to this population. This study had a sample size of 353 and included a review of the incidence of admissions of endocarditis, as well as a survival analysis, using both …

The Effects Of Child Restraint System Use And Motor Vehicle Collision Severity On Injury Patterns And Severity In Children 8 Years Old And Younger., Peyton A. Schroeder

Electronic Thesis and Dissertation Repository

Motor vehicle collisions (MVCs) are a leading cause of injury and death for children under the age of 14 years in North America. Children, eight years old or younger, are required to use a child restraint system (CRS) when travelling in a vehicle in Canada. In the present study, the hypothesis that head injury severity of children in this age group, seated in rear rows of vehicles in MVCs, will be influenced by the types of restraint systems used was not supported by the data; however, other secondary aspects of collision data were explored. There were injury patterns that involved …

How Do Health Care Providers Identify And Address Lifestyle Factors With Community Dwelling Adults Who Have Chronic Wounds?, Linda Norton

Electronic Thesis and Dissertation Repository

Wound prevention and management best practice guidelines and literature contain recommendations that treatment plans need to consider the client’s lifestyle but offer little guidance about the specific lifestyle factors to be considered, nor how to address these. A post positivist constructivist grounded theory study was used to explore this gap Participants were health care providers with at least 5 years of experience working with community dwelling adults with chronic wounds. Data were transcripts of two semi structured individual interviews, a reflective journal, relevant documents identified by participants and transcripts of focus groups.

A common understanding of lifestyle factors was not …

Viral Etiology Of Rheumatoid Arthritis, Fatima Kudaeva

Electronic Thesis and Dissertation Repository

Viruses can trigger rheumatoid arthritis (RA) or inflammatory arthritis (IA). Our study provides insight into etiology of RA/IA. We analyzed the evidence relating to the risk of RA after viral infections; estimated the distribution of IA onsets over time; quantified the effect of influenza on the risk of IA.

Results of systematic review and meta-analysis showed that the risk of RA/IA is increased after parvovirus B19 and chikungunya virus. There seems to be a risk of RA after chronic hepatitis C (HCV), but whether it is a true RA or HCV-associated arthritis is not clear.

We estimated the distribution of …

Impact Of Feeding Tube Status On Health Outcomes For Individuals With Oropharyngeal Cancer, Nedeljko Jovanovic

Electronic Thesis and Dissertation Repository

Abstract

This study investigated differences in outcomes related to health, swallowing, and quality of life (QoL) for individuals with oropharyngeal squamous cell carcinoma (OPSCC) receiving either radiotherapy (RT) alone, or concomitant chemoradiotherapy (CRT). Differences were assessed based on whether patients received a feeding tube (FT group) or not (NFT group). Measures including the Functional Oral Intake Scale (FOIS), Performance Status Scale for Head and Neck Cancer (PSS-HN), M.D. Anderson Dysphagia Inventory (MDADI), and weight were collected for 126 individuals at baseline, and at 3, 6, and 12 months post-treatment. Data were analyzed to identify potential prognostic differences between the groups, …

Working Memory And Falls Risk In Older Adults: An Event-Related Potential Study, Yee (Michelle) S. Wong

Electronic Thesis and Dissertation Repository

BACKGROUND: The aging population is rapidly increasing, where currently in North America, the population of older adults (ages 60+) outnumbers the population of children. Falls are a major concern for older adults and their quality of life. Cognitive impairment has been shown to be declined in older adults at-risk for falls, but working memory has not been thoroughly investigated within this population. PURPOSE: To examine differences in Non-Fallers, Moderate Risk for Falls, and Fallers in a working memory task using electroencephalography (EEG). METHODS: Older adults (n=44, female=27) aged 60 – 80 years (m=68.8, SD=4.7) completed two sessions. The first session …

Drug Response And Metabolism In Crohn's Disease, Aze Wilson

Electronic Thesis and Dissertation Repository

Inflammatory bowel disease (IBD) is an illness of chronic intestinal inflammation comprised of Crohn's disease (CD) and ulcerative colitis (UC). Specialists rely heavily on drugs that target a dysregulated immune system. There is a staggering degree of variation in drug response in CD. Our understanding of drug metabolism and response in IBD is limited. Gaining new insights into IBD-specific modifications of drug metabolism may allow for improved drug efficacy and reduced toxicity. Cytochrome P450 (CYP) 3A4 is the most relevant determinant of drug metabolism and exposure for medications prescribed today. CYP3A4 is highly expressed in the liver, but is also …

Non-Cancerous Abnormalities That Could Mimic Prostate Cancer Like Signal In Multi-Parametric Mri Images, Mena Gaed

Electronic Thesis and Dissertation Repository

Prostate Cancer (PCa) is the most common non-cutaneous cancer in North American men. Multi-parametric magnatic resonance imaging (mpMRI) has the potential to be used as a non-invasive procedure to predict locations and prognosis of PCa. This study aims to examine non-cancerous pathology lesions and normal histology that could mimic cancer in mpMRI signals. This study includes 19 radical prostatectomy specimens from the London Health Science Centre (LHSC) that were marked with 10 strand-shaped fiducials per specimen which were used as landmarks in histology processing and ex vivo MRI. Initial registration between fiducials on histology and MR images was performed followed …

Design, Development, Manufacturing And Biomechanical Testing Of Stand-Alone Cage For Posterior Lumbar Interbody Fusion, Fahad Alhelal

Electronic Thesis and Dissertation Repository

Introduction: The most common method of spinal fusion includes pedicle screws instrumentation, either with or without interbody cage fusion. This thesis aimed to develop and test a novel stand-alone intervertebral device that eliminates the need for pedicle screws and rods.

Method: The stand-alone cage was designed in collaboration with spinal surgeons and engineers using computer assisting drawings, and manufactured in titanium by 3D printing. Biomechanical testing comparing the stand-alone cage with standard posterior lumbar interbody fusion (PLIF) in sawbones (n=6) and cadavers (n=8).

Result: Compared to PLIF, the stand-alone cage demonstrated no significant difference in range of flexion, lateral bend …

The Development Of A Temporomandibular Force Simulator To Study Craniofacial Strain In-Vitro, Kenneth Kc Ip

Electronic Thesis and Dissertation Repository

An in-vitro musculoskeletal loading simulator was developed to replicate the internal forces of mastication, and then employed in a comparison of clinically relevant facial fracture repairs. Muscle forces are simulated by pneumatic pistons via 3D printed mounts that are reverse-engineered from CT scan to match muscle attachment sites, which are adhered to bone in order to simulate native stress distributions. Bite force and bone strain pattern of the craniofacial structure under load were measured using a force sensor and strain gauges respectively. In a series of five fresh-frozen cadaveric heads, it was found that strain patterns of the craniofacial structure …

Oncoplastic Surgery: Is It Time To Change? From Innovation To Adoption Using Mentorship Program, Eman Khayat

Electronic Thesis and Dissertation Repository

Oncoplastic surgery is considered the standard of care for breast cancer therapy in numerous Western World countries, particularly in Europe. Despite the advancement of knowledge, Canada still lags in adoption of oncoplasty into the standard surgical practice. In our study, a mentorship program was used to introduce oncoplastic surgery to practicing breast surgeons at LHSC. The change in perception and adoption of oncoplastic surgery were evaluated using semi-structured interviews, before and after the intervention, by qualitative thematic analysis method. Mentorship program was validated as a superior method of learning new surgical techniques by practicing surgeons, demonstrating acceptance of different levels …

Validation Of An Algorithm Allowing Identification Of Primary Spontaneous Pneumothorax Cases From Administrative Databases, Eric Frechette

Electronic Thesis and Dissertation Repository

Introduction: There is no differentiation between primary spontaneous pneumothorax (PSP) and secondary pneumothorax (SP) in the current version of the International Classification of Diseases (ICD-10). Objective: To validate the accuracy of an algorithm that identifies cases of PSP from administrative databases. Methods: The charts of 150 patients who attended the emergency room (ER) with a recorded main diagnosis of pneumothorax were reviewed. The corresponding hospital administrative data collected during previous hospitalizations and ER visits were processed through the proposed algorithm. The results were compared over two different age groups. Results: The results obtained from the PSP algorithm demonstrated a significantly …

Kallikrein-Related Peptidases Are Dysregulated In Pleomorphic Adenoma, Matthew D. Morrison

Electronic Thesis and Dissertation Repository

Objectives: Pleomorphic adenoma (PA) is the most common benign salivary gland tumor. Kallikrein-related peptidases (KLKs) have been identified as biomarkers in many human tumors and may influence tumor behavior. We investigated KLK1-15 messenger ribonucleic acid (mRNA) and proteins in PA specimens to determine a KLK expression profile for this tumor.

Methods: Fresh frozen PA tissue specimens (n = 26) and matched controls were subjected to RT-qPCR to detect KLK1-15 mRNA. Expression of KLK1, KLK12, KLK13 and KLK8 proteins were then evaluated via immunostaining techniques. Statistical analyses were performed with the level of significance set at P < .05.

Results: We observed downregulation …

Acute Pharmacologic Modulation Of Glioblastoma Ph Monitored By Chemical Exchange Saturation Transfer Magnetic Resonance Imaging, Mohammed Albatany

Electronic Thesis and Dissertation Repository

The response of tumor intracellular pH (pH_i) to a pharmacological challenge could help identify aggressive cancer. In addition, tumor pH_i may influence cell proliferation, apoptosis, chemotherapy resistance, and thermosensitivity. Chemical exchange saturation transfer (CEST) is a novel MRI contrast mechanism that is sensitive to cellular pH. More specifically, a CEST method called amine and amide concentration-independent detection (AACID) produces images weighted by intracellular pH (pH_i) and can be used to study pharmacologic pH modulation in tumours.

The overall goal of this thesis was to maximize the magnitude of intracellular tumour acidification using pharmacologic agents. Several …