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Medical Biophysics Commons

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Cost-Effective Non-Destructive Testing Of Biomedical Components Fabricated Using Additive Manufacturing, Santiago Fabian Cobos 2022 The University of Western Ontario

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 ...


Seizure Prediction In Epilepsy Patients, Gary Dean Cravens 2022 Nova Southeastern University

Seizure Prediction In Epilepsy Patients, Gary Dean Cravens

NSU REACH and IPE Day

Purpose/Objective: Characterize rigorously the preictal period in epilepsy patients to improve the development of seizure prediction techniques. Background/Rationale: 30% of epilepsy patients are not well-controlled on medications and would benefit immensely from reliable seizure prediction. Methods/Methodology: Computational model consisting of in-silico Hodgkin-Huxley neurons arranged in a small-world topology using the Watts-Strogatz algorithm is used to generate synthetic electrocorticographic (ECoG) signals. ECoG data from 18 epilepsy patients is used to validate the model. Unsupervised machine learning is used with both patient and synthetic data to identify potential electrophysiologic biomarkers of the preictal period. Results/Findings: The model has ...


A Retrospective Dosimetry Comparison To Define Uncertainties Found In A Novel Intensity Modulated Electron Therapy (Imet) Treatment Technique For Use In Radiation Therapy, Marco A. Masciantonio 2022 University of Central Florida

A Retrospective Dosimetry Comparison To Define Uncertainties Found In A Novel Intensity Modulated Electron Therapy (Imet) Treatment Technique For Use In Radiation Therapy, Marco A. Masciantonio

Honors Undergraduate Theses

This study will investigate the difference in radiation at different volumes between traditional electron beam therapy and a novel IMET. The difference in dose will be recorded between the novel IMET and the IMET with a slight shift in the target area. The percent difference between this new model treatment and the model treatment with a shift will be calculated. The main goal of this project is to determine if the target area is still sufficiently treated with this slight shift of the patient in different directions. The percent difference is crucial for the success of this project. It will ...


Deep Convolutional Neural Networks For Accurate Diagnosis Of Covid-19 Patients Using Chest X-Ray Image Databases From Italy, Canada, And The Usa, Amgad A. Salama, Samy H. Darwish, Samir M. Abdel-Mageed, Radwa A. Meshref, Ehab I. Mohamed 2021 Research and Development Center, Air Defense College

Deep Convolutional Neural Networks For Accurate Diagnosis Of Covid-19 Patients Using Chest X-Ray Image Databases From Italy, Canada, And The Usa, Amgad A. Salama, Samy H. Darwish, Samir M. Abdel-Mageed, Radwa A. Meshref, Ehab I. Mohamed

The University of Louisville Journal of Respiratory Infections

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), famously known as COVID-19, has quickly become a global pandemic. Chest X-ray (CXR) imaging has proven reliable, fast, and cost-effective for identifying COVID-19 infections, which proceeds to display atypical unilateral patchy infiltration in the lungs like typical pneumonia. We employed the deep convolutional neural network (DCNN) ResNet-34 to detect and classify CXR images from patients with COVID-19 and Viral Pneumonia and Normal Controls.

Methods: We created a single database containing 781 source CXR images from four different international sub-databases: the Società Italiana di Radiologia Medica e Interventistica (SIRM), the GitHub Database, the ...


Repetitive Mild Traumatic Brain Injury In Mice Triggers A Slowly Developing Cascade Of Long-Term And Persistent Behavioral Deficits And Pathological Changes, Xiaoyun Xu, Matthew Cowan, Flavio Beraldo, Amy Schranz, Patrick McCunn, Nicole Geremia, Zalman Brown, Maitray Patel, Karen L. Nygard, Reza Khazaee, Lihong Lu, Xingyu Liu, Michael J. Strong, Gregory A. Dekaban, Ravi Menon, Robert Bartha, Mark Daley, Haojie Mao, Vania Prado, Marco A.M. Prado, Lisa Saksida, Tim Bussey, Arthur Brown 2021 Robarts Research Institute

Repetitive Mild Traumatic Brain Injury In Mice Triggers A Slowly Developing Cascade Of Long-Term And Persistent Behavioral Deficits And Pathological Changes, Xiaoyun Xu, Matthew Cowan, Flavio Beraldo, Amy Schranz, Patrick Mccunn, Nicole Geremia, Zalman Brown, Maitray Patel, Karen L. Nygard, Reza Khazaee, Lihong Lu, Xingyu Liu, Michael J. Strong, Gregory A. Dekaban, Ravi Menon, Robert Bartha, Mark Daley, Haojie Mao, Vania Prado, Marco A.M. Prado, Lisa Saksida, Tim Bussey, Arthur Brown

Medical Biophysics Publications

We have previously reported long-term changes in the brains of non-concussed varsity rugby players using magnetic resonance spectroscopy (MRS), diffusion tensor imaging (DTI) and functional magnetic imaging (fMRI). Others have reported cognitive deficits in contact sport athletes that have not met the diagnostic criteria for concussion. These results suggest that repetitive mild traumatic brain injuries (rmTBIs) that are not severe enough to meet the diagnostic threshold for concussion, produce long-term consequences. We sought to characterize the neuroimaging, cognitive, pathological and metabolomic changes in a mouse model of rmTBI. Using a closed-skull model of mTBI that when scaled to human leads ...


Investigating Bone Cement Susceptibility Related Artifacts And Adhesion, Eric Kuindersma 2021 The University of Western Ontario

Investigating Bone Cement Susceptibility Related Artifacts And Adhesion, Eric Kuindersma

Electronic Thesis and Dissertation Repository

Blood Oxygen Level Dependent (BOLD) functional Magnetic Resonance Imaging (fMRI) utilizes pulse sequences sensitive to changes in concentration of deoxyhemoglobin to indirectly measure neural activity. Sequences used for BOLD are sensitive to magnetic susceptibility differences that may cause signal voids. Our lab has designed an awake marmoset head coil that eliminates confounds associated with imaging an animal under anesthesia. This design requires a head chamber attached to an animal’s skull with a cement that may cause a susceptibility artifact. Motivation behind this project was to find an MRI compatible cement that remains secure to the skull with minimal artifacts ...


Improved Segmentation Of The Intracranial And Ventricular Volumes In Populations With Cerebrovascular Lesions And Atrophy Using 3d Cnns, Emmanuel E. Ntiri, Melissa F. Holmes, Parisa M. Forooshani, Joel Ramirez, Fuqiang Gao, Miracle Ozzoude, Sabrina Adamo, Christopher J.M. Scott, Dar Dowlatshahi, Jane M. Lawrence-Dewar, Donna Kwan, Anthony E. Lang, Sean Symons, Robert Bartha, Stephen Strother, Jean Claude Tardif, Mario Masellis, Richard H. Swartz, Alan Moody, Sandra E. Black, Maged Goubran 2021 University of Toronto

Improved Segmentation Of The Intracranial And Ventricular Volumes In Populations With Cerebrovascular Lesions And Atrophy Using 3d Cnns, Emmanuel E. Ntiri, Melissa F. Holmes, Parisa M. Forooshani, Joel Ramirez, Fuqiang Gao, Miracle Ozzoude, Sabrina Adamo, Christopher J.M. Scott, Dar Dowlatshahi, Jane M. Lawrence-Dewar, Donna Kwan, Anthony E. Lang, Sean Symons, Robert Bartha, Stephen Strother, Jean Claude Tardif, Mario Masellis, Richard H. Swartz, Alan Moody, Sandra E. Black, Maged Goubran

Medical Biophysics Publications

Successful segmentation of the total intracranial vault (ICV) and ventricles is of critical importance when studying neurodegeneration through neuroimaging. We present iCVMapper and VentMapper, robust algorithms that use a convolutional neural network (CNN) to segment the ICV and ventricles from both single and multi-contrast MRI data. Our models were trained on a large dataset from two multi-site studies (N = 528 subjects for ICV, N = 501 for ventricular segmentation) consisting of older adults with varying degrees of cerebrovascular lesions and atrophy, which pose significant challenges for most segmentation approaches. The models were tested on 238 participants, including subjects with vascular cognitive ...


Development Of A Low Field Mri-Based Approach For Observation Of Water Penetration Into Clay: Preliminary Results, Shivam Gupta 2021 Western University

Development Of A Low Field Mri-Based Approach For Observation Of Water Penetration Into Clay: Preliminary Results, Shivam Gupta

Undergraduate Student Research Internships Conference

Magnetic resonance imaging (MRI) are considered one of the most efficient and non-invasive methods of observing water content in permeable substances. MRI can visualize and quantify the movement of water in real time. In this study, MRI was used to observe the water penetration through clay. Furthermore, MRI can acquire three-dimensional data due to its radio-frequency signals from any orientation. The contrast of the images produced by MRI is a display of the fluid concentration. As such, any change in the contrast intensity is interpreted as a regional change in the concentration of fluid. This report summarizes the preliminary results ...


Simulating 129-Xe Hyperpolarization, Jacob F. Abiad 2021 Western University

Simulating 129-Xe Hyperpolarization, Jacob F. Abiad

Undergraduate Student Research Internships Conference

Hyperpolarized 129-Xe is an important resource in many fields of medical physics and MRI research. The physics of the efficient production of hyperpolarized 129-Xe is therefore equally worth investigation. The main process of hyperpolarizing 129-Xe is Spin Exchange Optical Pumping (SEOP) and is dependent on several physical factors that can be difficult to constantly change in a lab setting. Physical modelling of 129-Xe hyperpolarization allows for the more efficient testing of hyperpolarization physics in a wide array of experimental setups to better determine the optimal values for hyperpolarization. This research project attempted to create a working model for 129-Xe hyperpolarization ...


Effect Of Carbon Monoxide Releasing Molecule 3 (Corm - 3) On Platelet Adhesion To Human Brain Microvascular Endothelial Cells, Najat S. El-Farra 2021 Western University

Effect Of Carbon Monoxide Releasing Molecule 3 (Corm - 3) On Platelet Adhesion To Human Brain Microvascular Endothelial Cells, Najat S. El-Farra

Undergraduate Student Research Internships Conference

Sepsis is characterized by the widespread inflammation of the body. Systemic inflammation activates and recruits inflammatory cells (e.g., leukocytes) and platelets to the affected organs.

During these inflammatory conditions, human brain microvascular endothelial cells (hBMEC) and platelets both upregulate adhesive molecules rendering platelets to adhere to hBMEC.

Although carbon monoxide is thought of as a toxic molecule to many, previous work shows its anti-inflammatory properties. Evidence has shown carbon monoxide-releasing molecules (e.g., CORM-3; that release small, non-toxic amounts of CO) can combat the effects of severe inflammation in several in vivo animal model.

In this current study, we ...


Nnresting State Fmri Scanner Instabilities Revealed By Longitud Inal Phantom Scans In A Multi-Center Study, Aras Kayvanrad, Stephen R. Arnott, Nathan Churchill, Stefanie Hassel, Aditi Chemparathy, Fan Dong, Mojdeh Zamyadi, Tom Gee, Robert Bartha, Sandra E. Black, Jane M. Lawrence-Dewar, Christopher J.M. Scott, Sean Symons, Andrew D. Davis, Geoffrey B. Hall, Jacqueline Harris, Nancy J. Lobaugh, Glenda MacQueen, Cindy Woo, Stephen Strother 2021 University of Toronto

Nnresting State Fmri Scanner Instabilities Revealed By Longitud Inal Phantom Scans In A Multi-Center Study, Aras Kayvanrad, Stephen R. Arnott, Nathan Churchill, Stefanie Hassel, Aditi Chemparathy, Fan Dong, Mojdeh Zamyadi, Tom Gee, Robert Bartha, Sandra E. Black, Jane M. Lawrence-Dewar, Christopher J.M. Scott, Sean Symons, Andrew D. Davis, Geoffrey B. Hall, Jacqueline Harris, Nancy J. Lobaugh, Glenda Macqueen, Cindy Woo, Stephen Strother

Medical Biophysics Publications

Quality assurance (QA) is crucial in longitudinal and/or multi-site studies, which involve the collection of data from a group of subjects over time and/or at different locations. It is important to regularly monitor the performance of the scanners over time and at different locations to detect and control for intrinsic differences (e.g., due to manufacturers) and changes in scanner performance (e.g., due to gradual component aging, software and/or hardware upgrades, etc.). As part of the Ontario Neurodegenerative Disease Research Initiative (ONDRI) and the Canadian Biomarker Integration Network in Depression (CAN-BIND), QA phantom scans were conducted ...


Thermal Properties Of 18f-Fdg Uptake And Imaging In Positron Emission Tomography Scans Of Cancerous Cells, Carleigh R. Eagle 2021 University of North Florida

Thermal Properties Of 18f-Fdg Uptake And Imaging In Positron Emission Tomography Scans Of Cancerous Cells, Carleigh R. Eagle

PANDION: The Osprey Journal of Research and Ideas

Positron Emission Tomography (PET) scans can utilize a radioactive tracer, in this case 2-deoxy2-[fluorine-18] fluoro-D-glucose (18F-FDG), to visualize malignant tumors in cancer patients. The uptake was compared to glucose to understand the difference in thermal properties, which contribute to the ability to image the cancerous cells. The uptake of 18F-FDG by cancer cells and the imaging process of positron emission tomography were reviewed from a thermodynamic perspective. Gastrointestinal and neurological imaging techniques were reviewed to understand the role of PET imaging in different areas of the human body.


Frequency Dependent Diffusion Kurtosis Measurement In The Human Brain With Oscillating Gradients, Kevin B. Borsos 2021 The University of Western Ontario

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 ...


Advancement Of A 3d Computational Phantom And Its Age Scaling Methodologies For Retrospective Dose Reconstruction Studies, Aashish Gupta 2021 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Advancement Of A 3d Computational Phantom And Its Age Scaling Methodologies For Retrospective Dose Reconstruction Studies, Aashish Gupta

The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences Dissertations and Theses (Open Access)

We have used a 3D age-scalable computational phantom for over two decades for retrospective dose reconstruction studies of childhood cancer survivors (CCS) treated with 2D historic radiotherapy (RT). However, our phantom and its age scaling functions (ASF) must be updated so that it can be used in studies that include survivors treated with contemporary RT. We aimed to implement our phantom and its age scaling functions in DICOM format and determine the feasibility of applying our ASFs to accurately scale the whole-body CT-based anatomies.

In the implementation study, we developed Python scripts that model the phantom and ASFs in a ...


Development Of Quantitative Molecular Photoacoustic Imaging For Noninvasive Cancer Diagnostics, Cayla Zandbergen 2021 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Development Of Quantitative Molecular Photoacoustic Imaging For Noninvasive Cancer Diagnostics, Cayla Zandbergen

The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences Dissertations and Theses (Open Access)

Traditional diagnostic imaging provides clinicians with anatomical information that guides both diagnosis and treatment planning; however, once a tumor has progressed enough to be visible, it has often reached an advanced stage. Molecular imaging techniques allow for real-time visualization of chemical and biological processes via imaging of specific biomarkers, which can facilitate detection of malignancies before they become visible. One biomarker of interest is blood oxygen saturation (SO2) due to its correlation with hypoxia, which is associated with increased tumor malignancy; some studies have also established SO2 as an independent biomarker of disease progression. Additionally, because cancerous cells ...


Medical Schools Ignore The Nature Of Consciousness At Great Cost, Anoop Kumar 2021 independent scholar

Medical Schools Ignore The Nature Of Consciousness At Great Cost, Anoop Kumar

Journal of Wellness

The essential question of the relationship between consciousness and matter is ignored in medical school curricula, leading to a machine-like view of the human being that contributes to physician burnout and intellectual dissatisfaction. The evidence suggesting that the brain may not be the seat of consciousness is generally ignored to preserve the worldview of the primacy of matter. By investigating new frameworks detailing the nature of consciousness at different levels of hierarchy, we can bring intellectual rigor to a once opaque subject that supports a fundamental reality about our experience: We are human beings, not only human bodies.


Measuring Inflammation In The Entire Myocardium In A Canine Model Of Myocardial Infarction With Hybrid Pet/Mri, Benjamin Wilk 2021 The University of Western Ontario

Measuring Inflammation In The Entire Myocardium In A Canine Model Of Myocardial Infarction With Hybrid Pet/Mri, Benjamin Wilk

Electronic Thesis and Dissertation Repository

Background: After myocardial infarction (MI), fibrosis and an ongoing dysregulated inflammatory response are associated with adverse cardiac remodeling. Fluorodeoxyglucose (FDG) positron emission tomography (PET) is sensitive to inflammation provided suppression protocols are implemented to restrict the uptake of glucose in myocytes. Magnetic resonance imaging can be used to determine extracellular volume, a surrogate measure of fibrosis. In some cases, patients present with markedly reduced flow in the setting of a large infarct, i.e. microvascular obstruction, restricting the delivery of FDG and contrast agents. To overcome this problem, a constant infusion was explored as an alternative to the clinical standard ...


Three-Dimensional Ultrasound Imaging For Quantifying Knee Cartilage Volume, Samuel Papernick 2021 The University of Western Ontario

Three-Dimensional Ultrasound Imaging For Quantifying Knee Cartilage Volume, Samuel Papernick

Electronic Thesis and Dissertation Repository

Arthritis is the most common chronic health condition in Canada, with the most common form being osteoarthritis (OA). There is a great clinical need for an objective imaging-based point-of-care tool to assess OA status, progression, and response to treatment. This thesis aims to validate a handheld mechanical three-dimensional (3D) ultrasound (US) device against the current clinical standard of magnetic resonance imaging (MRI) for quantifying femoral articular cartilage (FAC) volume. Knee images of 25 healthy volunteers were acquired using 3D US and 3.0 Tesla MRI scans. Two raters manually segmented the trochlear FAC during separate sessions to assess intra- and ...


Current State Of Lgbtqia+ Healthcare, Jessica Vadas 2021 Beaumont Health Resident

Current State Of Lgbtqia+ Healthcare, Jessica Vadas

Conference Presentation Abstracts

No abstract provided.


In Vivo Detection Of Car-T Cell Immunotherapy Using 3 Tesla Fluorine-19 Mri, Veronica Dubois 2021 The University of Western Ontario

In Vivo Detection Of Car-T Cell Immunotherapy Using 3 Tesla Fluorine-19 Mri, Veronica Dubois

Electronic Thesis and Dissertation Repository

Chimeric antigen receptor (CAR) T cell therapy is an emerging cancer treatment that has shown remarkable success in the treatment of B cell malignancies. However, this therapy still has the potential to cause severe toxicities or poor treatment responses in some patients. An imaging tool for tracking CAR-T cells could provide important patient-specific data on CAR-T cell fate. In chapter 2, fluorine-19 magnetic resonance imaging (19F MRI) was evaluated as a method to track the location of 19F perfluorocarbon (PFC) labeled CAR-T cells non-invasively in a mouse model of B cell leukemia. We show for the first time ...


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