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Full-Text Articles in Radiology

Blunt Cerebrovascular Injury (Bcvi): Universal Cta Neck Screening At Level 2 Trauma Center, Tamine Gogel May 2024

Blunt Cerebrovascular Injury (Bcvi): Universal Cta Neck Screening At Level 2 Trauma Center, Tamine Gogel

Doctor of Nursing Practice Projects

Blunt Cerebrovascular Injury (BCVI) refers to injuries to the vessels supplying blood to the brain, primarily carotid and vertebral arteries, and can result from trauma, resulting in stroke by vessel dissection, thrombus formation, embolization, and hemorrhage. Timely identification is crucial for effective intervention and improved outcomes. This doctoral project proposes the implementation of universal screening using Computed Tomography Angiography (CTA) of the neck during initial workup for blunt force trauma at a Level II ACS-verified trauma center. The primary objective is to mitigate potential delays in diagnosing and treating BCVI, thereby reducing the likelihood of complications. Patients ≥ 15 years …


The Impact Of Simulated Image Acquisition Time Reduction On Image Quality And Parameters Of Myocardial Perfusion Imaging Using A Dedicated Cardiac Camera, Alireza Khatami Jan 2024

The Impact Of Simulated Image Acquisition Time Reduction On Image Quality And Parameters Of Myocardial Perfusion Imaging Using A Dedicated Cardiac Camera, Alireza Khatami

Electronic Thesis and Dissertation Repository

Heart disease is the second leading cause of death in Canada, highlighting the crucial role of early diagnosis in disease management. Myocardial perfusion imaging (MPI), is widely employed for this purpose, involves injecting a radiopharmaceutical into the body, imaging its distribution with a gamma camera, and revealing cardiac blood flow patterns. A significant challenge in MPI is the lengthy 8 to 10 minutes required for stress and rest imaging, potentially causing patient discomfort and compromising image quality due to movement. In a clinical study with 26 patients, post-processed data manipulation simulated a reduction in MPI imaging time. The findings indicated …


Multiparametric Magnetic Resonance Imaging Artificial Intelligence Pipeline For Oropharyngeal Cancer Radiotherapy Treatment Guidance, Kareem Wahid May 2023

Multiparametric Magnetic Resonance Imaging Artificial Intelligence Pipeline For Oropharyngeal Cancer Radiotherapy Treatment Guidance, Kareem Wahid

Dissertations & Theses (Open Access)

Oropharyngeal cancer (OPC) is a widespread disease and one of the few domestic cancers that is rising in incidence. Radiographic images are crucial for assessment of OPC and aid in radiotherapy (RT) treatment. However, RT planning with conventional imaging approaches requires operator-dependent tumor segmentation, which is the primary source of treatment error. Further, OPC expresses differential tumor/node mid-RT response (rapid response) rates, resulting in significant differences between planned and delivered RT dose. Finally, clinical outcomes for OPC patients can also be variable, which warrants the investigation of prognostic models. Multiparametric MRI (mpMRI) techniques that incorporate simultaneous anatomical and functional information …


Sarcopenia In Head And Neck Cancer: A Prognostic Analysis, Nedeljko Jovanovic Mar 2023

Sarcopenia In Head And Neck Cancer: A Prognostic Analysis, Nedeljko Jovanovic

Electronic Thesis and Dissertation Repository

Introduction: In head and neck cancer (HNC), loss of skeletal muscle mass (SMM), or sarcopenia, is a strong prognostic factor for outcomes. However, inconsistencies in its assessment limit our understanding of the relationship between sarcopenia and nutrition-related outcomes. This project evaluated the significance of sarcopenia as described in the literature and as demonstrated in a cohort of HNC patients.

Methods: A scoping review was first conducted followed by a retrospective cohort study with data collected from 194 oropharyngeal carcinoma patients treated with definitive radiation/chemoradiation. Sarcopenia was assessed from computed tomography (CT) imaging at the third cervical vertebra (C3) and the …


Technical Adaptations For Cardiac Sodium Mri, Taylor L. Marcus Oct 2022

Technical Adaptations For Cardiac Sodium Mri, Taylor L. Marcus

Electronic Thesis and Dissertation Repository

Cardiac sodium (Na+) MRI has the potential to unveil relationships between chronic kidney disease (CKD) and cardiovascular disease (CVD). Unfortunately, this modality requires many technical adaptations before it’s possible to extract and compare image data between individuals. This study investigated whether cardiac electrocardiogram (ECG) gating could improve image quality, and whether a uniform phantom could increase signal uniformity if a surface coil is used to acquire the image. Healthy participants were imaged with a custom-built surface coil and 3.0-T MR system. Cardiac gated images presented with a decreased signal-to-noise ratio (SNR), but intensity correction significantly increased image signal …


Lung Cancer Screening: An Evidence-Based Practice Change Project, Robert Bland Dec 2021

Lung Cancer Screening: An Evidence-Based Practice Change Project, Robert Bland

Student Scholarly Projects

Practice Problem: Lung cancer is the leading cause of global cancer deaths and is a significant health issue in the US, claiming more than 155,000 lives each year. Lung cancer screening through low dose computed tomography (LDCT) can reduce lung cancer mortality by 20 percent but unfortunately, lung cancer screening is underutilized.

PICOT Question: The PICOT question that guided this project was: in a patient population eligible for LDCT lung screening (P), how does auditing of practice with feedback to the providers (I), compared to not doing the interventions as mentioned above (C), increase LDCT lung cancer screenings in the …


Imaging Based Prediction Of Pathology In Adult Diffuse Glioma With Applications To Therapy And Prognosis, Evan Gates May 2021

Imaging Based Prediction Of Pathology In Adult Diffuse Glioma With Applications To Therapy And Prognosis, Evan Gates

Dissertations & Theses (Open Access)

The overall aggressiveness of a glioma is measured by histologic and molecular analysis of tissue samples. However, the well-known spatial heterogeneity in gliomas limits the ability for clinicians to use that information to make spatially specific treatment decisions. Magnetic resonance imaging (MRI) visualizes and assesses the tumor. But, the exact degree to which MRI correlates with the actual underlying tissue characteristics is not known.

In this work, we derive quantitative relationships between imaging and underlying pathology. These relations increase the value of MRI by allowing it to be a better surrogate for underlying pathology and they allow evaluation of the …


Investigating Diffusion Tensor Imaging Correlates Of Cognitive Impairment In Idiopathic Normal Pressure Hydrocephalus And Alzheimer's Disease, Omar Hasan, Omar Hasan May 2021

Investigating Diffusion Tensor Imaging Correlates Of Cognitive Impairment In Idiopathic Normal Pressure Hydrocephalus And Alzheimer's Disease, Omar Hasan, Omar Hasan

Dissertations & Theses (Open Access)

Modest expansion of the human brain cerebrospinal fluid (CSF)-filled ventricles is normal with aging, and because of this, it can be difficult for physicians to accurately diagnose and treat enlarged ventricles (ventriculomegaly), called hydrocephalus1 (fluid or water in the brain) Ventriculomegaly occurs due to an obstruction (such as a blood clot or tumor), or a change in CSF absorption2. Primary hydrocephalus, also called idiopathic normal pressure hydrocephalus (iNPH), is non-obstructive and may be comorbid with other neurodegenerative diseases such as Alzheimer’s disease (AD) or frontotemporal dementia (FTD). Clinically, it can be difficult to tell whether the pathophysiological …


The Effects Of Moderate-Severe Plaque Psoriasis On Patient Well-Being And Prevention Of Flares, Glenn Devera Dec 2020

The Effects Of Moderate-Severe Plaque Psoriasis On Patient Well-Being And Prevention Of Flares, Glenn Devera

Nursing | Senior Theses

Psoriasis is a chronic skin condition that is indicated by red, patchy and scaly skin that can be painful when irritated. Patients with psoriasis have an increased risk for a number of chronic diseases. Despite the expansion of treatments for moderate-to-severe psoriasis over the last decade, patients may still find that treatment strategies are not as successful, leaving them dissatisfied with their treatments. A relationship built upon trust between the nurse and the patient diagnosed with psoriasis may serve to help ensure optimal care. A comprehensive literature review was performed and found that best practices for patient management need to …


Hyperpolarized Carbon-13 Magnetic Resonance Measurements Of Tissue Perfusion And Metabolism, Keith Michel Dec 2020

Hyperpolarized Carbon-13 Magnetic Resonance Measurements Of Tissue Perfusion And Metabolism, Keith Michel

Dissertations & Theses (Open Access)

Hyperpolarized Magnetic Resonance Imaging (HP MRI) is an emerging modality that enables non-invasive interrogation of cells and tissues with unprecedented biochemical detail. This technology provides rapid imaging measurements of the activity of a small quantity of molecules with a strongly polarized nuclear magnetic moment. This polarization is created in a polarizer separate from the imaging magnet, and decays continuously towards a non-detectable thermal equilibrium once the imaging agent is removed from the polarizer and administered by intravenous injection. Specialized imaging strategies are therefore needed to extract as much information as possible from the HP signal during its limited lifetime.

In …


Investigating The Metabolic Progression Of Glioblastoma With Hyperpolarized Magnetic Resonance, Travis Salzillo Aug 2020

Investigating The Metabolic Progression Of Glioblastoma With Hyperpolarized Magnetic Resonance, Travis Salzillo

Dissertations & Theses (Open Access)

Rapid diagnosis and therapeutic monitoring of aggressive diseases such as glioblastoma (GBM) can improve patient survival by providing physicians the time to optimally deliver treatment. This includes early in development, while the tumor is still manageable, or following initial therapy, when alternative treatments should be considered. The main goal of this project was to determine whether metabolic imaging with hyperpolarized magnetic resonance spectroscopy (MRS) could detect changes in tumor progression more rapidly than conventional anatomic magnetic resonance imaging (MRI) in patient-derived GBM murine models. To comprehensively capture the dynamic nature of cancer metabolism, in vivo pyruvate-to-lactate conversion with hyperpolarized MRI, …


Parp Pet Imaging Agents, Brandon Carney Feb 2018

Parp Pet Imaging Agents, Brandon Carney

Dissertations, Theses, and Capstone Projects

The poly (adenosine-diphosphate (ADP) ribose) polymerase (PARP) family of enzymes has been of interest to researchers and clinicians for over fifty years, especially the first member of the family, PARP1. This enzyme has become a target for cancer therapeutics due the reliance of highly proliferating cells on PARP1 for genomic maintenance. In the coming age of individualized medicine, however, highly specific therapeutic agents like PARP inhibitors are in need of similarly highly specific companion diagnostic agents. These kind of agents have been made possible with the quickly progressing field of molecular imaging. Specifically, positron emission tomography (PET) has enabled the …


Vena Cava Filter Utilization And Retrieval: A Quality Of Care Issue, Joshua Brown Jan 2016

Vena Cava Filter Utilization And Retrieval: A Quality Of Care Issue, Joshua Brown

Theses and Dissertations--Pharmacy

Vena cava filters (VCFs) are mechanical devices implanted in the inferior vena cava to trap thrombi from travelling to the pulmonary circulation, resulting in pulmonary embolism. VCFs are available as permanent or non-permanent, retrievable devices and are generally indicated for use in patients unable to receive systemic anticoagulation or at exceedingly high risk for pulmonary embolism (PE). Retrievable devices allow for removal of the VCF once the contraindication to anticoagulation or high risk of PE has abated. Since the introduction of retrievable VCFs in the early 2000’s, use of VCFs has increased three-fold, with >85% of all VCFs placed being …


Role Of Cerebrovascular Abnormality In Neurodegenerative Disease And Subcortical Ischemic Disease: Ct Perfusion And Pet Imaging, Jun Yang Sep 2015

Role Of Cerebrovascular Abnormality In Neurodegenerative Disease And Subcortical Ischemic Disease: Ct Perfusion And Pet Imaging, Jun Yang

Electronic Thesis and Dissertation Repository

Clinical studies indicate that about 30% ~ 50% of patients have cognitive impairment after the first or recurrent stroke. Ischemic injury, particularly subcortical lesions, caused by stroke has been demonstrated to further exacerbate cognitive impairment of Alzheimer’s disease (AD) and vascular dementia. However, the mechanisms whereby cerebrovascular abnormalities contribute to neurodegeneration at early stage of disease and eventually to cognitive decline remain unclear. CT perfusion and positron emission tomography (PET) were used to investigate early mechanisms in a rat comorbid model of cerebral ischemia (CI) and β-amyloid (Aβ, a pathological hallmark of AD) toxicity, and in patients with small subcortical …


Magnetic Resonance Imaging Compatible Remote Catheter Navigation System, Mohammad Ali Tavallaei Jul 2015

Magnetic Resonance Imaging Compatible Remote Catheter Navigation System, Mohammad Ali Tavallaei

Electronic Thesis and Dissertation Repository

Many vascular and cardiac diseases are diagnosed and treated using a medical technique known as percutaneous transluminal catheter intervention (PTC). In PTC, the interventionalist inserts a catheter into the vasculature, and using the vessel as the guiding passageway, the catheter is navigated to desired anatomical targets where it would be used for various purposes such as catheter ablation for the treatment/management of cardiac arrhythmias. The catheterization procedure is conventionally guided with x-ray fluoroscopic imaging and more recently, but rarely, with Magnetic Resonance Imaging (MRI). X-ray imaging irradiates the patient directly during the procedure, and the staff and interventionalists indirectly through …


Performance Evaluation Of Material Decomposition Using Rapid Kvp-Switching Dual-Energy Ct For Assessing Bone Mineral Density, John M. Wait May 2014

Performance Evaluation Of Material Decomposition Using Rapid Kvp-Switching Dual-Energy Ct For Assessing Bone Mineral Density, John M. Wait

Dissertations & Theses (Open Access)

Osteoporosis is diagnosed by assessing the bone mineral density (BMD) of the trabecular bone, and has previously been characterized with dual-energy x-ray absorptiometry (DXA) or single-energy computed tomography (SECT). Dual-energy computed tomography (DECT) is able to create two three-dimensional sets of images representing the densities of two materials in a given basis pair. DECT is theoretically capable of providing a true density measurement of trabecular bone material with the proper material basis pair.

Using the rapid kVp-switching GE HD750 scanner, the concentrations of various solutes were assessed in two-material syringe-phantoms in different experimental conditions with DECT material density images, SECT …


Scanned Ion Beam Therapy For Thoracic Tumors, John Gordon Eley Dec 2013

Scanned Ion Beam Therapy For Thoracic Tumors, John Gordon Eley

Dissertations & Theses (Open Access)

Although frequently cured of Hodgkin lymphoma, adolescents and young adults can develop radiation induced second cancers. These patients could potentially benefit from scanned ion radiotherapy yet likely would require motion mitigation strategies. In theory, four-dimensional (4D) optimization of ion beam fields for individual motion states of respiration can enable superior sparing of healthy tissue near moving targets, compared to other motion mitigation strategies. Furthermore, carbon-ion therapy can sometimes provide greater relative biological effectiveness (RBE) for cell sterilization in a target but nearly equivalent RBE in tissue upstream of the target, compared to proton therapy. Thus, we expected that for some …


Physical Activity And Exercise During Adolescence And Young Adulthood Can Act As Preventative Measures Against The Development Of Osteoporosis In Elderly People, Christine C. Center Apr 2013

Physical Activity And Exercise During Adolescence And Young Adulthood Can Act As Preventative Measures Against The Development Of Osteoporosis In Elderly People, Christine C. Center

Honors College Theses

Osteoporosis, “the silent killer,” is responsible for 8.9 million annual fractures. Although not bound to these factors, osteoporosis typically targets females that are post-menopausal and have a family history of the disease. Osteoporosis is caused by a decrease in bone mass density. Physical activity and exercise and often spoken about when the topic of osteoporosis is discussed because of the impact they have on maintaining bone mass density in an effort to delay osteoporosis. This paper first provides an overview of osteoporosis, explanation of methods of diagnosing osteoporosis, risk factors, complications and treatment for osteoporosis. Topics covered include, bone mass …


Repeatability Of Serial Carotid Intima Media Thickness Scanning On Individual Subjects, Judi Nightingale Apr 2007

Repeatability Of Serial Carotid Intima Media Thickness Scanning On Individual Subjects, Judi Nightingale

Loma Linda University Electronic Theses, Dissertations & Projects

Background. Heart disease affects millions of Americans each year. In order to improve primary prevention, early risk identification is essential. B-mode ultrasound of the common carotid artery (CCA) intima-media thickness (IMT) assesses risk of a coronary event early in the process of plaque development. Because IMT changes are so small over time, in order to determine clinically significant versus clinically insignificant changes in IMT over a 12 month time period, a protocol is needed which can detect the least significant difference (LSD) of at least 0.030 mm.

Purpose. The purpose of this study was to develop and test a well-defined …


Development Of Periapical Lesions In Immunosuppressed Rats, Phillip A. Waterman Jr. Aug 1992

Development Of Periapical Lesions In Immunosuppressed Rats, Phillip A. Waterman Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

The pathogenesis of periapical lesions is the interaction of the oral flora with the existing host defenses. The role of bacteria has been established in endodontic disease but the contribution of the host defenses in periapical lesion formation is less clear. The purpose of this study was to compare periapical lesion development in immunosuppressed rats with that in normal rats. Thirty-five, eight-week old Sprague-Dawley rats were equally divided into seven groups. Groups 1, 2, and 3 were given weekly injections of Cytoxan, an immunosuppressive agent. Groups 4, 5, and 6 received no immunosuppressive therapy. Group 7 served as a control, …


Magnetic Resonance Imaging Of Oromandibular Limb Hypogenesis Syndrome (Olhs) : Type 1a Congenital Hypoglossia With Micrognathia, Edmond H. Henken May 1988

Magnetic Resonance Imaging Of Oromandibular Limb Hypogenesis Syndrome (Olhs) : Type 1a Congenital Hypoglossia With Micrognathia, Edmond H. Henken

Loma Linda University Electronic Theses, Dissertations & Projects

An eighteen-year old female with Oromandibular Limb Hypogenesis Syndrome Type 1A was imaged with Magnetic Resonance in the sagittal, coronal, and transverse planes with the jaws closed. The intrinsic muscles of the tongue, genioglossus, geniohyoid, mylohyoid, medial and lateral pterygoid muscles were identified and compared with a control of the same age and sex. All the muscles in question were present. Combined with the intrinsic muscles of the tongue, the genioglossus were approximately one-half the size of the control in the sagittal plane. The geniohyoid of the OLHS subject was enlarged most probably due to the hyperactivity of the floor …