Radiology Commons^™

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

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 …

Occupational Radiation Exposure Health Risks And Radiation Safety Practices Relative To Interventional Cardiology Providers, Brandon Young

Theses and Graduate Projects

Background: Occupational radiation exposure is a health risk for many healthcare professionals working in interventional cardiology. As technology has progressed, interventional procedures have become more complex and subsequently longer in radiation exposure duration, resulting in a need for radiation safety practices to meet the ever growing demands of the interventional team and ideally outpace these demands.

Methods: A comprehensive systematic literature review was conducted using PubMed. Articles on the health risks of occupational radiation exposure were selected to demonstrate the breadth of potential adverse effects of radiation exposure with less focus on the depth of these effects. Articles covering occupational …

Quantitative Magnetic Resonance Imaging Of Knee Articular Cartilage And Effusion-Synovitis: The Structural Response To Changes In Joint Loading, Hayden F. Atkinson

Electronic Thesis and Dissertation Repository

Knee osteoarthritis (OA) is a progressive degenerative condition that can affect all tissues within the joint. Methods to measure early changes in joint structures and the effect of interventions are required. The purpose of this thesis was to investigate aspects of quantitative magnetic resonance imaging (MRI) as outcome measures in knee OA studies. Specifically, changes in articular cartilage composition and/or effusion-synovitis were examined in people with or at risk for knee OA and healthy controls, and after altering joint loads.

Chapter 2 is a systematic review that studied articular cartilage composition using MRI T2 and T1ρ relaxation in patients at …

Pathophysiology And Proteogenomics Of Post-Infectious And Post-Hemorrhagic Hydrocephalus In Infants, Albert M. Isaacs

Arts & Sciences Electronic Theses and Dissertations

Post-infectious (PIH) and post-hemorrhagic (PHH) hydrocephalus occur as sequalae of neonatal sepsis or intraventricular hemorrhage (IVH) of prematurity, respectively. Together, PIH and PHH represent the most common form of infantile hydrocephalus, the most common indication for neurosurgery in children globally, and the leading cause of neurological morbidity and mortality worldwide. The lack of understanding of the pathophysiology of PIH and PHH, particularly with regards to the host central nervous system response to the antecedent infection and hemorrhage, perturbation of differentiating neural stems in the ventricular (VZ) and subventricular (SVZ) zones, and damage to periventricular white matter (PVWM) tracts carrying sensorimotor …

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, …

Development Of A Ct Metal Artifact Management Algorithm For Proton Therapy Planning (Ampp) For Head And Neck Cancer Patients, Daniela Branco

Dissertations & Theses (Open Access)

Purpose: Dental amalgams (high Z materials) are common sources of artifacts in Head and Neck (HN) images. Commercial artifact reduction techniques have been offered, but many are impractical, produce inaccurate CT images or are not clinically available, thus not widely implemented. The goal of this work is to use CT gantry tilts to develop and evaluate a stereoscopic HN metal artifact management algorithm and investigate its improvement in proton treatment planning.

Methods: The in-house CT metal artifact management method for proton planning (AMPP) uses two angled CT scans to generate a single image set with no metal artifacts posterior …

The Impact Of Temporal Resolution On Clinical Decision-Making For Individuals With Dysphagia, Shauna Corinne Murray

Speech and Hearing Sciences ETDs

INTRODUCTION: Dysphagia, or a disordered swallow, affects up to 1 in 25 individuals in the United States. The gold standard for assessing dysphagia is the videofluoroscopic evaluation of swallowing (VFES). This allows the clinician to observe the swallow anatomy in motion via an X-ray movie, which historically was recorded at 30 frames per second. In recent years VFES have been performed at less frames per second due to radiation concern. This project investigates the effect of using lower temporal resolutions on assessment of video-fluoroscopic swallow studies.

METHODS: In this investigation, 30 swallow studies, all acquired at 30 frames per second, …

A Comparison Between Rectal Dose In Prostate Radiotherapy Patients Treated With Spaceoar Hydrogel Present Versus Patients Treated Without Spaceoar Hydrogel., David Desano

Culminating Experience Projects

Introduction: External beam radiation therapy is a common treatment option for prostate cancer patients with localized disease. Radiation-induced side effects associated with the rectum can impact a patient’s ability to complete treatment or affect the quality of life years after radiation treatment. Spaceoar hydrogel has been developed to reduce radiation dose to nearby pelvis structures, and therefore decreasing potential side effects.

Methods: A total of 20 patients who received definitive radiation therapy to the prostate and seminal vesicles were selected and placed into 2 groups (10 spaceoar, 10 non-spaceoar). The individuals’ age ranged from 60 to 79 years old with …

Dosimetric Effect When Treating Multiple Lesion Srs Using Vmat With And Without Jaw Tracking, Mindy Bui

Culminating Experience Projects

The main purpose of this study was to determine if jaw tracking or non-jaw tracking is the superior technique for patients with multiple brain metastasis that are treated with Volumetric Modulated Radiation Therapy (VMAT) Stereotactic Radiosurgery (SRS). Doses to the organs at risk (OAR) and the target volumes were analyzed using the dose volume histogram (DVH) and dose statistics for each plan. The goal of this study included analyzing the dosimetric effect on the organs at risk and the normal tissue when using jaw tracking versus non jaw tracking. The pros and cons for each technique were identified as well …

Dosimetric Comparison Of Hypofractionated Prostate Radiation With Simultaneous Integrated Boost And Conventional Fractionation With Sequential Boost, Kristina Sammon

Culminating Experience Projects

Introduction: Hypofractionated treatment delivery regimens are associated with better overall long-term disease control for prostate cancer. For patients with high-risk disease, there may be an indication for treatment of the surrounding pelvic lymph nodes for better over-all disease control. In order to achieve a hypofractionated regimen with treatment to the surrounding pelvic lymph nodes a simultaneous integrated boost technique is employed. There are concerns regarding achievability of target dose coverage and limitation of dose to the surrounding organs at risk with this fractionation.

Methods: This study is a retrospective dosimetric analysis of 7 randomly selected patients with high-risk prostate cancer. …

The Air Gap Effect Between A Bolus And The Skin Surface For Chest Wall Irradiation, Marisa Clark

Culminating Experience Projects

Planning technique and bolus choice are important aspects in planning chest wall irradiation (CWI). Many previous studies have tested various combinations of photon energies, electron energies, bolus types and sizes, air gaps sizes, and treatment methods. This study aims to assess the effect of smaller, clinically relevant air gap sizes on specific chest wall treatments using a variety of common bolus types. Due to the Covid-19 pandemic, no data was able to be collected and was instead fabricated by the researcher. Four different treatment plans were created on a phantom patient using various energies of photons (6MV and 10MV) and …

Phantoms To Placentas: Mr Methods For Oxygen Quantification, Kelsey Meinerz

Arts & Sciences Electronic Theses and Dissertations

Molecular oxygen (O2) is vital for efficient energy production and improper oxygenation is a hallmark of disease or metabolic dysfunction. In many pathologies, knowledge of tissue oxygen levels (pO2) could aid in diagnosis and treatment planning. The gold standard for pO2 measures in tissue are implantable probes, which are invasive, require surgery for placement, and are inaccessible to certain regions of the body. Methods for determining pO2 both non-invasively and quantitatively are lacking. The slight paramagnetic nature of O2 provides opportunities to non-invasively characterize pO2 in tissue via magnetic resonance (MR) techniques. As such, O2 can be treated as a …

Development Of Fully Balanced Ssfp And Computer Vision Applications For Mri-Assisted Radiosurgery (Mars), Jeremiah Sanders

Dissertations & Theses (Open Access)

Prostate cancer is the second most common cancer in men and the second-leading cause of cancer death in men. Brachytherapy is a highly effective treatment option for prostate cancer, and is the most cost-effective initial treatment among all other therapeutic options for low to intermediate risk patients of prostate cancer. In low-dose-rate (LDR) brachytherapy, verifying the location of the radioactive seeds within the prostate and in relation to critical normal structures after seed implantation is essential to ensuring positive treatment outcomes.

One current gap in knowledge is how to simultaneously image the prostate, surrounding anatomy, and radioactive seeds within the …

Analysis Of Ptv Margins For Vmat Treatment Of Rectal Cancers Utilizing Prone Bellyboard Device., Ben Armbuster

Culminating Experience Projects

Utilization of a bellyboard device reduces small bowel dose for patients receiving radiation therapy for rectal cancer. The reduction of small bowel dose with the bellyboard is even more significant in intensity modulated radiation therapy rectal treatments, as opposed to conventional 3D treatments. However, there is evidence of increased setup variation with prone bellyboard positioning, especially in pitch and roll. The purpose of this study is to determine the margin needed between the clinical target volume and the planning target volume to adequately account for these setup variations when planning volumetric modulated arc therapy rectal cases utilizing the bellyboard device. …

Prior Mammographic Screening: What Is Its Effect On The Clinical Stage In Newly Diagnosed Breast Cancer Patients At Akuhn., Jillo Bika

Theses & Dissertations

Introduction: Breast cancer is now the leading cancer amongst women in Kenya according to GLOBOCAN 2018. It is also a leading cause of cancer deaths in Kenya, after esophageal and cervical cancer. Mammography is the gold standard in the screening of breast cancer. For screening to be effective, however, it has to be offered to the right patients at the appropriate time and intervals. Up until February of 2019, there were no local guidelines to guide the screening of breast cancer in Kenya. The objective of this study is to assess if prior mammographic screening had an effect on the …

Potential Impacts Of Artificial Intelligence On Spine Imaging Interpretation And Diagnosis, David Howard Durrant

Walden Dissertations and Doctoral Studies

Spine and related disorders represent one of the most common causes of pain and disability in the United States. Imaging represents an important diagnostic procedure in spine care. Imaging studies contain actionable data and insights undetectable through routine visual analysis. Convergent advances in imaging, artificial intelligence (AI), and radiomic methods has revealed the potential of multiscale in vivo interrogation to improve the assessment and monitoring of pathology. AI offers various types of decision support through the analysis of structured and unstructured data. The primary purpose of this qualitative exploratory case study was to identify the potential impacts of AI solutions …

The Labeling Of 99mtc-Psma-Hbed-Cc For Prostate Cancer Imaging, Benchamat Phromphao

Chulalongkorn University Theses and Dissertations (Chula ETD)

Prostate cancer (PCa) is the second most common cancer and the fifth leading cause of death worldwide in 2018 (1). Initially, PCa diagnosis is based on Prostate Specific Antigen (PSA) blood test, which is low sensitivity and low specificity, and sonography guided needle biopsy, which is invasive. Therefore, molecular imaging recently enrolls as an important technique in PCa diagnosis using some small molecules which are well developed to bind to overexpressed Prostate Specific Membrane Antigen (PSMA). The small molecules, for example PSMA-HBED-CC, PSMA I&T, can be chelated with Ga-68 for diagnostic purpose using positron emission tomography (PET) scan. Even though …

The Study Of Local Diagnostic Reference Levels At Unit Of Vascular And Interventional Radiology, King Chulalongkorn Memorial Hospital, Kornkamol Prajamchuea

Chulalongkorn University Theses and Dissertations (Chula ETD)

Interventional Radiology (IR) procedures are minimally invasive surgery using angiographic equipment which the patients and staffs may receive high radiation dose. DRLs, based on 75th percentile of the median dose for a sample of standard sized of patients, are an effective tool for optimization of protection in the medical exposure of patients for diagnostic and interventional procedures (ICRP Publication 135, 2017). The objective of this study is to establish the local DRLs distribution of patient radiation dose and related parameters in interventional radiology procedures in standard-sized of Thai patients. Local DRLs of radiation dose and related parameters of patients (45-75kg …

Evaluation Of Patient Doses From 177lu-Psma In Metastases Prostate Cancer Treatment At King Chulalongkorn Memorial Hospital, Kotchakorn Chatachot

Chulalongkorn University Theses and Dissertations (Chula ETD)

177Lu-PSMA I&T has increasingly used for targeted radionuclide therapy of metastatic castration-resistant prostate cancer (mCRPC). Dosimetric calculation, therefore, is critical to achieve the optimal therapeutic activity while sparing side effects to the normal tissues. The purpose of this study was to determine the radiation dosimetry for metastases prostate cancer patients treated by 177Lu-PSMA I&T at King Chulalongkorn Memorial Hospital (KCMH). Whole-body planar images were acquired in eight patients (12 treatment cycles) at immediately, 4 and 24 h after 177Lu-PSMA I&T injection (range 4.36 to 8.58 GBq). Region of interests (ROIs) were manually contoured on the whole-body, liver, spleen, urinary bladder, …

Development And Dosimetric Verification Of 3d Customized Bolus In Radiotherapy, Nichakan Chatchumnan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Bolus is a tissue equivalent material that is commonly used to reduce the skin-sparing effect in radiotherapy. The commercial flat bolus cannot form perfect contact with the irregular surface of the patient's skin, resulting in an air gap, especially in irregular surface shape. The purpose of this study was to evaluate the feasibility of two types of silicone rubber bolus, RA-00AB, and RA-05AB that were made as to the fabricated flat and 3D customized bolus using 3D printing technology. The 1 cm thick boluses were made from two types of silicone rubber solutions. The point dose and planar dose differences …

Surface And Build-Up Region Dose Measurement In Head And Neck Region Using Radio - Photoluminescent Glass Dosimeter, Sonam Choki

Chulalongkorn University Theses and Dissertations (Chula ETD)

The use of commercially available radio-photoluminescent glass dosimeter (RPLGD) for radiation measurement has increased in recent years. It has been shown to have superior dosimetric characteristics as compared to other dosimeters. The purpose of this research is to evaluate the suitability of the GD-302M glass dosimeter for surface and build-up region dose measurement in head and neck region. The glass dosimeter was analyzed for its dosimetric properties in photon beam. Then, the study was performed for surface and build-up region dose comparison between EBT3 film and RPLGD in solid water phantom at 0, 2, 3, 5, 10 and 15mm depths …

Determination Of Field Output Correction Factors Of Radiophoto Luminescent Glass Dosimeter In 6 Mv Small Photon Beams, Sumalee Yabsantia

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this study was to determine the field output correction factors of radiophotoluminescent glass dosimeter (RPLGD) for 6 MV photon beams by using Monte Carlo (MC) simulation. The ratios of absorbed dose of water and RPLGD were calculated using egs_chamber code for 6 MV, 90-cm SSD, 10-cm depth, and field size range from 0.5 × 0.5 to 10 × 10 cm2. Then the field output correction factors of RPLGD in perpendicular and parallel orientations were determined. Also, the volume averaging correction factors were discovered for supporting our results. Moreover, the comparison of measurement field output factors of RPLGD …

Patient-Specific Organ Dose Calculated By Dose Tracking Software Based On Monte Carlo Simulation In Pediatric Abdominal Ct, Yuparak Innan

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to determine the patient-specific organ doses using Radimetrics dose tracking software in pediatric abdominal CT at Praram9 Hospital. The organ doses were measured using the anthropomorphic Rando phantom inserted with radiophotoluminescent glass dosimeters (RPLGDs) to verify the organ doses calculated by Radimetrics program. The retrospective data were collected from pediatric abdominal CT 164 studies (78 patients), age range 0-15 years-old), who underwent single phase abdominal CT at Praram9 Hospital. The tube voltages ranged between 80 and 135 kVp were adjusted according to the size and age of patients, and rotation time 0.35-0.5 sec. All patients were acquired …

Discordance Between Breast Imaging And Histopathology Findings After Ultrasound Guided Core Needle Biopsy, Margaret Mutinda Mwania

Theses & Dissertations

Introduction: Breast cancer is the most prevalent cancer among women worldwide with an estimated global incidence of 11.6%. According to the GLOBOCAN factsheet, in 2018 breast cancer incidence in Kenya was 40.3 per 100,000. Early detection and diagnosis of breast cancer has been shown to reduce mortality and increase years of life gained. Breast lesion diagnosis is heavily based on imaging and pathology and typically findings are reported independent of one another. Correlation of imaging findings and pathology after biopsy is found to be of critical importance in detecting possible sampling error, concordance versus discordance, recommend appropriate management and thus …