Proposed Method For Measuring The Let Of Radiotherapeutic Particle Beams, Stephen D. Bello

Physics & Astronomy ETDs

The Bragg peak geometry of the depth dose distributions for hadrons allows for precise and effective dose delivery to tumors while sparing neighboring healthy tissue. Further, compared against other forms of radiotherapeutic treatments, such as electron beam therapy (EBT) or photons (x and \(\gamma\)-rays), hadrons create denser ionization events along the particle track, which induces irreparable damage to DNA, and thus are more effective at inactivating cancerous cells. The measurement of radiation's ability to inactivate cellular reproduction is the relative biological effectiveness (RBE). A quality related to the RBE that is a measurable physical property is the linear energy transfer …

Development Of Physics Curriculum For Pre-Health Students, Elliot Eckman Mylott

Dissertations and Theses

Many pre-health students are required to take introductory physics as undergraduates, though they often struggle to see the relationship between medicine and what they learn in these courses. In order to help students make that connection, reformed curriculum was adopted that teaches physics through the context of biomedicine. This dissertation will discuss the development, implementation, and assessment of the reformed curriculum for the introductory and intermediate level physics courses that targets the needs of pre-health students.

The curriculum created during this project include laboratory activities, multimedia content, and other instructional materials all of which present physics in biomedical contexts. The …

Improvements In Four-Dimensional And Dual Energy Computed Tomography, Rachael M. Martin

Dissertations & Theses (Open Access)

Dual energy and 4D computed tomography (CT) seek to address some of the limitations in traditional CT imaging. Dual energy CT, among other purposes, allows for the quantification and improved visualization of contrast materials, and 4D CT is often used in radiation therapy applications as it allows for the visualization and quantification of object motion. While much research has been done with these technologies, areas remain for potential improvement, both in preclinical and clinical settings, which will be explored in this dissertation. Preclinical dual energy cone-beam CT (CBCT) can benefit from wider separation between the peak energy of the two …

Volumetric, Magnetic Resonance-Visible, And Radiation-Sensitive Detectors For Magnetic Resonance Image-Guided Radiation Therapy, Hannah J. Lee

Dissertations & Theses (Open Access)

VOLUMETRIC, MAGNETIC RESONANCE-VISIBLE, AND RADIATION-SENSITIVE DETECTORS FOR MAGNETIC RESONANCE IMAGE-GUIDED RADIATION THERAPY

Hannah Jungeun Lee

Advisory Professor: Geoffrey S. Ibbott, Ph.D.

Due to the superior soft-tissue contrast of magnetic resonance imaging (MRI) compared to conventional computed tomography (CT) and other on-board imaging techniques, several groups have integrated MRI and radiation treatment machine systems. The advent of MR image-guided radiation therapy (MR-IGRT) using systems, such as the 1.5 MRI – 7 MV linear accelerator (MR-Linac), now allow for improved soft-tissue on-board imaging for patient position and tumor target localization verification and the ability to assess functional biological tissue characteristics with MRI, …

Basic Vision Research With Clinical Applications And Science Education Assessments, Andrew Wilson

Electronic Theses and Dissertations

Visual Acuity (VA) examinations are one of the most commonly conducted medical assessment throughout the world. Recent advances in computer technology allows for new forms of visual assessment to be conducted. In Part I of this thesis I demonstrate the capability of an automated computer program named VISION to assess human visual acuities. Different color combinations of an object against a background emitted from a computer screen are used to examine a variety of human color vision acuities. Results indicated a large difference in acuity scores between human subjects tested with these different color combinations. A single human subject exhibits …

Detecting And Evaluating Therapy Induced Changes In Radiomics Features Measured From Non-Small Cell Lung Cancer To Predict Patient Outcomes, Xenia J. Fave

Dissertations & Theses (Open Access)

The purpose of this study was to investigate whether radiomics features measured from weekly 4-dimensional computed tomography (4DCT) images of non-small cell lung cancers (NSCLC) change during treatment and if those changes are prognostic for patient outcomes or dependent on treatment modality. Radiomics features are quantitative metrics designed to evaluate tumor heterogeneity from routine medical imaging. Features that are prognostic for patient outcome could be used to monitor tumor response and identify high-risk patients for adaptive treatment. This would be especially valuable for NSCLC due to the high prevalence and mortality of this disease.

A novel process was designed to …

Developments In Pet-Mri For Radiotherapy Planning Applications, John Christian Patrick

Electronic Thesis and Dissertation Repository

The hybridization of magnetic resonance imaging (MRI) and positron emission tomography (PET) provides the benefit of soft-tissue contrast and specific molecular information in a simultaneous acquisition. The applications of PET-MRI in radiotherapy are only starting to be realised. However, quantitative accuracy of PET relies on accurate attenuation correction (AC) of, not only the patient anatomy but also MRI hardware and current methods, which are prone to artefacts caused by dense materials. Quantitative accuracy of PET also relies on full characterization of patient motion during the scan. The simultaneity of PET-MRI makes it especially suited for motion correction. However, quality assurance …

Novel Compound, 84f2, Inhibits Calmodulin Deficient Ryr2, Robert Carl Klipp

Dissertations and Theses

The cardiac ryanodine receptor (RyR2) plays a key role in excitation-contraction coupling (ECC). Mutations in RyR2 are known to be linked to the arrhythmogenic disorder, catecholaminergic polymorphic ventricular tachycardia (CPVT), a deadly disease which is characterized by a leak of calcium from sarcoplasmic reticulum and a decrease in calmodulin (CaM) binding. A novel drug, 84F2, shown to inhibit arrhythmias in RyR2-R176Q heterozygous CPVT mouse hearts (2.5 µg/kg), decrease spark frequency in cells derived from CPVT mice (IC₅₀ = 35 nM), and inhibit RyR2 single channel activity at low nanomolar concentrations (IC₅₀ = 8 nM). When CaM is added …

Design Of Radio-Frequency Arrays For Ultra-High Field Mri, Ian R O Connell

Electronic Thesis and Dissertation Repository

Magnetic Resonance Imaging (MRI) is an indispensable, non-invasive diagnostic tool for the assessment of disease and function. As an investigational device, MRI has found routine use in both basic science research and medicine for both human and non-human subjects.

Due to the potential increase in spatial resolution, signal-to-noise ratio (SNR), and the ability to exploit novel tissue contrasts, the main magnetic field strength of human MRI scanners has steadily increased since inception. Beginning in the early 1980’s, 0.15 T human MRI scanners have steadily risen in main magnetic field strength with ultra-high field (UHF) 8 T MRI systems deemed to …

Clinical Applications Of Advanced Rotational Radiation Therapy, Adrian Nalichowski

Wayne State University Dissertations

Purpose: With a fast adoption of emerging technologies, it is critical to fully test and understand its limits and capabilities. In this work we investigate new graphic processing unit (GPU) based treatment planning algorithm and its applications in helical tomotherapy dose delivery. We explore the limits of the system by applying it to challenging clinical cases of total marrow irradiation (TMI) and stereotactic radiosurgery (SRS). We also analyze the feasibility of alternative fractionation schemes for total body irradiation (TBI) and TMI based on reported historical data on lung dose and interstitial pneumonitis (IP) incidence rates.

Methods and Materials: An anthropomorphic …

Radiation Therapy Medical Physics Review – Delivery, Interactions, Safety, Feasibility, And Head To Head Comparisons Of The Leading Radiation Therapy Techniques, Cielle Collins

Honors Theses and Capstones

Radiation therapy uses high energy radiation to kill cancer cells. Radiation therapy for cancer treatment can take the form of photon therapy (using x-rays and gamma rays), or charged particle therapy including proton therapy and electron therapy. Within these categories, numerous methods of delivery have been developed. For example, a certain type of radiation can be administered by a machine outside of the body, called external-beam radiation therapy, or by a “seed” placed inside of the body near cancer cells, called internal radiation therapy or brachytherapy. Approximately half of all cancer patients receive radiation therapy, and the form of radiation …

Development Of A Compact Broadband Optical Parametric Oscillator For Ultra-Sensitive Molecular Detection, Sean O. Crystal

Honors Undergraduate Theses

Every gas molecule has a unique absorption spectrum that can be captured using optical spectroscopy to identify an unknown sample's composition. Frequency combs systems can provide an extremely broad mid-infrared spectrum that is very useful for molecular detection. A degenerate optical parametric oscillator (OPO) was built to generate the down-converted and shifted frequency comb spectrum. This system utilizes an ultra-short pulse 1.56µm pump laser and a never before used orientation patterned gallium-phosphide crystal. Periodically polled lithium niobate (PPLN), Gallium Arsenide (GaAs) and Gallium Phosphide are all crystals used to accomplish this task. GaP, in comparison to PPLN, has (i) a …

Micro-Spectroscopy Of Bio-Assemblies At The Single Cell Level, Jeslin Kera

Honors Undergraduate Theses

In this thesis, we investigate biological molecules on a micron scale in the ultraviolet spectral region through the non-destructive confocal absorption microscopy. The setup involves a combination of confocal microscope with a UV light excitation beam to measure the optical absorption spectra with spatial resolution of 1.4 μm in the lateral and 3.6 μm in the axial direction. Confocal absorption microscopy has the benefits of requiring no labels and only low light intensity for excitation while providing a strong signal from the contrast generated by the attenuation of propagating light due to absorption. This enables spatially resolved measurements of single …