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Full-Text Articles in Analytical, Diagnostic and Therapeutic Techniques and Equipment

Feasibility Of Using Arterial Spin Labeling For Detecting Longitudinal Changes In Cerebral Blood Flow, Tracy Ssali Oct 2015

Feasibility Of Using Arterial Spin Labeling For Detecting Longitudinal Changes In Cerebral Blood Flow, Tracy Ssali

Electronic Thesis and Dissertation Repository

The ability of the perfusion MRI technique, arterial spin labeling (ASL), to quantify cerebral blood flow (CBF) makes it attractive for longitudinal studies of changes in brain function, such as those related to chronic pain. However, ASL's poor spatial resolution makes image alignment between sessions difficult, leading to increased variance and greater Type-I errors. In addition, variability due to differences in basal blood flow between sessions and confounding effects such as the arterial transit time (ATT) have the potential to reduce reproducibility over time. The focus of this thesis is to investigate the ability of ASL to detect long-term changes …


Hyperpolarized 129xe Magnetic Resonance Imaging Of Radiation-Induced Lung Injury, Ozkan Doganay Oct 2015

Hyperpolarized 129xe Magnetic Resonance Imaging Of Radiation-Induced Lung Injury, Ozkan Doganay

Electronic Thesis and Dissertation Repository

Lung cancer is the largest contributor to cancer-related mortality worldwide. Only 20% of stage III non-small cell lung cancer patients survive after 5-years post radiation therapy (RT). Although RT is an important treatment modality for lung cancer, it is limited by Radiation-Induced Lung Injury (RILI). RILI develops in two phases: (i) the early phase (days-weeks) referred to radiation pneumonitis (RP), and (ii) the late phase (months). There is a strong interest in early detection of RP using imaging to improve outcomes of RT for lung cancer. This thesis describes a promising approach based on 129Xe gas as a contrast …


Non-Invasive Quantification Of Alveolar Morphometry Measurements In Older Never-Smokers, Gregory A. Paulin Apr 2015

Non-Invasive Quantification Of Alveolar Morphometry Measurements In Older Never-Smokers, Gregory A. Paulin

Electronic Thesis and Dissertation Repository

Diffusion-weighted noble gas pulmonary magnetic resonance imaging (MRI) provides in vivo images with a contrast uniquely sensitive to molecular displacement at cellular and sub-cellular length scales. We estimated the external airway radius (R) and internal airway radius (r) of the alveolar dimensions to evaluate potential differences in acinar duct morphometries in healthy older never-smokers and compared those with a group of ex-smokers. The acinar duct and alveolar MRI morphometry results were within the physiologically-valid range of parameters. Estimated values of internal (r) and external (R) airway radius as well as alveolar sheath (h) and …