Electronic Thesis and Dissertation Repository


Master of Science


Medical Biophysics


Grace Parraga


Diffusion-weighted magnetic resonance imaging (MRI) provides unparalleled information and measurements of lung structure and function without the burden of ionizing radiation. In particular, diffusion-weighted MRI provides estimates of airspace enlargement, which is a hallmark characteristic of emphysema. MRI provides a way to measure in vivo mean-linear-intercept (Lm) and this is a promising measurement for clinical evaluation of disease progression in patients with Alpha-1 Antitrypsin Deficiency (AATD) in which airspace enlargement begins early in life. As such, our objective was to evaluate MRI measurements of airspace enlargement in AATD patients and compare these measurements to ex-smokers with chronic obstructive pulmonary disease (COPD) and healthy never-smokers. We compared these measurements with standard clinical measurements provided by spirometry, plethysmography and computed tomography; we also demonstrated that MRI detected differences in disease severity in patients with clinically similar measurements.