UBC Theses and Dissertations
Use of CT and MicroCT to quantify structures in human lungs McDonough, John Edward
MicroCT is a technology that allows for obtaining images with resolution equivalent to histological sections from volumes of tissue that would be prohibitive to examine by classical sectioning techniques. In this dissertation, three studies are reported that make novel use of microCT to quantify structures within lung tissue. In the first study, microCT was used to quantify the number of alveoli within normal human lungs. The data show that alveolar number can vary throughout the lung with more alveoli per volume of lung present in the apex of the lung compared to the base. In the second study, airway dimensions from normal human lungs and lungs from patients with advanced COPD were measured on microCT images and compared to measurements made on the same airways obtained using lower resolution MDCT images. These measurements confirmed that MDCT overestimates measurements of the airway wall and underestimate measurements of the airway lumen. As well, microCT was able to show a correlation of airway wall thickness to the extent of emphysema within the lung but no correlation was found when measurements from MDCT were used. This suggests that microCT is able to detect more subtle changes in the airway wall dimensions that MDCT could not. In the third study, microCT was used to quantify the numbers and lumen area of terminal bronchioles in normal human lungs and lungs from patients with advanced COPD. We found that terminal bronchiole dimensions and number from normal lungs were similar to the classical data. As well, we found a marked reduction in the number of terminal bronchioles and a narrowing of the lumen of these airways in the lungs of patients with COPD. Remarkably, we found these changes occurred in regions of the lung with minimal emphysematous destruction, suggesting that these changes occur before parenchymal destruction takes place. These three studies show that microCT is an important and underutilized imaging technology to examine the lung and its use will likely be expanded in futures studies to examine the pathological changes that occur in the tissue structure of other lung diseases.
Item Citations and Data
Attribution-NonCommercial-NoDerivatives 4.0 International