Quantification of the tissue changes in the human lung with chronic lung disease using a combination of computed tomography and stereology

• Main Author: Coxson, Harvey Owen
• Format: Others
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/8475

Idiopathic pulmonary fibrosis (IPF) and pulmonary emphysema are chronic lung diseases exhibiting progressive deterioration in pulmonary function as the lung architecture is remodeled. This thesis quantifies these tissue changes using a novel combination of computed tomography (CT) and quantitative histology. Pre-operative CT scans were obtained from patients with IPF, patients receiving lung volume reduction surgery for diffuse emphysema and from patients with minimal to mild emphysema undergoing lobectomy for a small peripheral tumour. Total lung volume was calculated using the pixel dimensions on the CT scan while airspace and tissue volume as well as the regional lung expansion were estimated using the attenuation values. Tissue samples were obtained at either open lung biopsy (IPF) or surgical resection (control and emphysema) and prepared for quantitative histology. A method for correcting the histology specimens to an in vivo level of inflation was developed so that tissue composition and surface area could be estimated using stereologic techniques. The data shows that there is a reorganization of lung parenchyma in IPF with a disproportionate of airspace and surface area without increasing the total amount of tissue. The patients with emphysema show evidence of a progressive proteolytic destruction of tissue volume and surface area. There is a negative correlation between regional lung expansion and surface area in emphysema and a positive correlation between surface area and the diffusing capacity of the lung in both diseases. This technique should prove useful in the longitudinal assessment of chronic lung diseases and the monitoring of response to treatment. === Medicine, Faculty of === Medicine, Department of === Experimental Medicine, Division of === Graduate