A quantification of the lung surface area in emphysema using computed tomography

Quantitative analysis of computed tomography (CT) has been combined with a stereologically based histologic analysis of lung structure to assess regio nal lung inflation and the structural features of the lung parenchyma. In t his study, CT measurements of lung inflation were compared with histologic estimates of surface area in order to develop prediction equations that all ow lung surface to volume ratio and surface area to be predicted from an an alysis of the CT scan. The results show that mild emphysema is associated w ith an increase in lung volume and a reduction in surface to volume ratio, whereas surface area and tissue weight were only decreased in severe diseas e. The CT predicted surface to volume ratio correlated with histology, and both predicted and measured surface areas correlated with the diffusing cap acity. We conclude that this CT analysis can be used to monitor the progres sion of emphysematous lung destruction in individual patients, and to asses s the impact of both surgical and medical treatments for emphysema.