We have developed a fully automated 3D CT-image segmentation method that separates each lung from the trachea-bronchi, in order to study abnormalities on the pleura and interior of the lungs. Lung separation in this case is important to investigate abnormal lung asymmetries. The detection of pleural plaques derived from asbestos is an example. As shown in the cover image, it is possible to visualize them and even segment them interactively for quantification and analysis.