Fig. 2

Topological strain contour maps of representative porcine lung at varying breathing rates of 10, 15, and 20 breaths per minute and inflation volumes of 675 ml, 900 ml, and 1350 ml at the maximum inflation stage. As the applied volume increased, surface strain heterogeneity became more prominent as indicated by appearance of regional high strain concentrations in the upper caudal left lung lobe and middle lobe of the right lung. The influence of breathing rate on local strains was not observed to be unidirectional