Figure 3.

Accuracy of extrapolation for assessing changes of lung volume and masses between consecutive CTs. The accuracy of the extrapolation method for assessing changes (delta) of lung volume and masses between consecutive CTs was analyzed by the Bland-Altman method in 58 pairs of consecutive CTs. The solid red line indicates the mean difference between whole-lung CT analysis and extrapolation (bias). The dashed lines indicate the 95% limits of agreement. Delta_all, changes of quantitative CT parameters (total lung volume and mass, mass of differently aerated lung compartments) between two consecutive CTs assessed by whole-lung analysis; Delta_extra , changes of parameters between two consecutive CTs calculated by extrapolation; g, grams; ml, milliliters.