Figure 3. Rib cage morphometric differences between a normal 58-year-old male smoker (A) and a 61-year-old male COPD patient with severe emphysema (B).

Both detailed measurements and the 3D reformation display the main morphologic differences: larger upper rib cage dimensions and smaller lower rib cage dimensions in COPD. Overall, the morphometric changes in COPD contribute to the “barrel chest” configuration.