Figure 6.

Pulmonary vascular remodeling. Vascular tree rendering showing vascular pruning across Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages. Panels show anterior views of the vascular tree color coded by vessel diameter from small (red to orange) to medium (yellow to green) to large (green to blue) vessels. (A) A 58-year-old female current smoker with GOLD stage 1 (FEV₁ % predicted, 85%) with mild emphysema (low-attenuation area percentage [LAA%], 6.0%). The vascular analysis shows a ratio of blood volume for vessels less than 5 mm² (BV5) to total blood volume of 0.58 (BV5 was 104.7 ml, and total blood volume was 179.6 ml). (B) A 66-year-old female former smoker with GOLD stage 2 (FEV₁ % predicted, 67%) with moderate emphysema (LAA%, 11.3). The vascular analysis shows apparent pruning in the peripheral vasculature with a ratio of BV5 to total blood volume of 0.53 (BV5 was 104.7 ml, and total blood volume was 179.6 ml). (C) A 77-year-old male with GOLD stage 3 (FEV₁ % predicted, 30.1%) with mild emphysema (LAA%, 8.5%). The ratio of BV5 to total blood volume is 0.5 (BV5 was 108.8 ml, and total blood volume was 218.2 ml), showing a diffuse vascular pruning. (D) A 46-year-old male with GOLD stage 4 (FEV₁ % predicted, 29.3%) with upper lobe emphysema (LAA%, 25.8%). The vascular analysis shows pruning in upper lobes with a ratio of BV5 to total blood volume of 0.46 (BV5 was 104.4 ml, and total blood volume was 227.5 ml).