Fig. 1From: Functional respiratory imaging in relation to classical outcome measures in cystic fibrosis: a cross-sectional studyIllustration of FRI parameters: A air trapping, B airway volume at TLC, C pulmonary vessels with a cross-sectional area < 5 mm2, 5–10 mm2 and > 10 mm2, respectively coloured in red, yellow and blueBack to article page