CFTR and cystic fibrosis: This MRI score was shown to be robust and reproducible in single-and multicenter observational studies and to be sensitive to detect lung abnormalities across a broad age range of clinically stable patients with CF from infancy to adulthood (10, 11, 18), acute changes associated with pulmonary exacerbations (9), and response to therapeutic interventions including antibiotic therapy for pulmonary exacerbation, as well as cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies (13, 19, 20).