Advances in Imaging Cystic Fibrosis Lung Disease

Cystic fibrosis (CF) is a life shortening, multiorgan disease, in which morbidity and mortality are dominated by pulmonary pathologies, including mucous obstruction, chronic lung infections, progressive bronchiectasis, and declining lung function. Promising new therapies, including those that target the cystic fibrosis transmembrane conductance regulator (CFTR) protein, have shown impressive efficacy in treating CF patients with specific genotypes. While spirometry is the clinical gold standard for evaluating CF lung disease, it has known insensitivities to mild lung disease and statistical weaknesses in small cohorts. Imaging has begun to play an important role in evaluating the structural abnormalities associated with CF lung disease progression. X-ray computed tomography (CT) has been established as a modality with validated metrics to evaluate disease severity, even in young patients with mild disease. Magnetic resonance imaging (MRI), as a nonionizing alternative, has very strong potential for similar metrics and longitudinal use through the lifespan. In this brief review, recent advancements in imaging CF lung disease in pediatrics are discussed, specifically in the contexts of X-ray CT, ultra-short echo time MRI, and hyperpolarized-gas MRI, with an emphasis on how emerging techniques will likely impact the management of CF lung disease in the era of CFTR-modulator therapies, targeted at smaller subpopulations of CF with specific genotypes. In the future, techniques that provide sensitive, quantitative measurements of regional lung structure and function longitudinally will become increasingly important as outcome measures for clinical trials and for monitoring individual CF patients.