Motion resolved reconstructions, using compressed sensing, of 3D ultra short echo time (UTE) acquisitions in cystic fibrosis patients were performed. The definition of the lung-liver interface was quantified and found to be significantly higher than that in motion corrupted reconstructions of the whole datasets. The Helbich-Bhalla score for cystic fibrosis was determined using both computed tomography (CT) and MRI data. Correlation between scores obtained with both modalities was good (ρ=0.77) but consistency was moderate (ICC=0.62). This was due to average MRI scores being lower by 15%, most likely because mosaic perfusion could not be assessed with MRI.