Original ArticleUse of hyperpolarized helium-3 MRI to assess response to ivacaftor treatment in patients with cystic fibrosis

BackgroundThis pilot study evaluated the effect of short- and long-term ivacaftor treatment on hyperpolarized 3He-magnetic resonance imaging (MRI)-defined ventilation defects in patients with cystic fibrosis aged ≥ 12 years with a G551D-CFTR mutation.MethodsPart A (single-blind) comprised 4 weeks of ivacaftor treatment; Part B (open-label) comprised 48 weeks of treatment. The primary outcome was change from baseline in total ventilation defect (TVD; total defect volume:total lung volume ratio).ResultsMean change in TVD ranged from − 8.2% (p = 0.0547) to − 12.8% (p = 0.0078) in Part A (n = 8) and − 6.3% (p = 0.1953) to − 9.0% (p = 0.0547) in Part B (n = 8) as assessed by human reader and computer algorithm, respectively.ConclusionsTVD responded to ivacaftor therapy. 3He-MRI provides an individual quantification of disease burden that may be able to detect aspects of the disease missed by population-based spirometry metrics. Assessments by human reader and computer algorithm exhibit similar trends, but the latter appears more sensitive.www.clinicaltrials.gov identifier: NCT01161537