19F MRI in Healthy Children and Children With Mild Cystic Fibrosis Lung Disease

A Cross-sectional Pilot Study of 19F MRI in Healthy Children and Children With Mild Cystic Fibrosis Lung Disease

This study capitalizes on the emerging technology of 19F MRI, using conventional 'thermally' polarized perfluorinated gas (perfluoropropane, or PFP) mixed with oxygen and studied with magnetic resonance imaging (MRI) to visualize ventilation. This technique has not been studied in children.

Children and adolescents (6-17 years old) with cystic fibrosis (CF) who have normal spirometry will undergo 19F MRI with the inhalation of an inert contrast gas to study ventilation. Comparisons will be made to a cohort of healthy children (6-17 years old) who will perform the same measures. The primary outcome measure is the feasibility of conducting these studies in the pediatric population. Parallel performance of multiple breath nitrogen washout (MBW) and spirometry will be used to compare the sensitivity of these outcomes to the presence of mild lung disease in these children. Finally, the investigators will compare data obtained during standard breath holds with a novel "free-breathing" technique that will eliminate the need for breath holds during MRI acquisition.

Inclusion Criteria:

• 6-17 years old
• Non-smoker and non-vaper
• Cystic Fibrosis (CF) Group: must have a diagnosis of CF
• No use of supplemental oxygen
• They must be able to perform spirometry and have stable lung function (within 10% personal best in the last 6 months) and no exacerbations within the past 4 weeks
• Baseline forced expiratory volume in 1 second (FEV1) >80% with ratio of the forced expiratory volume in the first one second to the forced vital capacity of the lung (FEV1:FVC) ratio >0.7

Exclusion Criteria:

• Healthy volunteers: with any history of chronic lung disease (i.e. asthma)

• Active or former smoker with less than 1 year of quitting

• Unable to undergo an MRI of the lungs and chest because of contraindications, including:

  • Injury to the eye involving a metallic object
  • Injury to the body involving a metallic object
  • Presence of an implanted drug infusion device that is not MRI safe
  • Bone growth of fusion simulator
  • Presence of cochlear, otologic, or ear implant
  • Shunt (spinal or intraventricular)
  • Any implant held in place by magnet
  • Claustrophobia

• Unable to tolerate the inhalation of the gas mixture

• Facial hair preventing a tight fit of the mask used in the study

• Pregnancy

• Changes in medication that may affect CF lung disease or lung function in the past 28 days, including experimental therapies