The goal of this study is to evaluate the usefulness of hyperpolarized (HP) 129Xe (xenon) gas MRI for regional assessment of lung function in a normal population of adults for the purposes of obtaining optimal images through MRI.

Hyperpolarized 129Xe will be produced, by trained staff, using a polarizer housed at Cincinnati Children's Hospital Medical Center. Individual imaging sessions will be done on a single day and will involve administration of (maximum) 1 liter doses for up to four MRI scans. Subject will inhale hyperpolarized xenon gas and hold breath for up to 16 seconds during the MRI scans. In addition to 129 Xe MRI, a series of anatomical conventional proton MR images may also be collected. Follow up will be done one day and 30 days from the MRI date.

Inclusion Criteria:

• Adults ages 18 years and older
• Participant must be able to hold their breath for up to 16 seconds

Exclusion Criteria:

• History of heart defect
• Pregnancy or positive pregnancy test
• History of uncontrolled asthma defined for this study as requiring use of rescue inhaler ≥ 2 times in past month.
• Symptoms of respiratory infection (loose or productive cough or wheeze), chest tightness, or sinus infection within past week.
• Baseline oximetry at MRI visit of less than 95% on room air or less than 95% on a previously prescribed dosage of oxygen delivered by nasal cannula.
• Participant is claustrophobic and unable to tolerate the imaging.
• Standard MRI exclusions (metal, implants).