This studies purpose is to confirm the efficacy and efficiency of using OE-MRI and MRI with hyperpolarized gas techniques and Iodinated contrast CT scan, this will enhance understanding of CLAD pathophysiology. Moreover, this project is foundational to performing additional studies to establish if novel MRI imaging can serve as an objective confirmatory diagnostic tool for CLAD in post-transplant patients.

This studies purpose is to confirm the efficacy and efficiency of using OE-MRI and MRI with hyperpolarized gas techniques and Iodinated contrast CT scan, this will enhance understanding of CLAD pathophysiology. Moreover, this project is foundational to performing additional studies to establish if novel MRI imaging can serve as an objective confirmatory diagnostic tool for CLAD in post-transplant patients.

This observational imaging study will use 3T UTE MRI with varying oxygen levels (room air vs. 100% oxygen) to evaluate lung ventilation using oxygen enhanced imaging, in 50 healthy normal subjects (age 18-80).

Subjects will have vital signs taken, complete questionnaires and have pulmonary function test (spirometry) done, Iodinated contrast CT scan and standard of care CT scans, in addition to one MRI session that will include 6 series of scans. The MRI scans will be taken in supine position (laying on back) and include breathing room air and 100% oxygen. OE-MRI will be done in addition to MRI scans with Xenon-129.

All subjects-Inclusion Criteria:

• Ages 18-80
• English Speaking Subjects
• Willingness and ability to provide informed consent
• Non-smoker

Lung transplant patients-inclusion criteria:

• >/= 6 months from lung transplant
• History of bilateral lung transplant

CLAD-free patients-inclusion criteria:

• Stable spirometry with FEV1 > 90% of baseline value (average of 2 best values) and forced mid-expiratory flow (FEF) (25-75) > 75% of baseline
• Total Lung Capacity (TLC) > 90 % of baseline
• Post-transplant chest radiograph without significant abnormality
• No evidence of on-going lung infection or allograft rejection

Early CLAD patients-inclusion criteria:

• FEV1 < 80% of baseline value (average of 2 best values)
• Follow up 6-months or decline in lung function (20% decrease in FEV1 without evidence of infection or acute rejection)

Exclusion Criteria:

• SAO2 drops below 90% (in absence of mechanical failure) during normal tidal breathing
• Unilateral diaphragm paralysis
• Evidence of acute illness on day of study
• Evidence of restrictive lung disease
• Dependence on supplemental oxygen
• History of cardiac disease
• Pregnancy (self-declared)
• Lactating women
• Participants with metal objects in their body
• Known contraindication to MRI examination
• Systolic blood pressure reading of < 100 mmHg or > 200 mmHg
• Diastolic blood pressure reading of <60 mmHg or > 100 mmHg