HP 129Xe MRI for Evaluation of CLAD in Lung Transplant Recipients

Hyperpolarized 129Xe Magnetic Resonance Imaging for Evaluation of Chronic Lung Allograft Dysfunction in Lung Transplant Recipients

To evaluate the feasibility of hyperpolarized 129Xe MRI in lung transplant recipients and assess structural and functional pulmonary changes using hyperpolarized 129Xe MRI

Lung transplantation is an effective treatment for end-stage lung disease. However, median survival post-LTx is 6 years. This is primarily due to chronic lung allograft dysfunction (CLAD).

Clinical management of LTx recipients is focused on identifying early risk factors for CLAD, by monitoring graft function with spirometry and transbronchial biopsies. However, both have significant limitations.

Hyperpolarized (HP) noble gas lung MRI (3He and 129Xe) allows mapping of both lung anatomy and function. 129Xe-MRI could provide a diagnostic tool that is able to detect CLAD more sensitively and earlier than the current gold standard measurements of spirometry and plethysmography, and thus allow a means to detect and prevent /slow down irreparable and irreversible damage to the lungs in the early stages of disease.

Inclusion Criteria:

• Patients, deemed clinically stable by the lung transplant team at UHN Toronto Lung Transplant Program (TLTP), 18 years of age or older
• Double lung transplant recipient
• For the 5 CLAD-free participants - at least 1 year of follow-up post-LTx and no substantial and persistent FEV1 decline (as per the ISHLT CLAD definition).
• For the 10 participants with CLAD - prior diagnosis of CLAD made by the clinical team (member of the TLTP).
• PFT measurements within 1 month of scan visit.
• FEV1 > 1.0 L

Exclusion Criteria:

• Currently pregnant or lactating
• Psychiatric or addictive disorders that would preclude obtaining informed consent or adherence to protocol
• Inability to travel to obtain MRI scan
• Any contraindications to MRI including but not limited to severe claustrophobia, implanted devices, aneurysm clips, neurostimulators (patients will be prescreened prior to registration).
• Baseline oxygen saturation of less than 88%.
• Requiring supplemental oxygen at baseline