Assessment of Chronic Lung Allograft Dysfunction Using Single-breath & Multi-breath Hyperpolarized Xenon-129 MRI
brief summary
This study will use Magnetic Resonance Imaging (MRI) to study the lungs of 90 volunteers using the inhaled contrast agent, hyperpolarized xenon-129. Once inhaled, this gas can provide information to imagers regarding lung functionality across specific regions of the lungs by assessing the replacement of air during the normal breathing cycle, how much oxygen is in the airspaces, and if the natural spongy tissue structure has been compromised by lung disease. Of the 90 subjects, 70 will be patients who received lung transplantation from the Penn/Temple Lung Transplant Teams and are receiving follow up treatment at HUP or TUH, 10 will be healthy control subjects who participated favorably in our HP 129Xe imaging protocol, and 10 will be patients who have been diagnosed with chronic obstructive pulmonary disease (COPD)-preferentially recruited from the Temple University COPDGene cohort, who have never undergone a lung transplant. 20 of the lung transplant recipient subjects will be patients who have received a recent clinical diagnosis of chronic lung allograft dysfunction (CLAD) prior to enrollment in our study, while the other 50 will have recently undergone their initial transplant surgery at the time of enrollment.
detailed description
This study assesses the operating characteristics of HP 129Xe MRI in an effort to evaluate its performance in identifying early signs of CLAD or graft acceptance in 70 total lung transplant recipients, 20 of whom have been recently diagnosed with CLAD, 10 non-transplant COPD subjects, and 10 healthy control patients. These subjects will be recruited from the patients of transplant pulmonologists on the Penn and Temple Lung Transplant Team. Subjects will be recruited regardless of race or gender. Study visits will last 1-2 hours for each subject and will occur at various time points following their operation. The baseline visit will occur at the conclusion of their 3 month post-transplant visit, with study follow-up visits occurring at the conclusion of the 6, 9, 12, 18, and 24 month post-transplant visit. For the convenience of the subjects, most study visits will begin at the conclusion of their follow-up visit with their transplant pulmonologist. If this does not work for the subject, an alternative date will be scheduled and the PFT's/Physical exam results from the most recent visit with their transplant pulmonologist will be used for that study visit. There will be a 45-day imaging window for each post-transplant visit, allowing MR imaging to be performed within 45 days before or after the anticipated imaging date, granting more flexibility for both subjects and researchers to ensure that each imaging session is successfully completed. If patients decide to not participate in this study, their decision will not affect their standing with HUP or their physician. Both healthy control subjects and non-transplant COPD subjects will be imaged twice within approximately one week to ensure imaging metric reproducibility in both cohorts. Diagnosed CLAD subjects will undergo a single imaging session each. The images of the diagnosed CLAD subjects will serve as a necessary reference for predicting the early decline of lung function in pre-CLAD transplant recipients.