Vibration Response Imaging (VRI) in Lung Transplant Recipients

* Study participants will be patients who have undergone lung transplantation during the last 6 months and are in a stable clinical position at the time of enrollment. * Patients who meet the study inclusion and exclusion criteria will be enrolled in the study. * The enrolled patients will be recorded with the VRI at each occurrence in which the standard procedures are performed:

* Baseline after study enrollment (VRI Recording 1 + standard evaluations). * At each follow-up visit \[1, 3, 6 months after baseline visit\] during the 6 month follow-up period of the study (VRI Recordings + standard evaluations (if possible)). * In the event of bronchoscopic intervention, then before the interventional procedure (VRI Recording 1 + standard evaluations) and before any recurrent interventional procedures (VRI Recordings + standard evaluations) during the course of the study (6-month follow-up period). * 1 hour after all bronchoscopic interventional procedures. * In the event of an unanticipated visit, then a VRI recording will be performed (VRI Recordings + standard evaluations). * All subjects will be recorded according to a standard procedure; moreover, it is essential that for each subject repeatable recordings will be performed in the same manner (i.e. breathing manner and matrix placement). Each VRI recording session will take \~15 minutes \[the actual recording is \~2 minutes for placement and breathing/recording\]. * Standard evaluation procedures may include any of the following:

* Lung function tests (this test is required at all visits) * Physical examination * Bronchoscopy (e.g. transbronchial biopsy) * CT-imaging * Chest x-ray * V/Q Scan (Baseline visit for single lung transplantation) * Blood gases (this test is required at all visits) * Blood tests