Assessment of Lung Movement With Computed Tomography (CT)

The purpose of this study is to determine whether patient with ILD have altered lung compliance on chest CT before they have macroscopic structural changes on CT.

Interstitial lung disease (ILD) is a group of lung disorders in which the lung tissues become inflamed and then damaged. Idiopathic Pulmonary Fibrosis (IPF) is one of the subtypes of ILD which has characteristic histological and CT features. It is well known that microscopic fibrosis occurs in the lungs of IPF patients well before the structural changes of fibrosis become apparent on CT. By combining sophisticated image analysis with CT scans obtained at full inspiration and full expiration, it may be possible to detect earlier changes of IPF than currently possible by looking at macro structural features alone. With the recent development of new therapeutics for IPF, early detection of the disease and improved monitoring of treatment efficacy will become important. Using CT to assess regional lung compliance has the potential to become an easily translated clinical tool.

A computer algorithm will compare the inspiration and expiration CT scans to determine regional lung motion.

Lobar strain (S): the volumetric strain of each lobe i [i = Right Upper (RU), Right Lower (RL), Left Lower (LL), and Left Upper (LU)] as the difference in lobe volume between the expanded and contracted states, normalized by the lobe volume in the expanded state

Inclusion Criteria: Subjects with ILD: Subjects must have a physician diagnosis of ILD and be in stable pulmonary condition at the time of the CT Healthy subjects: Subjects must have no history of pulmonary disease and smoked less than 100 cigarettes in their lifetime Exclusion Criteria: Subjects less than 18 years of age