Axial chest CT scans (IMAGE) Radiological Society of North America Caption Axial chest CT scans at (A) visit 1 and (B) visit 2 at the level of the takeoff of the right middle bronchus of a participant with 1.2 annual percentage quantitative interstitial abnormality progression. The female participant was 62 years old at visit 1 and 67 years old at visit 2 and a current smoker at both visits, with a 47.5 pack-year history at visit 2. This participant had four subsequent acute respiratory disease (ARD) events and three subsequent severe ARD events. Credit Radiological Society of North America (RSNA) Usage Restrictions May use with credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.