Emphysema Centrilobular emphysema 2020-04-25T12:44:03Z Centriacinar emphysema A type of emphysema characterized by destroyed centrilobular alveolar walls and enlargement of respiratory bronchioles and associated alveoli. This is the commonest form of emphysema in cigarette smokers. CT findings are centrilobular areas of decreased attenuation, usually without visible walls, of nonuniform distribution and predominantly located in upper lung zones.