Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are relatively low lung volumes . Bilateral perihilar and lower lobe opacities may relate to patient 's chronic lung disease however , superimposed infection are mild edema is not excluded . More focal right mid lung opacity is seen , new since the prior chest radiograph , and infectious process could be present . No pleural effusion or pneumothorax . Stable cardiac and mediastinal silhouettes .
    OUTPUT:
    
Low lung volumes and chronic lung disease . More focal patchy opacity in the right mid lung new since the prior chest radiograph , could represent a site of infection .