Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Heart size is mildly enlarged . Apparent widening of the mediastinal structures is likely due to low lung volumes . Old left - sided rib cage deformity is re - demonstrated as is an old right distal clavicular fracture and widening of the right acromioclavicular joint . There is crowding of the bronchovascular structures . There may be chronic blunting of the left costophrenic angle suggestive of pleural thickening although a trace effusion is not excluded . Retrocardiac opacity could reflect atelectasis but infection is not excluded . No pneumothorax is seen .
    OUTPUT:
    
Low lung volumes . Possible patchy retrocardiac opacity reflecting atelectasis but infection is not excluded . Remote osseous deformities of the thorax and right AC joint separation likely from prior trauma .