Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are low lung volumes . The right lung is clear . A dense retrocardiac opacity suggests left lower lobe atelectasis . Linear opacities across the left lung field represent discoid atelectasis , but no new confluent consolidations are noted in the left lung . The heart size is top normal , although assessment is limited in this AP radiograph . Cardiomediastinal and hilar contours are unremarkable . There is no pleural effusion or pneumothorax . Again seen is a Port - A - Cath catheter with the tip ending at the level of the lower SVC . There is no evidence of abdominal free air .
    OUTPUT:
    
Left lower lobe atelectasis . No evidence of abdominal free air .