Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes . Right - sided IJV CVP has been removed . Stable mediastinal post CABG changes . Increased opacity in the left lower lobe , but this finding may be aggravated by the lower lung volumes . Small associated left - sided pleural effusion . Linear atelectasis seen in the lateral aspect of the left lower lung zone . Suspected small right - sided pleural effusion . No pulmonary edema . No pneumothorax . Spondylotic changes of the thoracic spine .
    OUTPUT:
    
Nonspecific opacification seen in the left lower lobe which shows interval progression compared to previous imaging and may represent atelectasis ( low lung volumes ) or developing pneumonia . Small associated left - sided effusion .