Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . Lung volumes are low . Heart size and cardiomediastinal contours are normal . There is mild pulmonary edema with bibasilar atelectasis . Ill - defined left lower lobe opacity could be atelectasis or infection . No substantial pleural effusion or pneumothorax is appreciated .
    OUTPUT:
    
Mild pulmonary edema with low lung volumes . An underlying infection is difficult to exclude .