Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable chest radiograph demonstrates low lung volumes , as before . The heart size is enlarged but stable , and the mediastinal contours are enlarged but stable . The lung parenchyma is clear with a small amount of atelectasis at the lung bases . There is no pleural effusion or pneumothorax . There is no evidence of pulmonary edema .
    OUTPUT:
    
Low lung volumes with no evidence of pulmonary edema .