Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is persistent elevation of the left hemidiaphragm with associated layering parenchymal opacity suggestive of atelectasis , although somewhat decreased in extent . The lung volumes are low . There is no pleural effusion or pneumothorax . Mild degenerative changes are similar .
    OUTPUT:
    
Persistent elevation of the left hemidiaphragm and patchy associated atelectasis , but no definite evidence of pneumonia .