Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is within normal limits . The mediastinal and hilar contours appear normal . The lungs demonstrate a linear opacity in the left lower lobe which may represent scarring , atelectasis , or less likely pneumonia . There is no pleural effusion or pneumothorax . Minimal degenerative change seen in the thoracic spine .
    OUTPUT:
    
Equivocal evidence for pneumonia - more likely left lower lobe atelectasis or scarring .