Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac , mediastinal and hilar contours are unchanged and within normal limits . Pulmonary vasculature is normal . Lungs remain hyperinflated . Patchy and linear opacities within the lung bases likely reflect areas of atelectasis and / or scarring . No focal consolidation , pleural effusion or pneumothorax is present . No acute osseous abnormality is detected .
    OUTPUT:
    
Bilateral lower lobe atelectasis and / or scarring . No radiographic evidence for pneumonia .