Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral radiographs demonstrate a minimal left lower lobe opacity , similar to the prior radiographs . This likely represents atelectasis . The lungs are otherwise clear . The hilar and cardiomediastinal contours are normal . There is no pneumothorax or pleural effusion . Pulmonary vascularity is normal .
    OUTPUT:
    
Minimal left basilar atelectasis , similar to the prior study . No evidence of pneumonia .