Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since the prior examination , there is worsening of mild left basilar atelectasis . The remainder of the lungs are clear . There are no focal opacities concerning for pneumonia . There are no pleural effusions or pneumothorax . Cardiomediastinal and hilar contours are stable demonstrating marked tortuosity of the thoracic aorta .
    OUTPUT:
    
No evidence of pneumonia . Interval development of left basilar atelectasis .