Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lung volumes are low . The cardiac , mediastinal and hilar contours appear unchanged . There are plate - like opacities in the lower lungs suggesting atelectasis . A large pulmonary nodule is visible at the right lung base and has been characterized previously . There no pleural effusions or pneumothorax .
    OUTPUT:
    
Patchy atelectasis and similar nodule at the right base . Evaluation for any potential small change is limited , however . No evidence of pneumothorax .