Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest provided . There is retrocardiac density with air - fluid levels compatible with known hiatal hernia . The lungs are clear without signs of aspiration or pneumonia . No pleural effusion or pneumothorax is seen . Heart and mediastinal contours are normal . Bony structures are intact .
    OUTPUT:
    
Hiatal hernia again seen . Otherwise , normal .