Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest provided . Tip the lungs are clear bilaterally . A retrocardiac opacity with an air - fluid level is consistent with a moderate hiatal hernia . The heart is mildly enlarged . The mediastinal contour is normal . No signs of congestion or edema . No large effusion or pneumothorax . The imaged bony structures are intact . No free air seen below the right hemidiaphragm .
    OUTPUT:
    
Hiatal hernia , otherwise unremarkable .