Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is mildly enlarged . There is a moderate hiatal hernia with an air - fluid level . The mediastinal and hilar contours appear unchanged aside from the fact that the hiatal hernia was quite small before in retrospect , so it may be partly reducible . The lungs appear clear . There are no pleural effusions or pneumothorax . Bony structures are unremarkable .
    OUTPUT:
    
Moderate hiatal hernia . No evidence of acute disease .