Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest provided . Retrocardiac opacity with an air - fluid level is compatible with known hiatal hernia . There is a small right pleural effusion . The lungs appear clear without convincing sign of pneumonia or overt edema . Cardiomediastinal silhouette appears within normal limits . No acute osseous abnormality .
    OUTPUT:
    
Hiatal hernia , small right pleural effusion . No overt edema or pneumonia .