Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiomediastinal contours are unchanged , with stable appearance of a large tortuous thoracic aorta . The lungs demonstrate opacity in the right base which appears similar to ___ but increased from ___ . There may also be a trace pleural fluid on the right . The left lung is clear . There is no pneumothorax .
    OUTPUT:
    
Right lower lung opacity , with trace pleural fluid ; in the appropriate clinical setting may represent pneumonia .