Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The mediastinal and hilar contours appear within normal limits . There may be a trace pleural effusion on the left side . The left posterior costophrenic sulcus is partly excluded on the lateral view making it difficult to exclude a trace pleural effusion . No fracture is identified .
    OUTPUT:
    
No evidence of acute disease .