Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is top normal and unchanged . The mediastinal and hilar contours are stable and within normal limits . The pulmonary vascularity is not engorged . A trace left pleural effusion is likely present . There is minimal bibasilar atelectasis . No pneumothorax is present , and no acute osseous abnormalities seen .
    OUTPUT:
    
Small left pleural effusion and mild bibasilar atelectasis .