Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A trauma board slightly limits evaluation of this radiograph . Lung volumes are low , causing exaggeration of the heart size and accentuation of the pulmonary vasculature . There is minimal bilateral lower lung atelectasis . The lungs are otherwise clear . There are no definite pleural effusions . No pneumothorax is seen . The heart is normal in size . Apparent widening of the superior mediastinum relates to mediastinal fat , as seen on subsequent CT .
    OUTPUT:
    
No acute cardiac or pulmonary process .