Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is top - normal . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . Lung volumes are low however the lungs are clear . No pleural effusion or pneumothorax is seen . Mild vascular congestion without pulmonary edema .
    OUTPUT:
    
Low lung volumes . No evidence of acute intrathoracic injury .