Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low with vascular crowding but no focal airspace opacity . There is no pleural effusion or pneumothorax . Heart size is normal . The mediastinal and hilar contours are normal . There is no evidence of subdiaphragmatic free air .
    OUTPUT:
    
No evidence of subdiaphragmatic free air .