Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are well expanded . A 2 mm nodular opacity in the left upper lung likely represents a granuloma or vessel en face . The lungs are otherwise clear . The cardiomediastinal silhouette , hilar contours , pleural surfaces are normal . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Normal radiograph of the chest .