Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph obtained . The lung volumes are low . There is very subtle opacity at the medial right lung base which could represent a confluence of bronchovasculature though in the correct clinical setting an early consolidation is difficult to exclude . Elsewhere , the lungs are clear . The heart and mediastinal contour appears normal . The imaged osseous structures appear intact .
    OUTPUT:
    
A subtle opacity in the medial right lung base which could represent a very subtle pneumonia . Otherwise normal .