Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiomediastinal and hilar contours are within normal limits . The aorta is tortuous . There is bilateral apical bronchial thickening , as before . Lung volumes are lower on the current study . Focal opacity involving the right lower lobe could represent an area of atelectasis or infection . There is no effusion or pneumothorax .
    OUTPUT:
    
Subtle opacity in the right lower lobe could represent atelectasis or infection in the appropriate setting .