Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are a few opacities in the left lung base with increased density over the lower thoracic spine on the corresponding lateral view , which appear slightly linear . No pleural effusion or pneumothorax is present . The pulmonary vasculature is essentially within normal limits . The cardiomediastinal and hilar contours are also within normal limits . A right healed rib fracture is incidentally noted .
    OUTPUT:
    
Opacities in the left lower lobe may represent atelectasis although early developing pneumonia is not entirely excluded .