Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The mediastinal and hilar contours are unremarkable . There is no pleural effusion or pneumothorax . There is a vague suspected posterior opacity probably in the left lower lobe and superimposed over the spine and left hemidiaphgram ; elsewhere the lungs appear clear . Mild degenerative changes are noted along the thoracic spine .
    OUTPUT:
    
Suspected patchy posterior opacity , not specific and probably compatible with atelectasis ; pneumonia or even a lung nodule is not excluded , however , and correlation with planned CT is suggested .