Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compare to ___ , lung volumes are low , accentuating the heart size and interstitial opacities . Bibasilar opacities obscuring the diaphragms are likely due to atelectasis , though pneumonia can not be excluded . Small left pleural effusion is likely . The mediastinum and the hilar contours are unremarkable . Left - sided VP shunt is seen .
    OUTPUT:
    
Possible left lower lobe pneumonia .