Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Airspace opacification seen in the posterior basal aspect of the right lower lobe . Possible peribronchovascular opacification also seen in the right middle lobe . No parapneumonic effusion . No lymphadenopathy . Pulmonary scarring in the left upper lobe unchanged . Normal heart size .
    OUTPUT:
    
Right lower lobe pneumonia . Possible right middle lobe involvement .