Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Please take note of the low lung volumes . There has been interval progression of the bibasal airspace opacification over serial radiographs . No associated large effusion . The heart size is normal . Right - sided PICC line in situ with the tip in the distal SVC . The upper lung zones are clear .
    OUTPUT:
    
Interval progression of the bibasal airspace opacification which is nonspecific , but most likely represents a combination of atelectasis and pneumonia