Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are slightly low with a mildly elevated right hemidiaphragm . There is a patchy area of atelectasis in the left lower lung but no definite infiltrate . The upper lungs are clear . The heart is upper limits normal in size . The spine shows some mild degenerative changes . There is no effusion .
    OUTPUT:
    
No focal infiltrate .