Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP and lateral radiographs of the chest demonstrate mild interval improvement in left upper lobe consolidation since the prior study , with better visualization of known left juxtahilar mass . The lung volumes are relatively low , but the left lower lobe and right lung are grossly clear . There is a small left pleural effusion , best appreciated on the lateral view . The heart size is top normal and is stable since the prior study .
    OUTPUT:
    
Mild interval improvement in left upper lobe post-obstructive pneumonia / atelectasis .