Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The degree of free air has probably decreased somewhat . There is similar elevation of the right hemidiaphragm . Left basilar opacity has improved substantially . There is persistent right middle lobe opacification , however , and basilar opacity in the right lower lobe , which is hard to compare to the prior frontal view . Small pleural effusions are also present .
    OUTPUT:
    
Probable decrease in free air since prior chest radiographs . Improved aeration at the left lung base . Similar appearance of right basilar opacities on frontal view , although difficult to compare to the prior study , which did not include a lateral view .