Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared one day earlier and allowing for differences in technique , there has been possible slight interval improvement at the right and left lung bases , with suggestion of increased lucency at both lung bases . Otherwise , I doubt significant interval change . Note is made of a tapered , well corticated appearance to the right distal clavicle --___ there history of prior surgery to account for this ?
    OUTPUT:
    
As above . .