Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Postoperative appearance of cardiomediastinal contours is stable since ___ . Bibasilar atelectasis has substantially improved in the interval , and bilateral pleural effusions have decreased in size with residual small effusions remaining , left greater than right . Tiny right apical pneumothorax is in retrospect decreased in size since ___ .
    OUTPUT:
    
Substantial improvement in bibasilar atelectasis and slight decrease in bilateral pleural effusions .