Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to the prior study , there is slightly improved aeration of the right lower lobe with persistent collapse of the right middle lobe and atelectasis of the right lower lobe . The left lung is clear . The mediastinum remains shifted to the right . No pneumothorax . Tracheostomy tube and right PICC are in unchanged satisfactory position .
    OUTPUT:
    
Somewhat improved aeration of the right lower lobe with persistent right middle lobe collapse and right lower lobe atelectasis .