Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . Mediastinal and hilar contours are unremarkable . There is no pulmonary edema . Minimal atelectasis is seen in the lung bases . No focal consolidation , pleural effusion or pneumothorax is identified . There are no acute osseous abnormalities . Degenerative changes of the right acromioclavicular joint are noted with a well corticated ossific density superior to the joint seen .
    OUTPUT:
    
Mild bibasilar atelectasis .