Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Tracheostomy ends 3 .4 cm above carina . Right subclavian line is in lower SVC . Left lower lung collapse has improved a lot . Right moderate pleural effusion with mild atelectasis is unchanged . The mediastinal contours are within normal limits .
    OUTPUT:
    
Improvement of left lower lobe atelectasis . The rest of the exam is unchanged .