Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lines and tubes : ET tube tip is approximately 3 cm above the carina . Right IJ venous line tip is approximately at the CA junction . NG tube passes into the stomach and the tip is not imaged , but the side port is at least 5 cm below the GE junction . Heart size is normal . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . Substantial left lower lobe atelectasis persists . No pleural effusion or pneumothorax . The tip of an IVC filter is seen in the upper abdomen , but can not be localized on this view alone
    OUTPUT:
    
Persistent severe left lower lobe atelectasis .