Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There has been interval placement of an endotracheal tube with the tip terminating 4 .5 cm above the carina . There is interval decreased dilatation of the trachea from the most recent prior radiograph . The lung volumes remain low with increased opacification at the left lung base greater than the right which may represent substantial atelectasis but potentially pneumonia in the appropriate setting . The lung volumes are increased with somewhat better aeratation especially at the left lung base . Tortuosity and calcification of the thoracic aorta is re-demonstrated . The cardiac silhouette is incompletely evaluated . Surgical clips in the right upper quadrant of the abdomen are compatible with prior cholecystectomy . Surgical clips are also noted at the left hemidiaphragm and in the left upper quadrant of the abdomen .
    OUTPUT:
    
1 . Endotracheal tube with tip 4 .5 cm above the carina . 2 . Somewhat better aeration but persistent focal left basilar retrocardiac opacity .