Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Endotracheal tube tip terminates approximately 5 .3 cm from the carina . Mild enlargement of the cardiac silhouette is present . Aortic knob calcifications are visualized . Lung volumes are low with widening of the superior mediastinal contour which may be due to low lung volumes and supine AP technique . Pulmonary vasculature is not engorged . Airspace opacification in the left lung base is concerning for atelectasis or infection along with a small left pleural effusion . No large pneumothorax is present . There are no acute osseous abnormalities visualized .
    OUTPUT:
    
1 . Standard positioning of the endotracheal tube . 2 . Left basilar opacification may reflect atelectasis or infection along with a small left pleural effusion . 3 . Widening of the superior mediastinal contour is likely due to a combination of low lung volumes , supine positioning and AP technique . If there is concern for vascular abnormality , CT of the chest is recommended for further assessment .