IMPRESSION:
Endotracheal tube continues to have its tip approximately 4.5 cm above the
 carina.  The left internal jugular central line terminates in the proximal
 SVC.  A nasogastric tube is seen coursing below the diaphragm with the tip not
 identified.  There continues to be a diffuse interstitial abnormality with
 some superimposed patchy opacities at both bases.  There is relative sparing
 in the right upper lobe.  Overall, the imaging appearance is not significantly
 changed dating back to .  However, in the absence of more remote
 imaging, it is difficult to determine whether this represents pre-existing
 chronic interstitial lung disease and/or emphysematous changes or whether this
 is a more acute process superimposed on a chronic interstitial lung disease. 
 Clinical correlation is therefore advised and comparison to outside imaging
 would be extremely helpful.  Overall cardiac and mediastinal contours are
 stable.  No pneumothorax.