IMPRESSION:
1.  Overall cardiac and mediastinal contours are stable.  There continues to
 be a diffuse bilateral predominantly interstitial abnormality in the lungs
 with more focal vague opacity in the left upper peripheral lung.  When
 compared to the most recent prior study, there is no significant interval
 change, although these findings are more pronounced when compared to studies
 from .  Therefore, these findings favor persistent interstitial edema
 rather than an infectious process.  Clinical correlation would be advised. 
 There is a small layering left effusion.  There is overall improved aeration
 at the right base when compared to more remote studies.  Heart remains
 enlarged.  Calcification of the aorta consistent with atherosclerosis.  No
 pneumothorax.