IMPRESSION:
In comparison with the study of , there is increased
 opacification adjacent to the upper thoracic trachea with some retraction to
 the right.  This could reflect expansion of a mass or adenopathy or possibly
 even changes related to interval radiation therapy.  Increased opacification
 is seen at the right base. Although this could also represent postsurgical or
 treatment changes, in the appropriate clinical setting, superimposed pneumonia
 could be considered. Poor definition of the hemidiaphragm is consistent with
 atelectatic changes on the left as well.  If further imaging is warranted, CT
 would be the next procedure.