FINDINGS:
Heart size is normal.  Hilar contours are unremarkable.  Focal pulled along
 the left lateral aspect of the descending thoracic aortic contour at the level
 of the aortic hiatus is noted.  The pulmonary vascularity is normal.  Focal
 round hazy opacity is noted within the left mid lung field, concerning for
 pneumonia.  Right lung is clear.  No pleural effusion or pneumothorax is
 identified.  There are no acute osseous abnormalities detected.

IMPRESSION:
1. Rounded hazy opacity in the left mid lung field, concerning for pneumonia.
 
 2. Left lateral bulge along the descending thoracic aortic contour at the
 level of the aortic hiatus, of uncertain etiology.  This could be further
 assessed with CT or MRI on a nonemergent basis.