FINDINGS:
Cardiac silhouette size is normal.  A descending thoracic aortic stent graft
 is noted.  Mediastinal hilar contours are otherwise unremarkable.  Pulmonary
 vasculature is not engorged.  Low lung volumes are present with mild bibasilar
 patchy opacities, likely atelectasis.  No pleural effusion or pneumothorax is
 present.  There are no acute osseous abnormalities.

IMPRESSION:
Low lung volumes with probable mild bibasilar atelectasis.