FINDINGS:
The cardiomediastinal silhouettes are stable, reflective of mild cardiomegaly.
 The left hilum is within normal limits.  The right hilum is obscured.  There
 is complete or near complete atelectasis/collapse of the right upper lobe with
 associated convex bulging medially (reverse S sign of Golden).  The remaining
 right lung appears well-aerated without focal consolidation.  The left lung is
 clear.  There is no pulmonary vascular congestion or pulmonary edema.  There
 is no pneumothorax or pleural effusion.  Anterior spinal fusion hardware is
 noted.  Cholecystectomy clips overlie the right upper abdominal quadrant.

IMPRESSION:
1. Complete collapse of the right upper lobe with central convex border,
 highly suggestive of an obstructing central mass such as lung cancer. 
 Recommend CT chest for further evaluation.
 2. Stable mild cardiomegaly.
 
 RECOMMENDATION(S):  Recommend CT chest for further characterization of right
 upper lobe collapse.