These are CAT scan images showing lung nodules. They are the small round white circles along the outer edge of my lungs. After a needle lung tissue biopsy and labs, it was determined they were caused by some sort of infection and were not cancer or Rheumatoid nodules. It's important to know that throughout the whole ordeal my lungs sounded clear when I was examined. If you feel pain when you breathe or are short of breath, do yourself a favor and get it checked out.