Honestly, neither of us have ever seen a ductogram. They can be performed under mammography or MRI and involve the injection of contrast material through a small catheter placed directly into the nipple.
The purpose is to visualize the ducts within the breast and identify blockages.
You may be recommended to undergo this type of diagnostic work up if you unexplained or bloody nipple discharge with no other imaging abnormality.
We are finding that patients more frequently get taken directly to the OR for nipple exploration as may ductograms find things that would need to be removed surgically anyway.
Check Radiopaedia's explanation of the procedure for more detailed information by clicking HERE.
Or listen to Dr. Tashian's explanation from RadiologyInfo.org: