Ductography (or galactography) is a contrast enhanced form of mammography that evaluates the source of spontaneous nipple discharge occurring from a single duct in one breast. This exam is most often beneficial in women with clear or bloody nipple discharge and a normal mammogram and ultrasound. It is generally not indicated in women with discharge from multiple ducts or for discharge that is milky, yellow, green or gray in color. The most common cause of nipple discharge is a papilloma, which is a noncancerous growth within a duct. Cancer such as ductal carcinoma in situ (DCIS) is an uncommon cause of clear or bloody nipple discharge.
To perform a ductogram, the doctor or patient must be able to express the discharge from the breast so that the correct duct can be examined. After the nipple is cleansed, a thin catheter is inserted into the duct, and a small amount of contrast dye is injected. The contrast opacifies the internal contour of the duct. The patient may feel pressure or fullness in the breast when the dye is injected. Several mammographic images are obtained, and the images are evaluated for masses or areas of narrowing/irregularity within the duct. If there is an abnormality, this section of the milk duct may then be surgically removed. The main contraindication to ductography is an allergy to iodinated contrast medium.