Skip to navigation Skip to Content


Search Marshfield Clinic Health System
Join a world-class health system. Find jobs

Molecular Breast Imaging (MBI)

Molecular breast imaging (MBI) is used in addition to mammography. It can detect breast cancers as small as five millimeters. ​​

​​​​Molecular Breast Imaging (MBI) is just one of the early detection tests for breast cancer.

What is Molecular Breast Imaging (MBI)?

Molecular breast imaging (MBI) is used in addition to mammography. It can detect breast cancers as small as five millimeters. ​

MBI uses a radiotracer that "lights up" cancer tissue. There are clear differences between tumors and surrounding tissue.

​How is MBI different from a mammogram?

MBI is not a replacement for mammography. It should be used in addition to mammography.

Dense breast tissue may cause mammogram findings to be inconclusive. Cancers can appear white in mammograms, which is the same for dense breast tissue. As a result, dense breast tissue can sometimes mask tumors. Secondary screening may help rule out the presence of cancer.

Mammograms are best for screening imaging, while MBI lets your doctor see more clearly both healthy and diseased tissue.

​What does a MBI exam entail?

No advance preparation is required for a MBI exam.

You receive a low-dose injection of a short-lived radiotracer. The radiotracer "lights up" cancer tissue.

You sit comfortably in front of the MBI system. The breast is mildly compressed between two cameras. Generally, the MBI images are the same views taken during your mammogram. Then the images are compared.

The procedure takes 30 – 45 minutes. Images are immediately available for your doctor to review.

How do you prepare for a MBI exam?

A physician referral is necessary 
for all MBI exams. If you have a menstrual cycle, schedule your exam in days 1 – 10 of your cycle. (Day one is the first day of menstruation.)

Your MBI exam should be an additional exam to a mammogram, used to compare to the MBI exam.

For more information about MBI, talk with your doctor.​

When is MBI recommended?

You may benefit from MBI if you have a complex or dense breast tissue pattern.

Your physician may refer you for a MBI exam if you have an inconclusive finding on a mammogram or if you have dense breast tissue and also have one or more of the following factors:

  • You are at moderate or high risk for breast cancer.
  • You are unable to have a breast magnetic resonance imaging (MRI) exam because you have extreme claustrophobia, pacemaker, stent or other implant in your body.
  • Your mammogram, ultrasound or MRI image has abnormalities.
  • You have breast implants.
  • You have had breast cancer and need a scan to detect any signs of recurrence.
  • You are in chemotherapy and need to detect progress with your treatment.