Breast-Specific Gamma Imaging

Molecular Breast Imaging (MBI), also known as Breast-Specific Gamma Imaging (BSGI), is a nuclear medicine procedure that shows the metabolic activity of breast tissue. BSGI is less affected by variations in tissue density than traditional mammography and ultrasound, so it offers a valuable “second look” that can help determine whether a mass is likely to be benign or malignant. Also, in cases where mammography is inconclusive regarding the nature of lesions, BSGI is preferred, especially when patients present with:

  • Dense Breast Tissue

  • Palpable lesions not detected by mammography or ultrasound

  • Multiple suspicious lesions or clusters of calcifications

  • Pre-biopsy evaluations of suspect areas

  • Lobular carcinoma

  • Implants

  • Disease staging for breast conservation

  • Post-surgical or post-therapeutic breast

  • Difficult to interpret mammograms


The Procedure

A small amount of tracing agent is delivered via an IV, and is absorbed by all cells in the body. The tracing agent emits invisible gamma rays, which are detected by the camera and translated into a digital image of the breast. Due to the higher metabolic activity of cancerous cells, these cells absorb a greater amount of the tracing agent and are revealed as “dark spots.”

 Other tests, such as mammography and ultrasound, show only the physical structure of the breast. BSGI captures the actual cellular function of the breast tissue.


BSGI is not a replacement for yearly screening mammograms; it is used to aid in diagnosis when additional testing is indicated.



A board-certified radiologist will interpret the scan and send a report to your referring physician. Your referring physician will contact you with your results.