The Radiotracer Tc-99m Sestamibi is injected Intravenously.   It concentrates in Cancerous Tissue due to increased vascularity and metabolic activity.

MBI procedure

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Molecular Breast Imaging (MBI) involves “Functional Imaging” providing information at a Molecular level. Mammography, Tomosynthesis and Ultrasound all provide Structural information.

Molecular changes in breast tissue precede Structural changes.  Molecular Imaging overcomes the problem of occult lesions hidden by Dense Breast parenchyma on Mammography

What is Molecular Breast Imaging?

Courtesy of GE Healthcare

Unlike Mammography, only gentle pressure is required for Immobilisation of the Breast between the two detectors. 

The patient may stand or sit comfortably while imaging is performed.

Two images are acquired for each breast for
​8-10 minutes in the CC and MLO positions to reproduce standard Mammographic views.

Radiation Dose:

The IV injection of a Radiotracer in MBI results in a different type of Radiation risk than Mammography.

The Radiation dose from MBI is relatively low at around annual background radiation levels.

MBI produces Whole Body Radiation vs Breast only Radiation in Mammography

The Effective Whole Body dose from 240MBq of Tc-99m Sestamibi is approximately 1.7 mSv.  This is higher than Mammography, but significantly lower than conventional Tc-99m Sestamibi Breast Imaging which required a higher injected dose.

The absorbed dose to Radiosensitive Breast Tissue from MBI is approximately 0.5 mGy (both Breasts).

This is significantly lower than Mammography.

The Radiotracer 99mTc-Sestamibi is excreted via the Hepatobiliary system and the kidneys.

The Radiation dose from MBI can be even further reduced with measures such as the addition of a fatty meal post injection of Radiotracer, the use of a laxative, hydration and frequent voiding.