RAI Labs Duke

Digital Tomosynthesis Imaging of the Breast

Breast tomosynthesis (or "tomo" for short) is one of the most exciting research developments in radiology in recent years. We acquire x-ray images taken from many different angles, then use that data to reconstruct 3D images of the breast. Breast tomo lets radiologists detect and characterize suspicious lesions better, because it removes overlapping normal tissue which might otherwise obscure the lesions. The goal is to provide 3D information at the same high resolution and reasonable dose

Prototype breast tomosynthesis system

as mammography, while possibly reducing compression for improved patient comfort. Since the system will be based on digital mammography, it will also be faster and cheaper than alternatives requiring dedicated equipment such as CT or MR. For these reasons, breast tomo may be the first technique that can actually replace mammography in the near future, providing improved sensitivity and specificity of breast cancer diagnosis.

Many members of RAILabs contribute to this interdisciplinary team including Joseph Lo, Jim Dobbins, Ehsan Samei, and Carey Floyd. We are collaborating with Siemens Medical Solutions, a major industrial partner providing us with prototype hardware and invaluable scientific assistance.

The photo to the right shows the prototype breast tomo system with the x-ray tube at the end of its 50 degree scan arc (+25 degrees from middle position).

Below are some preliminary images from our on-going studies. This subject presented with a very subtle architectural distortion as shown in the standard mammogram (left). Even with the magnification view, the mass is still very subtle (middle). The tomo scan easily reveals a spiculated mass which was later biopsied to reveal invasive ductal carcinoma (right).
 

Mammogram shows very subtle architectural distortion (arrow).

Magnification view shows mass which is still very subtle (arrow).

Tomosynthesis slice image revealed obvious spiculated mass, biopsy revealed invasive cancer (arrow).

 

Another tomosynthesis case, movie loop shows different slices through the breast including a cancer.

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The best way to appreciate the 3D visualization of anatomy is to view the reconstructed slice images as a movie.

 

This is a different human subject, where another invasive cancer was barely visible in mammography because it was obscured by a scar from a previous benign biopsy. In tomo, the cancer is again readily visible as a spiculated mass in the center of slice 9-10. A close-up view of the mass is shown below too.

 

 

You can use the buttons to advance through the 3D slices one by one. At the beginning of the loop, you can see the skin pores that resemble leopard spots. Then as the slices enter the breast, you see normal anatomy such as vessels, ligaments, and glandular tissue. The cancer and biopsy scar then appear in the middle of the breast, followed by more normal tissue, and finally the skin pores as you exit the breast on the other side.