How CAD can help save time in mammography reading


In mammography screening, the workload for radiologists is extremely high – and continues to grow. With digital breast tomosynthesis, the data volume will increase even further and, consequently, the reading time. But there are smart tools available that support radiologists in saving on reading time.

There are already various tools widely in use that support radiologists in decreasing the evaluation time:

  • Slabbing reduces the amount of images to be viewed, as e.g. 1 mm slices are joined to form thicker slices.
  • Correlation links define the area where it’s possible to find the lesion when switching between several projections of 2D and 3D images.
  • O’clock positioning helps the reader automatically and reproducibly define the exact lesion position.
  • Automated measurement tools help define the location of a lesion by immediately displaying the distance to the skin line, nipple, and chest wall.

Since being introduced to the market in the late 1990s, the CAD algorithms for mammography have been constantly evolving. The first algorithms used to detect conspicuous tissue in 2D mammograms were laboriously programmed – and not highly reliable. Nowadays, CAD systems utilize image analysis and deep learning technologies1). Information from thousands of mammography images are incorporated into the algorithms, enabling the product to distinguish between characteristics of cancerous and normal tissue.2) These CAD systems clearly identify lesion candidates in both 2D mammograms and 3D tomosynthesis volumes.

There are various studies available that take a closer look at the efficacy of CAD. Adding CAD to single reading usually shows an increase in sensitivity and/or cancer detection rate, while there’s no significant difference when comparing double reading with single reading plus CAD. Many studies also report an increase in recall rate when adding CAD.3)