Digital Breast Tomosynthesis—Physics, Artifacts and Quality Control

Targeted CE per ARRT’s Discipline, Category, and Subcategory classification for enrollments starting after January 27, 2023:

Mammography: 2.25
Image Production: 2.25
Image Acquisition and Quality Assurance: 2.25

Outline

1. Introduction
2. Physical Principles of DBT
   1. Tube Motion
   2. Sweep Angle
   3. Number of Projections
   4. Radiation Dose
   5. Image Reconstruction
3. Artifacts
   1. Blurring-Ripple Artifacts
   2. Truncation Artifacts
   3. Loss of Skin and Superficial Tissue Resolution
   4. Motion Artifacts
   5. Additional DBT Artifacts
4. DBT QC
   1. Phantom Image Quality Testing
   2. Evaluation of Spatial Resolution
   3. Testing for Volume Coverage and Geometric Accuracy
   4. Flat-Field Testing
5. Conclusion

Objectives

Upon completion of this course, students will:

1. recognize when mammography gained widespread acceptance as a screening tool
2. identify advancements that were necessary for the commercialization of DBT
3. recall when the first DBT system was FDA cleared
4. understand how FFDM in combination with DBT compares to FFDM alone
5. learn a technique to minimize radiation dose when DBT is combined with FFDM
6. recall the percentage of mammography facilities in the U.S. offering DBT (in 2017)
7. recognize acquisition parameters shared by FFDM and DBT and those which are DBT-specific
8. understand what is meant by in-plane resolution and out-of-plane resolution
9. know how much depth information is contained in FFDM images, DBT images, and CT images
10. learn two different ways the x-ray tube may move during DBT
11. compare the sweep angles offered on different manufacturers’ DBT systems
12. recognize the benefit of a large vs. a small sweep angle
13. learn the relationship between number of projections, resolution, and radiation dose
14. remember the common materials used for the x-ray tube’s anode target and filter on DBT systems
15. know the MQSA radiation limit per mammography view
16. learn which direction on a DBT image has non-optimal resolution
17. identify the conventional tomographic reconstruction algorithm
18. identify an alternate tomographic reconstruction algorithm designed to improve image quality
19. study what a high-pass filter does during tomographic reconstruction
20. understand the orientation of reconstructed DBT images
21. learn a technique to delineate microcalcification distributions when using DBT
22. recall three artifacts specific to DBT
23. identify the reason for blurring-ripple artifacts
24. know the reconstruction algorithm used to make blurring-ripple artifacts least noticeable
25. explain the reason for truncation artifacts on DBT
26. identify how truncation artifacts appear on DBT
27. correlate a certain type of patient with loss of skin and superficial tissue resolution
28. list reasons for motion artifacts
29. know anatomical locations where motion artifacts are seen
30. know the necessary requirements before an imaging facility can perform DBT
31. describe the purpose of quality control on DBT systems
32. state how often a phantom image quality test should be performed and by whom
33. identify the type of phantom used to test spatial resolution
34. understand what a flat-field QC test is looking for
35. know who should perform the flat-field test and how often