| Question 1: Which of the following dual-energy technique provides the worst spectral separation for the low and high energy images? |
| Reference: | Schmitzberger, F. F., et al. (2011). Development of Low-Dose Photon-counting Contrast-enhanced Tomosynthesis with Spectral Imaging. Radiology: 558-564 |
| Choice A: | Two separate exposures, 28 kVp W/Al for low energy, 49 kVp W/Cu for high energy |
| Choice B: | Photon counting detector with two energy bins, 45 kVp with W/Al |
| Choice C: | Dual layer detector (200 micron selenium + 200 micron selenium), 45 kVp with W/Al |
| Question 2: Which of the following statement is true regarding flat panel detectors when 28 kVp W/Al is used as low energy (LE) and 49 kVp W/Cu used as high energy (HE) spectra |
| Reference: | Rowlands, J. A. and J. Yorkston (2000). Flat panel detectors for digital radiography. Medical Imaging: Volume 1 Physics and Psychophysics, Psychophysics. H. K. a. R. V. M. J Beutel. Bellingham, SPIE: 223-328 |
| Choice A: | With the same 200 micron thickness, CsI indirect detector has higher quantum efficiency (QE) than direct selenium detector for LE |
| Choice B: | With the same 200 micron thickness, CsI indirect detector has higher QE than direct selenium detector for HE |
| Choice C: | CsI indirect detector has higher spatial resolution than direct selenium detector when pixel size is 100 microns |
| Question 3: Cone-beam CT systems with multi-source configurations arranged as an array of sources parallel to the rotation axis can help in alleviating effects associated to incomplete sampling, such as: |
| Reference: | A. E. Becker, A. M. Hernandez, P. R. Schwoebel, J. M. Boone (2020). Cone beam CT multisource configurations: evaluating image quality, scatter, and dose using phantom imaging and Monte Carlo simulations. Physics in Medicine and Biology 65, 235032 |
| Choice A: | Artifacts associated to beam hardening effects |
| Choice B: | Shading and loss of resolution at slices far from the central slice, commonly known as cone-beam effects |
| Choice C: | Artifacts associated to sparse angular sampling |
| Question 4: One of the benefits of multi-source array configurations for digital breast tomosynthesis is the removal of need for mechanical motion of the x-ray source during tomosynthesis image acquisition, resulting in shorter scan times. Long scan times are associated with |
| Reference: | N. Tirada, G. Li, D. Dreizin, L. Robinson, G. Khorjekar, S. Dromi, T. Ernst (2019). Digital Breast Tomosynthesis: Physics, Artifacts, and Quality Control Considerations. Radiographics 39(2), 413-426 |
| Choice A: | Larger radiation dose |
| Choice B: | Increased image noise |
| Choice C: | Image blur and artifacts from patient motion |
| Question 5: Distributed x-ray source technologies include approaches based on “hot cathode” designs, based on thermionic electron emission, and approaches based on “cold cathode” designs, based on field emission technology. Sources based carbon nanotube (CNT) technology are an example of: |
| Reference: | V. B. Neculaes, P. M. Edic, M. Frontera, A. Caiafa, G. Wang, B. De Man (2014). Multisource X-Ray and CT: Lessons Learned and Future Outlook. IEEE Access, vol. 2, pp. 1568-1585, 2014, doi: 10.1109/ACCESS.2014.2363949 |
| Choice A: | Hot cathode x-ray sources |
| Choice B: | Cold cathode x-ray sources |
| Question 6: What are the historically considered main concern(s) with field emission sources that have hampered their application until recently? |
| Reference: | B. Gonzales, D. Spronk, Y. Cheng, A. W. Tucker, M. Beckman, O. Zhou, J. LU (2014). Rectangular Fixed-Gantry CT Prototype: Combining CNT X-Ray Sources and Accelerated Compressed Sensing-Based Reconstruction. IEEE Access, vol. 2, pp. 971-981, 2014, doi: 10.1109/ACCESS.2014.2351751 |
| Choice A: | High cost |
| Choice B: | Tube lifetime and maximum power |
| Choice C: | Capability to be arranged in array configurations |
| Question 7: The accuracy or suitability of mammography for screening is often limited for women: |
| Reference: | International Agency for Research on Cancer. IARC Handbooks of Cancer Prevention, Volum 15 Breast Cancer Screening [Internet]: International Agency for Research on Cancer, 2016. Available: http://publications.iarc.fr/Book-And-Report-Series/Iarc-Handbooks-Of-Cancer-Prevention/Breast-Cancer-Screening-2016
Nelson HD, O'Meara ES, Kerlikowske K, et al. Factors associated with rates of false-positive and false-negative results from digital mammography screening: an analysis of registry data. Ann Intern Med 2016; 164:226–35.doi:10.7326/M15-0971
Alonzo-Proulx O, Mainprize JG, Harvey JA, Yaffe MJ. Investigating the feasibility of stratified breast cancer screening using a masking risk predictor. Breast Cancer Res. 2019 Aug 9;21(1):91
Yaffe MJ, Jong RA, Pritchard KI. Breast Cancer Screening: Beyond Mortality. Journal of Breast Imaging, Volume 1, Issue 3, September 2019, Pages 161–165. |
| Choice A: | Who are at high risk due to certain mutations |
| Choice B: | Under the age of 40 |
| Choice C: | With complex, dense patterns of fibroglandular tissue |
| Choice D: | All of the above |
| Question 8: A potential advantage of “liquid biopsy” is that it |
| Reference: | Croessmann S, Park BH. Circulating tumor DNA in early-stage breast cancer: new directions and potential clinical applications. Clin Adv Hematol Oncol. 2021 Mar;19(3):155-161. PMID: 33739964.
Crosby, D. Delivering on the promise of early detection with liquid biopsies. Br J Cancer 126, 313–315 (2022). https://doi.org/10.1038/s41416-021-01646-w. |
| Choice A: | Is a well-established method for detecting breast cancer |
| Choice B: | Provides exquisite spatial localization |
| Choice C: | May allow earlier detection and could identify multiple cancers at the same time |
| Question 9: Which of the following is true regarding screening mammograms? |
| Reference: | Monticciolo DL, Newell MS, Hendrick RE, Helvie MA, Moy L, Monsees B, Kopans DB, Eby PR, Sickles EA. Breast Cancer Screening for Average-Risk Women: Recommendations From the ACR Commission on Breast Imaging. J Am Coll Radiol. 2017 Sep;14(9):1137-1143. doi: 10.1016/j.jacr.2017.06.001. Epub 2017 Jun 22. PMID: 28648873.
Tabár L, Dean PB, Chen TH, Yen AM, Chen SL, Fann JC, Chiu SY, Ku MM, Wu WY, Hsu CY, Chen YC, Beckmann K, Smith RA, Duffy SW. The incidence of fatal breast cancer measures the increased effectiveness of therapy in women participating in mammography screening. Cancer. 2019 Feb 15;125(4):515-523. doi: 10.1002/cncr.31840. Epub 2018 Nov 8. PMID: 30411328; PMCID: PMC6588008 |
| Choice A: | Sensitivity of digital mammography is unaffected by breast density. |
| Choice B: | Screening detected cancers have poorer prognosis than clinically detected ones |
| Choice C: | Women who have participated in mammography screening have greater benefit from the therapy available at the time of diagnosis than do those who have not participated |
| Choice D: | Screening mammography only benefits women over 50 years of age |
| Question 10: An advantage of DBT over DM in screening is |
| Reference: | Skaane, P., et al. Comparison of digital mammography alone and digital mammography plus tomosynthesis in a population-based screening program. Radiology 267, 47-56 (2013).
Ciatto, S., et al. Integration of 3D digital mammography with tomosynthesis for population breast-cancer screening (STORM): a prospective comparison study. Lancet Oncol 14, 583-589 (2013). |
| Choice A: | Decreased architectural distortion detection |
| Choice B: | Improved calcification detection |
| Choice C: | Increased recall rates |
| Choice D: | Increase in cancer detection |
