| Question 1: What is the relationship between tumor motion measurement relative errors and commercial low-pitch helical motion? |
| Reference: | T. Dou, D. Thomas, D. O’Connell, J. Bradley, J. Lamb, and D.A. Low, Technical Note: Simulation of 4DCT tumor motion measurement errors, Med. Phys. 42, 6084-6089 (2015). |
| Choice A: | No relationship |
| Choice B: | Related only to breathing amplitude |
| Choice C: | Worse with higher CT pitch |
| Choice D: | Significant only for regularly breathing patients |
| Question 2: What is the reason that fast-helical CT techniques for model-based CT are more robust to irregular breathing than commercial low-pitch techniques? |
| Reference: | D. O’Connell, D. Ruan, D. Thomas, T. Dou, J. Lewis, A. Santhanam, P. Lee, and D.A. Low, A prospective gating method to acquire a diverse set of free-breathing CT images for model-based 4DCT, Accepted for publication, Physics in Medicine and Biology, January 2018. |
| Choice A: | Not true. |
| Choice B: | Fast-helical CT is faster than the low-pitch helical CT. |
| Choice C: | Fast-helical CT gives far greater dose than low-pitch CT. |
| Choice D: | Fast helical CT samples breathing over a longer period of time than low-pitch CT. |
| Question 3: Which one of the following is incorrect in terms of scan duration per step in cine 4DCT? |
| Reference: | Pan T, Lee TY, Rietzel E and Chen GTY. 4D-CT imaging of a volume influenced by respiratory motion on multi-slice CT. Med. Phys 31(2):333-340, 2004. |
| Choice A: | One breath cycle. |
| Choice B: | One breath cycle plus 1 sec. |
| Choice C: | One and a half breath cycles. |
| Choice D: | Two breath cycles. |
| Question 4: What will happen if the helical 4DCT was stopped manually by the operator? |
| Reference: | Pan T, Martin RM, Luo D. New prospective 4D-CT for mitigating the effects of irregular respiratory motion. Physics in Medicine & Biology 62(15):N350-N361, 7/2017 |
| Choice A: | The scan can be resumed and the scan will continue from where it was stopped. |
| Choice B: | The scan is finished and it cannot be resumed at the location where it was stopped. |
| Choice C: | A system password is needed to resume the scan. |
| Choice D: | The scan will automatically resume after one more breath cycle. |
| Question 5: What will happen if the cine 4DCT was stopped manually by the operator? |
| Reference: | Pan T, Martin RM, Luo D. New prospective 4D-CT for mitigating the effects of irregular respiratory motion. Physics in Medicine & Biology 62(15):N350-N361, 7/2017 |
| Choice A: | The scan can be resumed and the scan will continue from where it was stopped. |
| Choice B: | The scan is finished and it cannot be resumed at the location where it was stopped. |
| Choice C: | A system password is needed to resume the scan. |
| Choice D: | The scan will automatically resume after one more breath cycle. |
| Question 6: Which of the following steps is incorrect in processing the prospective 4DCT data? |
| Reference: | Pan T, Martin RM, Luo D. New prospective 4D-CT for mitigating the effects of irregular respiratory motion. Physics in Medicine & Biology 62(15):N350-N361, 7/2017 |
| Choice A: | A retrospective reconstruction is needed to remove the redundant 4DCT data. |
| Choice B: | There is no need for offline data processing. |
| Choice C: | All data processing can be done on the console. |
| Choice D: | Patient respiratory signal needs to be re-processed. |
