| Question 1: Within the context of current technology, the fourth dimension of 4D-MRI refers to: |
| Reference: | Reference: Stemkens B, Paulson ES, Tijssen RHN. Nuts and bolts of 4D-MRI for radiotherapy. Phys Med Biol. 2018 Oct 23;63(21):21TR01. doi: 10.1088/1361-6560/aae56d |
| Choice A: | Time |
| Choice B: | Respiratory phase |
| Choice C: | Fraction number |
| Choice D: | None of the above |
| Question 2: Advantages of 3D acquisition strategies over 2D acquisition strategies for generation of 4D-MRI include: |
| Reference: | Stemkens B, Paulson ES, Tijssen RHN. Nuts and bolts of 4D-MRI for radiotherapy. Phys Med Biol. 2018 Oct 23;63(21):21TR01. doi: 10.1088/1361-6560/aae56d. |
| Choice A: | Increased signal-to-noise ratio (SNR) |
| Choice B: | Contrast flexibility |
| Choice C: | Reconstruction speed |
| Choice D: | Image orientation flexibility |
| Choice E: | None of the above |
| Question 3: Challenges with use of external surrogates for retrospective re-binning in 4D-MRI include: |
| Reference: | Stemkens B, Paulson ES, Tijssen RHN. Nuts and bolts of 4D-MRI for radiotherapy. Phys Med Biol. 2018 Oct 23;63(21):21TR01. doi: 10.1088/1361-6560/aae56d. |
| Choice A: | Signal saturation |
| Choice B: | Gain resetting |
| Choice C: | Synchronization of start and end times with pulse sequence acquisition |
| Choice D: | Loss of phase coherence with acquired k-space data |
| Choice E: | All of the above |
| Question 4: Which of the following motions is best characterized by cine MRI? |
| Reference: | Paulson ES, Tijssen RHN. “Motion Management.” MRI for Radiotherapy, edited by Liney G and van der Heide UA, Springer, 2019, 107-116. |
| Choice A: | Slow, ultracyclic motion |
| Choice B: | Periodic motion |
| Choice C: | Fast, aperiodic motion |
| Choice D: | All of the above |
| Choice E: | None of the above |
| Question 5: What is the main advantage of the MR-only workflow for RT plan simulation? |
| Reference: | K. Brock and L. Dawson. Point: Principles of Magnetic Resonance Imaging Integration in a Computed Tomography-based Radiotherapy Workflow |
| Choice A: | Improved special resolution and accuracy |
| Choice B: | Less radiation dose delivered to the patient |
| Choice C: | Simplified workflow due to less contouring |
| Choice D: | Consistent target and OARs delineation and reduced image processing errors |
| Question 6: Which statement is correct with regard to MR-only and synthetic CT based simulation |
| Reference: | J. Edmund and T. Nyholm. Counterpoint: A Review of Substitute CT Generation for MRI-only Radiation Therapy. Rad Oncol 12:28, 2017 |
| Choice A: | Synthetic CT requires a CT in addition to MR data |
| Choice B: | MR-only workflows do not require any CT-related prior information |
| Choice C: | Synthetic CT is used for both soft-tissue contouring and dose computations |
| Choice D: | Synthetic CT is a desirable addition to the MR-only workflow to facilitate accurate dose computations |
| Question 7: Which of the following does NOT represent a method for facilitating the assignation of Hounsfield Units to MR data? |
| Reference: | T. Nyholm and J. Jonsson. Opportunities and Challenges of a Magnetic Resonance Imaging–Only Radiotherapy Work Flow. Sem Rad Onc 175-180, 2014. |
| Choice A: | Atlas-based segmentation |
| Choice B: | Simulated annealing |
| Choice C: | Manual contouring |
| Choice D: | Voxelwise conversion |
| Question 8: Physician requested in the simulation order a field of view from the hip down to the knee for a large soft tissue sarcoma lesion. What is the best way to achieve the necessary field of view? |
| Reference: | Paulson ES, Erickson B, Schultz C, Li XA. Comprehensive MRI simulation methodology using a dedicated MRI scanner in radiation oncology for external beam radiation treatment planning. Medical Physics. 2015;42(1):28-39. |
| Choice A: | Increase slice thickness and in-plane pixel size to scan within reasonable time frame |
| Choice B: | Angulate your planning scan volume for higher efficiency |
| Choice C: | Step-and-shoot or continuous moving table acquisition |
| Choice D: | Increase readout bandwidth |
| Question 9: For a prostate cancer patient with hip implants, which of the following strategies would aid with reducing metallic imaging artifacts? |
| Reference: | Hargreaves BA, Worters PW, Pauly KB, Pauly JM, Koch KM, Gold GE. Metal-induced artifacts in MRI. AJR Am J Roentgenol. 2011;197(3):547-555.
Lu W, Pauly KB, Gold GE, Pauly JM, Hargreaves BA. SEMAC: Slice Encoding for Metal Artifact Correction in MRI. Magnetic Resonance in Medicine. 2009;62(1):66-76 |
| Choice A: | Slice-encoding metal artifact correction (SEMAC) |
| Choice B: | Use spin-echo based pulse sequence over GRE sequences |
| Choice C: | View angle tilting (VAT) |
| Choice D: | Increase receiver and excitation bandwidth |
| Choice E: | All of the above |
| Question 10: Which of the following descriptions about MRI respiratory management methods are incorrect? |
| Reference: | Glide-Hurst C, Paulson E, McGee K, Tyagi N, Hu Y, Balter J, Bayouth J. AAPM Task Group 284 Report: Magnetic Resonance Imaging Simulation in Radiotherapy: Considerations for Clinical Implementation, Optimization, and Quality Assurance. Medical Physics 2021 |
| Choice A: | Breath-hold imaging typically uses fast spin-echo sequences with parallel imaging and reduced phase resolution times |
| Choice B: | Respiratory triggered acquisitions can be performed with internal MR navigators |
| Choice C: | Desired respiratory phases can be acquired when the trigger level and trigger delay are optimized |
| Choice D: | Cartesian sampling of k-space is more motion sensitive than Radial k-space sampling |
