| Question 1: Which of the following image acquisition parameters in MRI are independent of image use; i.e. for Diagnosis or Radiation Therapy?
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| Reference: | Paulson, Eric S., et al. "Comprehensive MRI simulation methodology using a dedicated MRI scanner in radiation oncology for external beam radiation treatment planning." Medical physics 42.1 (2015): 28-39.
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| Choice A: | Slice thickness, spacing, and coverage. |
| Choice B: | Field-of-view (FOV). |
| Choice C: | Readout bandwidth (RBW). |
| Choice D: | Image acquisition time. |
| Choice E: | Image intensity non-uniformity. |
| Question 2: What characteristics of an MR Guided Radiotherapy system are most likely to impact spatial distortion?
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| Reference: | Baldwin L N, Wachowicz K, Thomas S D, Rivest R and Fallone B G 2007 Characterization, prediction, and correction of geometric distortion in 3T MR images Med. Phys. 34 388
Huang, Ke Colin, et al. "Phantom-based characterization of distortion on a magnetic resonance imaging simulator for radiation oncology." Physics in medicine and biology 61.2 (2016): 774.
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| Choice A: | Off-resonance induced distortions. |
| Choice B: | Susceptibility-induced distortions. |
| Choice C: | Gradient nonlinearity-induced distortion. |
| Choice D: | Axial radial distance from center of the bore. |
| Choice E: | Uniformity of the magnetic field. |
| Question 3: How might coil positioning relative to immobilization devices impact image quality and resultant dose distributions?
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| Reference: | Paulson, Eric S., et al. "Comprehensive MRI simulation methodology using a dedicated MRI scanner in radiation oncology for external beam radiation treatment planning." Medical physics 42.1 (2015): 28-39.
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| Choice A: | Coils placed directly on the patient, to increase signal intensity. |
| Choice B: | Coils placed near the patient with adjustable bridges to improve setup constancy. |
| Choice C: | Coils placed superior and inferior to the radiation beam. |
| Choice D: | Only the integrated body RF coil should be used to minimize patient surface dose. |
| Choice E: | Only intracavitary coils should be used in MR Guided Radiotherapy. |
| Question 4: How have commercial systems been designed to reduce the impact of externally generated RF on both the linear accelerator and the MRI?
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| Reference: | Shvartsman, Shmaryu M., et al. "Method and apparatus for shielding a linear accelerator and a magnetic resonance imaging device from each other." U.S. Patent No. 8,836,332. 16 Sep. 2014.
Raaymakers, B. W., et al. "Integrating a 1.5 T MRI scanner with a 6 MV accelerator: proof of concept." Physics in medicine and biology 54.12 (2009): N229.
Keall, Paul J., Michael Barton, and Stuart Crozier. "The Australian magnetic resonance imaging–linac program." Seminars in radiation oncology. Vol. 24. No. 3. WB Saunders, 2014.
Lamey, M., et al. "Radio frequency shielding for a linac-MRI system." Physics in medicine and biology 55.4 (2010): 995.
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| Choice A: | Sequence MR pulses and beam pulses out of phase from each other. |
| Choice B: | Place the magnet further away from the isocenter. |
| Choice C: | Place the linac further away from isocenter. |
| Choice D: | Surround the magnet with materials that can shield the RF of each system from the other. |
| Choice E: | Surround the linac with materials that can shield the RF of each system from the other. |
| Question 5: In which ways are the consequences of the Lorentz Force on the dose distribution being characterized and/or minimized?
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| Reference: | Reference: Raaijmakers, A. J. E., B. W. Raaymakers, and J. J. W. Lagendijk. "Integrating a MRI scanner with a 6 MV radiotherapy accelerator: dose increase at tissue–air interfaces in a lateral magnetic field due to returning electrons." Physics in medicine and biology 50.7 (2005): 1363.
Raaijmakers, A. J. E., B. W. Raaymakers, and J. J. W. Lagendijk. "Experimental verification of magnetic field dose effects for the MRI-accelerator." Physics in medicine and biology 52.14 (2007): 4283.
Raaijmakers, A. J. E., B. W. Raaymakers, and J. J. W. Lagendijk. "Magnetic-field-induced dose effects in MR-guided radiotherapy systems: dependence on the magnetic field strength." Physics in medicine and biology 53.4 (2008): 909.
Kirkby, C., et al. "Patient dosimetry for hybrid MRI‐radiotherapy systems." Medical physics 35.3 (2008): 1019-1027.
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| Choice A: | Increasing the strength of the magnetic field. |
| Choice B: | Decrease the kinetic energy of the electrons. |
| Choice C: | Apply an opposed magnetic field. |
| Choice D: | Measurements with film in unit density phantoms with air cavities. |
| Choice E: | Measures with a Farmer chamber in phantom. |
| Question 6: What unique quality assurance systems are not commercially available to perform dose measurements in the presence of a magnetic field?
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| Reference: | Reynolds, Michael Watson. Dose Response of Selected Radiation Detectors in a Magnetic Field. Diss. University of Alberta, 2015.
Wooten, H. Omar, et al. "Benchmark IMRT evaluation of a Co-60 MRI-guided radiation therapy system." Radiotherapy and Oncology 114.3 (2015): 402-405.
Park, Jong Min, et al. "Commissioning experience of tri-cobalt-60 MRI-guided radiation therapy system." Progress in Medical Physics 26.4 (2015): 193-200.
Ellefson, Steven T., et al. "An analysis of the ArcCHECK‐MR diode array's performance for ViewRay quality assurance." Journal of Applied Clinical Medical Physics (2017).
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| Choice A: | Percent depth dose values for various beam angles. |
| Choice B: | Patient specific delivery quality assurance devices for IMRT QA. |
| Choice C: | Dose profile measurements to assess beam flatness and symmetry. |
| Choice D: | Radiation dose output measurements. |
| Choice E: | Radiation doses on the patient’s skin surface. |
| Question 7: In which order of anatomical sites, listed below, has realtime MRI Guided radiotherapy provided the greatest benefit:
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| Reference: | Chen, I., et al. "Quantification of Interfractional Gastrointestinal Tract Motion for Pancreatic Cancer Radiation Therapy." International Journal of Radiation Oncology• Biology• Physics 96.2 (2016): E144.
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| Choice A: | Lung, Abdomen, Breast, Pelvis. |
| Choice B: | Abdomen, Lung, Pelvis, Breast. |
| Choice C: | Pelvis, Lung, Breast, Abdomen. |
| Choice D: | Breast, Abdomen, Lung, Pelvis. |
| Choice E: | Lung, Abdomen, Pelvis, Breast. |
| Question 8: List the techniques that have been used to improve tumor visualization, from those with the shortest to longest sustainable temporal effect?
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| Reference: | Wojcieszynski, Andrzej P., et al. "Gadoxetate for direct tumor therapy and tracking with real-time MRI-guided stereotactic body radiation therapy of the liver." Radiotherapy and Oncology 118.2 (2016): 416-418.
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| Choice A: | Drinking a glass of water, intravenous liver contrast, rectal gel. |
| Choice B: | Drinking a glass of water, rectal gel, intravenous liver contrast. |
| Choice C: | Intravenous liver contrast, rectal gel, drinking a glass of water. |
| Choice D: | Intravenous liver contrast, drinking a glass of water,rectal gel. |
| Choice E: | Rectal gel, drinking a glass of water, intravenous liver contrast. |
| Question 9: What are the most common indications for on-line adaptive radiotherapy observed in clinical practice?
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| Reference: | Kashani, R., et al. "Commissioning and Clinical Implementation of the First Online Adaptive MR Image Guided Radiation Therapy Program." International Journal of Radiation Oncology• Biology• Physics 93.3 (2015): S18-S19.
Henke, L. E., et al. "Online Adaptive Magnetic Resonance–Guided (OAMR)-Stereotactic Body Radiation Therapy for Abdominal Malignancies: Prospective Dosimetric Results from a Phase 1 Trial." International Journal of Radiation Oncology• Biology• Physics 96.2 (2016): S222-S223.
Mittauer, K., et al. "TU‐AB‐BRA‐11: Indications for Online Adaptive Radiotherapy Based On Dosimetric Consequences of Interfractional Pancreas‐To‐Duodenum Motion in MRI‐Guided Pancreatic Radiotherapy." Medical physics 43.6 (2016): 3735-3736.
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| Choice A: | Patient rotation of daily setup alignment. |
| Choice B: | Geometric uncertainty in deformation algorithm. |
| Choice C: | OAR exceeds dose and/or target undercoverage. |
| Choice D: | OAR or target changes in respiratory motion. |
| Choice E: | Patient weight loss. |
| Question 10: What unique strategies are being used to increase the duty cycle and targeting accuracy for MRI Guided motion management?
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| Reference: | Rosenberg, S. A., et al. "Real-Time Magnetic Resonance Imaging Guided Radiation Therapy for Gastroesophageal Junction/Gastric Cancers." International Journal of Radiation Oncology• Biology• Physics 96.2 (2016): S61.
Wojcieszynski, Andrzej P., et al. "Dosimetric Comparison of Real-Time MRI-Guided Tri-Cobalt-60 Versus Linear Accelerator-Based Stereotactic Body Radiation Therapy Lung Cancer Plans." Technology in cancer research & treatment 16.3 (2017): 366-372.
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| Choice A: | Visual display seen by the patient in real time. |
| Choice B: | Meditation training to improve stability of respiratory pattern. |
| Choice C: | Medication to normalize respiration. |
| Choice D: | MRI compatible ventilators to program breathing amplitude and frequency. |
| Choice E: | Patient self-directed / RTT assisted breath hold. |
