2016 AAPM Annual Meeting
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Session Title: AAPM-AMPR (Russia)-SEFM (Spain) Joint Course on Challenges and Advantages of Small Field Radiation Treatment Techniques
Question 1: The condition of lateral charged particle non-equilibrium in small photon fields....
Reference:Aspradakis, M.M. et al, (2010), IPEM Report 103: Small field dosimetry
Choice A:Only manifests itself when attempting to measure absorbed dose to water using an air-filled chamber in small fields.
Choice B:Is a condition that reduces absorbed dose on the central axis of small fields.
Choice C:Affects the stopping power ratio water to air in small fields.
Choice D:Is present, regardless of whether a detector is used in the field.
Choice E:Makes measurements of beam output with air-filled ionization chambers in small fields possible.
Question 2: Unshielded diode detectors show field size-dependent correction factors due to two competing effects:
Reference:Francescon, P., et al (2011), Med Phys 38:6513; Benmakhlouf, H., et al (2014), Med Phys 41:041711
Choice A:Intrinsic energy dependence of Si and volume averaging.
Choice B:Intrinsic energy dependence of Si and perturbation effects.
Choice C:Polarity effect and recombination.
Choice D:Polarity effect and electrometer calibration.
Choice E:Recombination effect and diode doping.
Question 3: Indicate the single set of two largest contributors to correction factors and their uncertainties for commercial air-filled ionization chambers in small photon fields...
Reference:Crop et al (2009) Phys Med Biol 54(9). p.2951-2969; Bouchard et al (2009) Med Phys 36 (10), 4654-4663
Choice A:The stopping power ratio and the central electrode effect.
Choice B:The stopping power ratio and the chamber wall effect.
Choice C:The fluence perturbation effect and the volume averaging effect.
Choice D:The stopping power ratio and the volume averaging effect.
Choice E:The ionization chamber wall effect and the stem effect.
Question 4: Beam quality specification and the measurement of the beam quality specifier in the IAEA-AAPM small-field dosimetry protocol is required for the following reasons:
Reference:Palmans, H., (2012) Med Phys 39: 5513-9
Choice A:To specify the correction factors to be applied to the measured output ratios.
Choice B:To specify small field output factors.
Choice C:To specify the kQmsr,Qref beam quality correction factor in the msr field.
Choice D:To ensure the beam is of adequate quality.
Choice E:To specify the absorbed dose calibration coefficient for a small field.
Question 5: What is the most common workflow step where errors occur in SBRT?
Reference:Clark BG, Brown RJ, Ploquin J, Dunscombe P. Patient safety improvements in radiation treatment through 5 years of incident learning. Pract Radiat Oncol. Jul-Sep 2013;3(3):157-163.
Choice A:Simulation
Choice B:Treatment planning
Choice C:Patient setup
Choice D:Patient treatment
Question 6: According to AAPM and ASTRO reports which of the following technology is required for delivering SBRT treatments?
Reference:Solberg T, Balter J, Benedict S, et al. Quality and safety considerations in stereotactic radiosurgery and stereotactic body radiotherapy: executive summary. Pract Radiat Oncol. 2012;2:2-9.
Choice A:Diode scanning for commissioning.
Choice B:Treatment planning with Monte Carlo.
Choice C:Volumetric on-line imaging.
Choice D:4D-CT during simulation.
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