MDCB EXAM QUESTIONS AND ANSWERS. A+ GRADED
GUIDE.
The measured and computer generated isodose curves should agree within:
A. +/- 3%, 2mm.
B. +/- 2%, 3mm.
C. +/- 2%, 2mm.
D. +/- 3%, 3mm.
C. +/- 2%, 2mm.
Dose variation across the field at a specified depth is referred to as:
A. medial alignment
B. dose profile
C. beam profile
D. lateral alignment
C. beam profile
An Ir-192 HDR source is being utilized in conjunction with a breast balloon for a breast treatment.
What would be the typical prescription dose per fraction for this treatment?
A. 266cGy/fx for 15fxs over 3 weeks
B. 340cGy/fx for 15fxs over 3 weeks
C. 340cGy/fx BID for 10fxs in one week
D. 385cGy/fx BID for 10fxs in one week
C. 340cGy/fx BID for 10fxs in one week
Electron boost fractions to the chestwall following mastectomy and primary photon treatments will
generally require which beam modulator to aide in dose delivery?
A. lead shielding on the skin
B. tissue-equivalent bolus
C. diode
D. infrared gating system
B. tissue-equivalent bolus
The DVH is a graphical representation of dose per CC tissue:
A. relative to a single structure.
B. weighted by tissue radio-sensitivity.
C. relative to the whole body.
D. relative to the whole body.
A. relative to a single structure.
Which cell type is most radiosensitive?
A. muscle
B. lymphocytes
, C. bone
D. connective tissue
B. lymphocytes
With LINAC based SBRT/SABR and a plan that has a 100% maximum IDL, what is the typical range of
prescription isodose line covering the PTV?
A. 40 - 60 %
B. 60 - 90 %
C. 90 - 100 %
D. > 100 %
C. 90 - 100 %
Prescriptions for dose and monitor unit calculations using Monte Carlo based treatment planning
systems should be based on dose to:
A. a single voxel.
B. an off axis point.
C. target volumes.
D. the isocenter.
C. target volumes.
Which of the methods used to reduce the impact of respiratory motion in radiotherapy results in a
loss of resolution to tumor and normal organ delineation?
A. slow CT scanning
B. inhale and exhale breath-hold CT
C. four-dimensional CT
D. respiration-accelerated CT
A. slow CT scanning
According to The AAPM TG#76 the use of respiratory management techniques is appropriate for the
patient's radiation treatment when:
A. the respiratory motion of the tumor is the same from day to day.
B. this technique reduces treatment set up errors for cancer patients.
C. when tumor motion is greater than 5mm.
D. allows physicians to identify microscopic disease.
C. when tumor motion is greater than 5mm.
The most common interaction for megavoltage photon beams in water-like tissues (Z = 7.5), is the:
A. photoelectric effect.
B. Compton effect.
C. pair production effect.
D. Rayleigh scattering effect.
B. Compton effect.
GUIDE.
The measured and computer generated isodose curves should agree within:
A. +/- 3%, 2mm.
B. +/- 2%, 3mm.
C. +/- 2%, 2mm.
D. +/- 3%, 3mm.
C. +/- 2%, 2mm.
Dose variation across the field at a specified depth is referred to as:
A. medial alignment
B. dose profile
C. beam profile
D. lateral alignment
C. beam profile
An Ir-192 HDR source is being utilized in conjunction with a breast balloon for a breast treatment.
What would be the typical prescription dose per fraction for this treatment?
A. 266cGy/fx for 15fxs over 3 weeks
B. 340cGy/fx for 15fxs over 3 weeks
C. 340cGy/fx BID for 10fxs in one week
D. 385cGy/fx BID for 10fxs in one week
C. 340cGy/fx BID for 10fxs in one week
Electron boost fractions to the chestwall following mastectomy and primary photon treatments will
generally require which beam modulator to aide in dose delivery?
A. lead shielding on the skin
B. tissue-equivalent bolus
C. diode
D. infrared gating system
B. tissue-equivalent bolus
The DVH is a graphical representation of dose per CC tissue:
A. relative to a single structure.
B. weighted by tissue radio-sensitivity.
C. relative to the whole body.
D. relative to the whole body.
A. relative to a single structure.
Which cell type is most radiosensitive?
A. muscle
B. lymphocytes
, C. bone
D. connective tissue
B. lymphocytes
With LINAC based SBRT/SABR and a plan that has a 100% maximum IDL, what is the typical range of
prescription isodose line covering the PTV?
A. 40 - 60 %
B. 60 - 90 %
C. 90 - 100 %
D. > 100 %
C. 90 - 100 %
Prescriptions for dose and monitor unit calculations using Monte Carlo based treatment planning
systems should be based on dose to:
A. a single voxel.
B. an off axis point.
C. target volumes.
D. the isocenter.
C. target volumes.
Which of the methods used to reduce the impact of respiratory motion in radiotherapy results in a
loss of resolution to tumor and normal organ delineation?
A. slow CT scanning
B. inhale and exhale breath-hold CT
C. four-dimensional CT
D. respiration-accelerated CT
A. slow CT scanning
According to The AAPM TG#76 the use of respiratory management techniques is appropriate for the
patient's radiation treatment when:
A. the respiratory motion of the tumor is the same from day to day.
B. this technique reduces treatment set up errors for cancer patients.
C. when tumor motion is greater than 5mm.
D. allows physicians to identify microscopic disease.
C. when tumor motion is greater than 5mm.
The most common interaction for megavoltage photon beams in water-like tissues (Z = 7.5), is the:
A. photoelectric effect.
B. Compton effect.
C. pair production effect.
D. Rayleigh scattering effect.
B. Compton effect.
