MDCB Practice Set 3 - Test 9 Exam
Questions With 100% Verified Answers
1. Which type(s) of DVH shows the volume receiving a dose within
a specified dose range?
A. integral
B. cumulative
C. organ
D. differential -
correct answer ✅D
2. Which one of the following dose volume histogram (DVH) results
for a pancreatic treatment plan
of conventional fractionation meets QUANTEC recommended dose
tolerances?
A. 75% of the left kidney will receive 30 Gy.
B. 50% of the right kidney will receive 40 Gy.
C. 50% of the liver will receive 42 Gy.
D. 25% of the stomach will receive 45 Gy. -
correct answer ✅D
3. Which of the following choices is the correct descriptor of the
internal target volume (ITV), as
defined by the ICRU Report #62?
,MDCB Practice Set 3 - Test 9 Exam
Questions With 100% Verified Answers
A. GTV + Breathing Motion + Setup Margin
B. CTV + Internal Motion + Setup Margin
C. (C) CTV + Internal Motion
D. (D) GTV + Breathing Motion -
correct answer ✅C
4. Which of the following is true regarding clinical electron beams?
A. High energy electrons lose energy at a rate of approximately 2
MeV per cm of water or
soft tissue.
B. The depth of the 80% isodose occurs at approximately 1/4 of the
electron energy in
MeV.
C. The depth of the 90% isodose occurs at approximately 1/3 of the
electron energy in
MeV.
D. The practical range of electrons (in cm of water) is approximately
2 times the energy in
MeV. -
correct answer ✅A
, MDCB Practice Set 3 - Test 9 Exam
Questions With 100% Verified Answers
5. What factors are instrumental in determining the dose
uniformity in equally weighted parallel
opposed beams?
A. beam energy, tissue inhomogeneity and patient thickness
B. beam energy, patient thickness and tissue maximum ratio
C. beam flatness, patient thickness and collimator scatter
D. patient thickness, inhomogeneity and collimator scatter -
correct answer ✅A
6. A patient is normally treated with 18 MV photons 100 cm SAD
linear accelerator. The machine
breaks down and the patient is moved to a 6 MV 100 cm SAD linear
accelerator. Using the same
patient set up, the medical dosimetrist should consider doing which
of the following?
A. Recompute an isodose distribution
B. Recontour all normal structures
C. Change MLC blocking
D. Change the field size -
correct answer ✅A
Questions With 100% Verified Answers
1. Which type(s) of DVH shows the volume receiving a dose within
a specified dose range?
A. integral
B. cumulative
C. organ
D. differential -
correct answer ✅D
2. Which one of the following dose volume histogram (DVH) results
for a pancreatic treatment plan
of conventional fractionation meets QUANTEC recommended dose
tolerances?
A. 75% of the left kidney will receive 30 Gy.
B. 50% of the right kidney will receive 40 Gy.
C. 50% of the liver will receive 42 Gy.
D. 25% of the stomach will receive 45 Gy. -
correct answer ✅D
3. Which of the following choices is the correct descriptor of the
internal target volume (ITV), as
defined by the ICRU Report #62?
,MDCB Practice Set 3 - Test 9 Exam
Questions With 100% Verified Answers
A. GTV + Breathing Motion + Setup Margin
B. CTV + Internal Motion + Setup Margin
C. (C) CTV + Internal Motion
D. (D) GTV + Breathing Motion -
correct answer ✅C
4. Which of the following is true regarding clinical electron beams?
A. High energy electrons lose energy at a rate of approximately 2
MeV per cm of water or
soft tissue.
B. The depth of the 80% isodose occurs at approximately 1/4 of the
electron energy in
MeV.
C. The depth of the 90% isodose occurs at approximately 1/3 of the
electron energy in
MeV.
D. The practical range of electrons (in cm of water) is approximately
2 times the energy in
MeV. -
correct answer ✅A
, MDCB Practice Set 3 - Test 9 Exam
Questions With 100% Verified Answers
5. What factors are instrumental in determining the dose
uniformity in equally weighted parallel
opposed beams?
A. beam energy, tissue inhomogeneity and patient thickness
B. beam energy, patient thickness and tissue maximum ratio
C. beam flatness, patient thickness and collimator scatter
D. patient thickness, inhomogeneity and collimator scatter -
correct answer ✅A
6. A patient is normally treated with 18 MV photons 100 cm SAD
linear accelerator. The machine
breaks down and the patient is moved to a 6 MV 100 cm SAD linear
accelerator. Using the same
patient set up, the medical dosimetrist should consider doing which
of the following?
A. Recompute an isodose distribution
B. Recontour all normal structures
C. Change MLC blocking
D. Change the field size -
correct answer ✅A
