MDCB Practice Set 3 Questions with

MDCB Practice Set 3 Questions with Complete Solutions (Latest 2025) Which type(s) of DVH shows the volume receiving a dose within a specified dose range?

• integral
• cumulative
• organ
• differential - Correct Answers ✅D. differential

Which one of the following dose volume histogram (DVH) results for a pancreatic treatment plan of conventional fractionation meets QUANTEC recommended dose tolerances?

• 75% of the left kidney will receive 30 Gy.
• 50% of the right kidney will receive 40 Gy.
• 50% of the liver will receive 42 Gy.
• 25% of the stomach will receive 45 Gy. - Correct Answers

✅D. 25% of the stomach will receive 45 Gy.Which of the following choices is the correct descriptor of the internal target volume (ITV), as defined by the ICRU Report #62?

• GTV + Breathing Motion + Setup Margin
• CTV + Internal Motion + Setup Margin
• CTV + Internal Motion
• GTV + Breathing Motion - Correct Answers ✅C. CTV +

Internal Motion 1 / 2

MDCB Practice Set 3 Questions with Complete Solutions (Latest 2025) Which of the following is true regarding clinical electron beams?

• High energy electrons lose energy at a rate of

approximately 2 MeV per cm of water or soft tissue.

• The depth of the 80% isodose occurs at approximately 1/4

of the electron energy in MeV.

• The depth of the 90% isodose occurs at approximately 1/3

of the electron energy in MeV.

• The practical range of electrons (in cm of water) is

approximately 2 times the energy in MeV. - Correct Answers ✅A. High energy electrons lose energy at a rate of approximately 2 MeV per cm of water or soft tissue.What factors are instrumental in determining the dose uniformity in equally weighted parallel opposed beams?

• beam energy, tissue inhomogeneity and patient thickness
• beam energy, patient thickness and tissue maximum ratio
• beam flatness, patient thickness and collimator scatter
• patient thickness, inhomogeneity and collimator scatter -

Correct Answers ✅A. beam energy, tissue inhomogeneity and patient thickness 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

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