MDCB Practice test #1 2026
Which type of DVH shows the volume receiving a dose within a specified dose range? -
answer differential
Which one of the following DVH results for a pancreatic treatment plan of conventional
fractionation meets QUANTEC recommended dose tolerances? - answer. 25% of the
stomach will receive 45 Gy.
Which of the following is TRUE regarding clinical electron beams? - answerHigh 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? - answerbeam energy, tissue inhomogeneity and patient
thickness
Which of the following computer algorithms can most accurately account for the dose
calculation uncertainty in the interface region between inhomogeneous materials for
photon calculations? - answerMonte Carlo method
An IMRT technique in which the patient is treated slice by slice by intensity-modulated
beams in a manner analogous to CT imaging is called: - answerhelical LINAC.
Which one of the following is the best thermal neutron absorber? - answerboronated
polyethylene
Relative skin dose from a megavoltage photon beam is increased by which of the
following? - answerincreasing the thickness bolus material used
The risk of symptomatic radiation pneumonitis is: - answerincreased if certain
chemotherapy agents are used.
Arrow #2 points to which of the following? - answerTransverse colon
According to the DVH shown, what is the V20 of the total lung? - answer. 27%
DVHs can confirm which of the following? - answerThe normal tissue tolerances are
respected.
When comparing identical (IMRT) treatment plans, one delivered with sliding window
and the other delivered with step-and-shoot, the sliding window treatment will most
likely have which of the following? - answerhigher MU and shorter tx time
Which type of DVH shows the volume receiving a dose within a specified dose range? -
answer differential
Which one of the following DVH results for a pancreatic treatment plan of conventional
fractionation meets QUANTEC recommended dose tolerances? - answer. 25% of the
stomach will receive 45 Gy.
Which of the following is TRUE regarding clinical electron beams? - answerHigh 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? - answerbeam energy, tissue inhomogeneity and patient
thickness
Which of the following computer algorithms can most accurately account for the dose
calculation uncertainty in the interface region between inhomogeneous materials for
photon calculations? - answerMonte Carlo method
An IMRT technique in which the patient is treated slice by slice by intensity-modulated
beams in a manner analogous to CT imaging is called: - answerhelical LINAC.
Which one of the following is the best thermal neutron absorber? - answerboronated
polyethylene
Relative skin dose from a megavoltage photon beam is increased by which of the
following? - answerincreasing the thickness bolus material used
The risk of symptomatic radiation pneumonitis is: - answerincreased if certain
chemotherapy agents are used.
Arrow #2 points to which of the following? - answerTransverse colon
According to the DVH shown, what is the V20 of the total lung? - answer. 27%
DVHs can confirm which of the following? - answerThe normal tissue tolerances are
respected.
When comparing identical (IMRT) treatment plans, one delivered with sliding window
and the other delivered with step-and-shoot, the sliding window treatment will most
likely have which of the following? - answerhigher MU and shorter tx time
