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Neutron

Which of the following particles is used to bombard stable Cobalt-59 in order to transform it into Cobalt-60 and emits gamma rays?

Grenz-ray therapy

Which of the following therapy units is used to describe treatment with beams of very soft (low-energy) x-rays produced at potentials below 20 kV and has a very low depth of penetration?

Superficial therapy

Which of the following therapy units is used to treat with x-rays produced at potentials ranging from 50 to 150 kV?

Contact therapy

Which of the following therapy units is used to treat at potentials of 40 to 50 kV and facilitates irradiation of accessible lesions at very short source (focal spot) to surface distances (SSD)?

Supervoltage therapy

Which of the following therapy units is used to treat in the range of 500 to 1,000 kV?

Van de Graaff

Which of the following radiotherapy units is used to have an electrostatic accelerator designed to accelerate electrons to produce high-energy x-rays, typically at 2 MV?

Microtron

Which of the following radiotherapy units is used to accelerate an electron that combines the principles of both the linear accelerator and the cyclotron?

Linear accelerator

Which of the following radiotherapy units uses high-frequency electromagnetic waves to accelerate charged particles such as electrons to high energies through a linear tube?

Cyclotron

Which of the following radiotherapy units is used as a source of high-energy protons for proton beam therapy?

Klystron

Which of the following parts of a linear accelerator amplifies microwaves?

3 mm

Which of the following measurements (in mm) is the electron beam diameter as it exits the window of the accelerator tube of a linear accelerator?

Lead

Which of the following materials is usually used as a flattening filter of a linear accelerator?

To make the beam

Which of the following statements is TRUE regarding the purpose of a flattening filter

Gamma rays

Which of the following ionizing radiations is emitted by the Co-60 machine?

Electron beam

Which of the following ionizing radiation is emitted by the linear accelerator that is intended to treat superficial lesions?

It has different radiation

Which of the following is NOT true regarding a water phantom?

Human body

Which of the following is NOT considered a phantom material?

80 cm

Which of the following Source to Skin Surface Distances (SSD) is appropriate when using a Co-60 teletherapy unit?

100 cm

Which of the following Source to Skin Surface Distances (SSD) is appropriate when using a Linear Accelerator teletherapy unit?

Radiotherapy planning

Which of the following involves the consideration of patient positioning, tumor location, critical organs, and available equipment with suitable dosimetry for patient treatment?

SAD

Which of the following refers to the distance from the source of photons to the isocenter?

Simulation

Which of the following radiation therapy processes involves the designing of immobilization devices, aligning of field centers and borders by fluoroscopy or CT, documenting treatment fields by diagnostic quality radiographs, and involving dosimetric calculations including contours, custom blocks, bolus, and constructing compensating filters?

Neutron Dosimeter

Which of the following dosimeters are sensitive to low-energy thermal neutrons with energies of between 0.02 and 50 eV?

Focal spot

Which of the following is the cause of geometric penumbra?

It produces more uniform

All of the following are reasons why Cobalt-60 is suitable for teletherapy over radium and cesium except:

I. Dermatology

II. Pretreating nickel

III. Suppress allergic

Which of the following are the clinical applications of Grenz rays in radiotherapy?

Electrostatic generator

Other term for Van de Graaff Generator:

Travelling-wave structure

Which of the following components of a linear accelerator requires a terminating or "dummy" load to prevent backward reflection of the waves?

Radiation Oncologist

Member of the radiotherapy team who is responsible for consultations, dose prescriptions, on-treatment supervision and evaluations, treatment summary reports, follow-up monitoring and evaluation of treatment outcome and morbidity:

GTV

Which of the following is defined as the visible tumor volume in the images?

50.0% bismuth, 26.7% lead, 13.3% tin, and 10.0% cadmium

Composition of a Cerrobend:

Cobalt-60

Which of the following sources is preferred in the treatment of thin regions like the head and neck, or extremities?

Electron treatment

The ICRU report no. 71 is applicable only to which type of treatment?

Multileaf collimators

Which of the following provide irregularly shaped fields as well as intensity modulation of the beam in the intensity modulated radiotherapy mode?

2 to 3 mm

Which of the following refers to the diameter of the focal spot size of the linear accelerator?

Scattering foil

Which of the following functions to spread the electron beam as well as make it uniform in cross section?

Primary collimators

It provides a fixed maximum aperture for the x-ray beam:

Jaws

Which of the following refers to a type of collimator which are movable and provide variable rectangular field sizes?

Flattening filter

Which of the following functions to make the x-ray beam intensity uniform across the field?

Monitor chambers

It functions to monitor dose delivery (when calibrated) and beam flatness:

Microtron

Which of the following radiotherapy machines combines the principle of linear accelerator and cyclotron?

Penumbra

Which of the following refers to a dose transition region near the borders of the field?

Physical

. Which of the following type of penumbra refers to the spread of dose distribution near field borders and is usually specified by the lateral width of isodose levels?

UTZ

Simulation may be performed on the following imaging modalities except:

4 to 25 MeV & 4 to 25 MV

It refers to the energies produced by a linear accelerator:

Hydrogen thyratron

The modulator contains the pulse-forming network and a high-voltage switch tube known as:

Nitrogen and CO2

What insulating gas mixture is typically used in a Van de Graaff generator?

Accelerate charged particles using high-frequency microwaves

What is the primary function of a LINAC?

Dummy load

Which structure absorbs microwaves at the end of a travelling-wave accelerator to prevent backward reflection?

Freon

What gas is used to pressurize a waveguide to prevent electrical breakdown?