Lauras Exam 4

Question 1

Which machine components are located within the gantry?

Answer 1

Electron gun
Accelerator structure

Question 2

Which part of the machine houses the ion chambers?

Answer 2

Gantry Head

Question 3

List the order of machine parts in the linac head for a photon treatment:

Answer 3

Target, primary collimators, flattening filter, ion chamber, secondary collimators, MLCs
TPFISM

Question 4

Which agency is responsible for regulating the manufacturing of linear accelerators?

Answer 4

FDA

Question 5

PPD is affected by:

Answer 5

Energy
Depth
SSD

Question 6

Which part of the machine houses the electron gun?

Answer 6

Gantry

Question 7

Which organ does NOT have a tolerance dose of 4500 cGy?

Answer 7

Heart

Question 8

Which machine components are located within the drive stand?

Answer 8

Klystron
Circulator

Question 9

When viewing an axial image, which directions can the patient be moved in?

Answer 9

Ant, Post
Left, Right

Question 10

Which type of breast surgery removes chest wall muscles?

Answer 10

Radical Mastectomy

Question 11

Removal of breast, tissue, areola, nipple

Answer 11

Total Mastectomy

Question 12

What part of the machine houses the Klystron?

Answer 12

Drive stand

Question 13

What is the typical gantry angle used for supraclavicular fields?

Answer 13

10-15 degrees

Question 14

When viewing sagittal images, which directions can the patient be moved in?

Answer 14

Ant, Post
Sup, Inf

Question 15

Compared to machines that only treat complex treatments, machines that treat SBRT treatments have:

Answer 15

Smaller laser tolerances

Question 16

If MLCs move only when the beam turns off, this is known as:

Answer 16

Step and shoot

Question 17

The most common pathology for tumors in the urethra are?

Answer 17

Squamous

Question 18

Most common pathology for ureters is:

Answer 18

Transitional cell

Question 19

Which device is MR safe?

Answer 19

aneurysm clip

-no epids, hearing aids, breast balloons

Question 20

What is the laser tolerance for a linac that performs IMRT treatments?

Answer 20

1.5mm

Question 21

What is the purpose of imaging studies before brachytherapy?

Answer 21

To identify the location and size of the tumor
To ensure that the radioactive source is placed in the correct location
To minimize the damage to healthy tissue

Question 22

Which of the following would be a reason why supraclavicular fields are included in breast treatments?

Answer 22

Stage N2-N3
4+ positive axillary lymph nodes

Question 23

Which factor has an inverse relationship with PDD?

Answer 23

Depth

Question 24

Which material would have the highest stopping power for electrons?

Answer 24

lead

Question 25

How is field size related to PDD?

Answer 25

As field size increases, PDD increases due to scatter

Question 26

The patient is positioned head first prone for a PA treatment. The patient is accidentally treated with a posterior isoshift of 3 cm. How does this affect the dose to the planned isocenter?

Answer 26

Planned iso is underdosed

Question 27

Atomic nuclei with differing Z numbers, but the same A number?

Answer 27

isobar

Question 28

Which QA tests should be performed at least daily?

Answer 28

lasers output NOT Light field/Radiation field coincidence Emergency off buttons

Question 29

Which of the following particles has the highest ionizing power?

Answer 29

alpha

Question 30

Which of the following types of radiation can be detected using a Geiger-Muller counter?

Answer 30

Gamma

Question 31

What does CPT stand for in medical billing and coding?

Answer 31

Current procedural terminology

Question 32

What is the standard fractionation scheme for whole brain radiation therapy?

Answer 32

30 Gy x 10 fx

Question 33

PDD vs. PPD

Answer 33

PDD= energy, field size, SSD PPD= energy, field size, depth