Deck 21: Simulator Design

Question 1

________________________ takes into consideration how an area on the other side of an irradiated wall is going to be used.

A) Workload
B) Occupancy factor
C) Use factor
D) Barrier factor

Answer 1

B
Occupancy factor will vary if the room adjacent to the simulator is a closet or has an employee there for 40 hours per week.

Question 2

A light field radiation field coincidence test is performed in all instances except:

A) when a bulb is replaced
B) when the mirror is realigned
C) when the radiation field appears off center from the film

Answer 2

C
A light field radiation field coincidence test is not performed if the radiation field appears off center from the film.The image intensifier is probably off center.

Question 3

Light photons are produced and transmitted electronically through to a video image at the:

A) output phosphor
B) tube housing
C) photocathode
D) focusing lenses

Answer 3

A
The light photons are converted from electrons at the output phosphor,which is then converted into an electronic image on a television screen.

Question 4

The patient couch table top is created out of this material,which has a low density and low x-ray absorption:

A) plastic carbonate
B) carbon fiber
C) steel
D) polystyrene

Question 5

In the conventional simulator,the _____________ represents the radiation field.

A) blades
B) wires
C) ODI
D) collimator assembly

Question 6

To reduce magnification during fluoroscopy,the image intensifier should be:

A) moved as close to the patient as possible
B) moved as far as possible from the patient
C) rotated in the direction of the central ray
D) centered

Question 7

The accessory holder on the simulator may serve which of the following purposes?
I)function as an electron cone adapter
II)simulate custom block verification
III)absorb scatter radiation from thicker body parts
IV)provide scanning movements for the imaging system

A) I and II only
B) I and III only
C) II and IV only
D) I,II,III,and IV

Question 8

Which of the following represents the path of a photon when it enters the image intensifier?

A) input phosphor,electrostatic lenses,photocathode,anode,output screen
B) input phosphor,photocathode,electrostatic lenses,anode,output screen
C) input phosphor,anode,electrostatic lenses,photocathode,output screen
D) anode,input phosphor,electrostatic lenses,photocathode,output screen

Question 9

Conventional simulators are designed to simulate the ____________,geometric,and optical properties of a variety of treatment units.

A) x-ray
B) mechanical
C) comfort
D) linear design

Question 10

Positioning lasers are located: I.side (lateral)
II)overhead
III)sagittal
IV)coronal

A) I and II
B) I,II,and III
C) II and III
D) all of the above

Question 11

A light field radiation field coincidence test verifies:

A) that the light from the blades represents the radiation field
B) that the field wires define the radiation field
C) the symmetry of the radiation beam
D) all of the above

Question 12

_____________________ takes into consideration how much a machine will run in a normal week.

A) Workload
B) Occupancy factor
C) Use factor
D) Barrier factor

Question 13

Which of the following is true about an isocenter?
I)It is a single point in space.
II)The gantry rotates around the isocenter.
III)The axis of gantry rotation,collimator rotation,and treatment couch rotation meet.
IV)Lasers are aligned at the isocenter.

A) I and II
B) II and III
C) III and IV
D) I,II,III,and IV

Question 14

When determining the shielding requirements for a simulation room,thicker shielding is needed in the _____________.

A) primary walls
B) secondary walls
C) tertiary walls
D) ceiling

Question 15

One 50-keV photon at the input screen can be converted into _____________ light photons at the output screen.

A) 10,000
B) 20,000
C) 100,000
D) 200,000

Question 16

The conventional simulator can define treatment fields by using:

A) blades
B) wires
C) ODI
D) collimator assembly

Question 17

Digital fluoroscopy is similar to conventional fluoroscopy; however,there is a ________________ to transmit the electrical charge.

A) charge capture device
B) computer capture detector
C) computer coupled detector
D) charge coupled device

Question 18

Most patient support assemblies can support approximately ____ lbs.

A) 250
B) 350
C) 450
D) 550

Question 19

When the primary x-ray beams strike the input screen of the image intensifier,what is emitted?

A) electrons
B) light
C) photons
D) protons

Question 20

The ___________________ in the image intensifier emits electrons when it is stimulated by light photons.

A) input phosphor
B) output phosphor
C) photocathode
D) electrostatic lenses

Question 21

As recommended by Martin,to produce a high-quality digital radiograph,slice thickness and spacing should be ___ mm through the region containing the tumor.

A) 1
B) 2
C) 3
D) 4

Question 22

The matrix size is determined by the number of:

A) voxels
B) Hounsfield units
C) detectors on the scanner
D) pixels

Question 23

The difference in completing an axial scan as compared to spiral CT is that the:

A) aperture size is larger in an axial scanner
B) detector size is larger in the spiral CT scanner
C) gantry is rotating in a diagonal
D) table moves for the spiral CT

Question 24

CT numbers are also known as:

A) Hounsfield units
B) Godfrey units
C) attenuation coefficient units

Question 25

The CT number for dense bone is:

A) -1000
B) -100
C) 0
D) 1000

Question 26

As the field of view increases and the matrix size remains constant,the spatial resolution:

A) increases
B) decreases
C) stays the same

Question 27

A(n)____________ allows the computed tomography (CT)x-ray tube to rotate in a continuous motion without the concern of cables becoming tangled.

A) spiral ring
B) slip ring
C) aperture ring
D) electrical power ring

Question 28

The CT number for water is:

A) -1000
B) -100
C) 0
D) 1000

Question 29

Most CT scanners today are _______-generation imaging systems.

A) first
B) second
C) third
D) fourth