Pregunta 1
Pregunta
What does radiolucent mean?
Respuesta
-
Opaque to x-rays
-
Invisible to x-rays
Pregunta 2
Pregunta
What density is radiopaque?
Pregunta 3
Pregunta
Are all of these labels correct?
Pregunta 4
Respuesta
-
Focusing cup
-
Filament
-
Target (anode)
-
Rotor
Pregunta 5
Respuesta
-
Focusing cup
-
Filament
-
Target (anode)
-
Rotor
Pregunta 6
Respuesta
-
Glass envelope
-
Filament
-
Electrons
-
Bearings
Pregunta 7
Respuesta
-
Glass envelope
-
Filament
-
Electrons
-
Bearings
Pregunta 8
Respuesta
-
Glass envelope
-
Electrons
-
Filament
-
Bearings
Pregunta 9
Pregunta
What is the heel effect?
Respuesta
-
The beam is more concentrated on the cathode side
-
The beam is more concentrated on the anode side
-
The imaginary line following the centremost part of the beam
-
The imaginary line following the outermost part of the beam
Pregunta 10
Pregunta
What is the central ray?
Respuesta
-
The beam is more concentrated on the cathode side
-
The beam is more concentrated on the anode side
-
An imaginary line following the centremost part of the beam
-
An imaginary line following the outermost part of the beam
Pregunta 11
Pregunta
Controlling the size of the beam is a legal requirement
Pregunta 12
Pregunta
Keeping the beam large makes the image sharper
Pregunta 13
Pregunta
If a smaller volume of tissue is irradiated, is a smaller or larger scatter generated?
Pregunta 14
Pregunta
Is scatter desirable?
Pregunta 15
Pregunta
What structure controls the beam?
Respuesta
-
Collimator
-
Target (anode)
-
Filament
-
Grid
Pregunta 16
Pregunta
How does a collimator work?
Pregunta 17
Pregunta
Where should the patient be placed in regards to the Bucky and tube?
Respuesta
-
Close to the Bucky, far away from the tube
-
Far away from the Bucky, close to the tube
-
Close to the Bucky, close to the tube
-
Far away from the Bucky, far away from the tube
Pregunta 18
Pregunta
What is true regarding the beam passing through the patient?
Respuesta
-
Some x-rays are absorbed and stop their travel
-
Some are scattered and continue to travel
-
All scattered x-rays continue to travel in the correct direction
-
A remnant beam exits the patient
-
The remnant beam is accompanied by any scatter travelling in a similar direction
-
All scattered x-rays will accompany the remnant beam
Pregunta 19
Pregunta
What are correct facts regarding the Bucky?
Respuesta
-
It is placed immediately in front of the patient
-
It has a tray to hold the receptor
-
It has a grid to allow as much scatter as possible to reach the receptor
-
It has a grid to prevent as much scatter as possible from reaching the receptor
-
There are different types of grids
Pregunta 20
Respuesta
-
Collimator
-
Bucky
-
Grid
-
Receptor
-
Filament
Pregunta 21
Respuesta
-
Collimator
-
Bucky
-
Grid
-
Receptor
-
Filament
Pregunta 22
Respuesta
-
Collimator
-
Bucky
-
Grid
-
Receptor
-
Filament
Pregunta 23
Pregunta
What is the grid ratio?
Pregunta 24
Pregunta
How are the strips placed in a non-focussed grid?
Respuesta
-
Parallel
-
Angled - matches angles of the x-rays exiting the patient, must be used with the tube at a specific distance away
-
Moving - increases efficiency and hides any lines that may be caused by the grid material
Pregunta 25
Pregunta
How are the strips placed in a focussed grid?
Respuesta
-
Parallel
-
Angled - matches angles of the x-rays exiting the patient, must be used with the tube at a specific distance away
-
Moving - increases efficiency and hides any lines that may be caused by the grid material
Pregunta 26
Pregunta
How are the strips placed in a reciprocating grid?
Respuesta
-
Parallel
-
Angled - matches angles of the x-rays exiting the patient, must be used with the tube at a specific distance away
-
Moving - increases efficiency and hides any lines that may be caused by the grid material
Pregunta 27
Pregunta
What are the correct facts regarding receptors?
Respuesta
-
Device used to capture the remnant beam
-
Device used to capture the scatter beams
-
Can be a film or digital system
Pregunta 28
Pregunta
What are correct facts regarding film receptors?
Respuesta
-
A single piece of film is supported in a cassette
-
A film is typically one-sided
-
There is an intensifying screen on one side of the film
-
The film needs to be processed in a darkroom so the image becomes visible
Pregunta 29
Pregunta
What are correct facts regarding a digital receptor?
Respuesta
-
A single sided receptor array supported in a cassette
-
There is also a filament in the cassette
-
The image has already been processed electronically
-
The latent image is formed directly on the receptor, which reacts to the x-ray beam
Pregunta 30
Pregunta
With either film or digital, you end up with an image which can be viewed on either a light box (film) or computer screen (digital)
Pregunta 31
Pregunta
What is the kVP (kilovolts peak)?
Respuesta
-
Controls the penetrating power of the x-ray beam
-
Controls the number of electrons crossing from the cathode to the anode
-
The time that the electrons are allowed to cross the tube for
Pregunta 32
Pregunta
What is the mA (milliamperes)?
Respuesta
-
Controls the number of electrons crossing from the cathode to the anode
-
Controls the penetrating power of the x-ray beam
-
The time that the electrons are allowed to cross the tube for
Pregunta 33
Pregunta
What are x-ray factors expressed in?
Pregunta 34
Pregunta
Where is the x-ray created?
Pregunta 35
Pregunta
How fast does a rotating anode spin per minute?
Respuesta
-
3400 revolutions
-
3000 revolutions
-
3200 revolutions
-
3600 revolutions
Pregunta 36
Pregunta
Why does the anode spin?
Pregunta 37
Pregunta
What facts are correct regarding Bremsstrahlung?
Respuesta
-
The x-ray beam is heterogeneous
-
The energy of the Bremsstrahlung x-ray will vary depending on how far an electron penetrates a target atom
-
The energy of the Bremsstrahlung x-ray will vary depending on how quickly an electron penetrates a target atom
-
X-rays of a single energy will be produced
-
kVP controls the range of energies produced
-
mA controls the range of energies produced
-
Interactions in the outer part of the atom generate weaker x-rays, the inner part is stronger
-
Interactions in the outer part of the atom generate stronger x-rays, the inner part is weaker
-
X-ray Bremsstrahlung comprises a range of energies from an identifiable maximum to an indeterminate minimum
Pregunta 38
Pregunta
How do you control Bremsstrahlung?
Respuesta
-
kVp controls the maximum energy within the beam
-
kVp controls the minimum energy within the beam
-
mA and s control the number of photons of energy within the beam
-
mA and s control the penetration rate of photons within the beam
Pregunta 39
Pregunta
What are the two major parts on the cathode side of the tube?
Pregunta 40
Pregunta
What does the filament release when it's heated?
Respuesta
-
Cloud of electrons (thermionic emission)
-
Cloud of protons (thermionic emission)
-
Cloud of atoms (thermionic emission)
Pregunta 41
Pregunta
Is the focusing cup positively or negatively charged?
Pregunta 42
Pregunta
Why does the focusing cup condense the electron cloud?
Pregunta 43
Pregunta
What directions are Bremsstrahlung radiation produced?
Respuesta
-
All directions
-
Forwards
-
Backwards
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Laterally
Pregunta 44
Pregunta
What is the only part of the beam required?
Respuesta
-
Beam travelling towards the patient
-
Beam travelling away from the patient
-
Beam travelling upwards through the patient
-
Beam travelling downwards through the patient
Pregunta 45
Pregunta
Why is there an oil filled space between the housing and the tube?
Respuesta
-
Absorbs the heat that is produced
-
Reduces the scatter
-
Decreases the amount of electron penetration
-
Decreases the number of electrons of energy in the beam
Pregunta 46
Pregunta
What is the role of the collimator?
Pregunta 47
Pregunta
If the beam is restricted, is the scatter radiation increased or decreased?
Pregunta 48
Pregunta
What are correct facts regarding scatter?
Respuesta
-
Restricting the beam reduces scatter
-
Restricting the beam increases scatter
-
Reducing scatter radiation improves image quality
-
Reducing scatter radiation reduces image quality
-
Restricting the beam reduces the patient's radiation dose
-
Restricting the beam increases the patient's radiation dose
Pregunta 49
Pregunta
What is scatter often referred to as?
Respuesta
-
Compton scatter
-
Compton electron
-
Recoil electron
Pregunta 50
Pregunta
Where can the outer shell electron gain some energy from and what does it become?
Respuesta
-
Photon - becomes recoil/Compton electron
-
Neutron - becomes recoil/Compton electron
-
Electron - becomes Compton scatter
-
Photon - becomes Compton scatter
Pregunta 51
Pregunta
What happens to the x-ray photon when it collides with an outer shell electron?
Respuesta
-
Retains the remainder energy, but changes course (scatters) in a random direction
-
Increases its energy, but changes course (scatters) in a random direction
-
Decreases its energy, but changes course (scatters) in a random direction
Pregunta 52
Pregunta
Does the kVp value have a direct effect on scatter, regarding amount produced and direction of scatter?
Pregunta 53
Pregunta
Does a collimator compress and focus the x-ray beam?
Pregunta 54
Pregunta
A collimator works by 2 pairs of lead leaves which absorb or reflect the x-ray beam
Pregunta 55
Pregunta
Does a low kVp increase or decrease the scatter formation?
Pregunta 56
Pregunta
If there is less scatter, how does the image look?
Pregunta 57
Pregunta
What is needed to to counteract the less image?
Pregunta 58
Pregunta
Why can a high mA be bad for a patient?
Pregunta 59
Pregunta
What does a high kVp affect?
Pregunta 60
Pregunta
What is good contrast?
Respuesta
-
Black
-
White
-
Grey
-
Low kVp
-
High kVp
Pregunta 61
Pregunta
What is optical density?
Pregunta 62
Pregunta
How do you maintain optical density?
Pregunta 63
Pregunta
What do you increase the kVp by to double the optical density?
Pregunta 64
Pregunta
What do you increase the mA by to double the optical density?
Pregunta 65
Pregunta
What are correct facts regarding the control panel?
Respuesta
-
Allows you to set kVp, mA and s
-
Allows upright v recumbent grids to be selected
-
Allows exposure to be made
-
Allows AEC (Automatic Exposure Chamber) and exact chamber to be selected
Pregunta 66
Pregunta
How many target sizes are there?
Pregunta 67
Pregunta
What size target is used for smaller exposures?
Respuesta
-
Smaller target
-
Larger target
Pregunta 68
Pregunta
What are correct facts regarding target size
Respuesta
-
Appropriate target sizes are used to avoid overheating the target material
-
The target size affects the quality of the image
-
The smaller target produces a larger penumbra around the image - causing it to looked blurred
-
The larger target produces a larger penumbra around the image - causing it to looked blurred
-
The larger target is used for smaller exposures
-
There are commonly 5 targets in an x-ray tube
Pregunta 69
Pregunta
The penumbra increases as the subject-receptor distance decreases
Pregunta 70
Pregunta
The penumbra decreases as the target-subject distance increases
Pregunta 71
Pregunta
The distance between the target and the subject, and the subject and receptor will affect the image
Pregunta 72
Pregunta
What is the subject-receptor distance also known as, and what size is desirable?
Respuesta
-
Object-image distance (OID) - small
-
Object-image distance (OID) - large
-
Source-image distance (SID) - small
-
Source-image distance (SID) - large
Pregunta 73
Pregunta
What benefits does a small OID give?
Pregunta 74
Pregunta
What distance is desirable for the Source-image distance (SID)?
Pregunta 75
Pregunta
What benefits are there with a long SID?
Pregunta 76
Pregunta
Is distortion undesirable in an x-ray image?
Pregunta 77
Pregunta
Why does distortion occur?
Respuesta
-
When there is too much energy penetrating the patient
-
When the anatomy lies at an inappropriate angle to the receptor, or vice versa
Pregunta 78
Pregunta
What factors make an x-ray optimal?
Respuesta
-
Collimate the beam to the relevant anatomy
-
Select a large target size
-
Have a short OID
-
Have a long OID
-
Have a short SID
-
Have a long SID
-
Selecting kVp to allow adequate penetration
-
Selecting mA ensuring enough photons get through the subject
-
Consider anatomy to the receptor
-
Ensuring balance of kVp and mAs to a suitable level of contrast
Pregunta 79
Pregunta
How can the Bucky be placed?
Respuesta
-
Vertically
-
Horizontally
-
Diagonally
Pregunta 80
Pregunta
What facts are correct regarding the Bucky?
Respuesta
-
Designed to hold a receptor
-
There is only one type of Bucky
-
It cannot be moved into various positions
-
It holds an anti-scatter grid
-
It holds the receptor close to the grid and the grid close to the protective front plate
-
It can contain automatic exposure chambers
Pregunta 81
Pregunta
What is the role of an anti-scatter grid?
Respuesta
-
To eliminate as much scatter as possible as it exits the patient and before it reaches the receptor
-
To eliminate as much scatter as possible as it enters the patient
-
To focus the scatter before it reaches the receptor
-
To decrease the amount of radiation to the patient
Pregunta 82
Pregunta
What is the grid ratio?
Pregunta 83
Pregunta
What is the grid frequency?
Pregunta 84
Pregunta
What type of lines does a linear grid have?
Respuesta
-
Parallel
-
Diagonal
-
Criss-cross
Pregunta 85
Pregunta
Where is a linear grid most efficient?
Pregunta 86
Pregunta
What is the cheapest and easiest grid to make?
Respuesta
-
Linear/parallel grid
-
Focused
-
Crossed
-
Static
-
Moving/reciprocating
Pregunta 87
Pregunta
What type of grid has angled strips?
Respuesta
-
Focused
-
Linear/parallel
-
Static
-
Crossed
-
Moving/reciprocating
Pregunta 88
Pregunta
Which portion of the grid matches the direction of the beam?
Pregunta 89
Pregunta
What is the aim of a reciprocating grid?
Respuesta
-
Blur the shadows of the grid strips so they're not visible on the image
-
To decrease the amount of radiation
-
To improve the contrast of the image
Pregunta 90
Pregunta
What types of strips can a reciprocating grid have?
Pregunta 91
Pregunta
Why are crossed grids commonly found in general radiography practice?
Respuesta
-
They are extremely effective at scatter removal, as they're made up for 2 grids running at 90 degrees to each other
-
They are extremely effective at scatter removal, as they're made up for 4 grids running at 90 degrees to each other
-
They are the cheapest form of imaging
-
Difficult to use as the central part of the beam must be perpendicular and central to the grids
Pregunta 92
Pregunta
Why is an air gap beneficial instead of a grid?
Pregunta 93
Pregunta
What does the cassette hold close together?
Pregunta 94
Pregunta
What do the phosphors act as in the intensifying screens?
Pregunta 95
Pregunta
What does the phosphor layer contain?
Pregunta 96
Pregunta
What is spectral matching?
Respuesta
-
The emulsion is set to match the colour of light being emitted by the intensifying screens
-
The base is lightly tinted (pale blue or grey) to match the colour of light being emitted by the intensifying screens
-
Silver halide crystals are active in the emulsion
-
The emulsions are covered by a fine, translucent protective layer
Pregunta 97
Pregunta
A digital receptor has intensifying screens or film and an area for patient information
Pregunta 98
Pregunta
What facts are correct regarding digital receptors?
Respuesta
-
Cassette is a rigid, light-tight and dust-proof support
-
There is an area for patient information
-
There is a single sided imaging plate
-
There is a double sided imaging plate
-
The latent image is still invisible and needs to be processed
Pregunta 99
Pregunta
What is the order in an intensifying screen?
Pregunta 100
Pregunta
What is the base made of?
Respuesta
-
Strong, flexible, chemically inert material (e.g. plastic)
-
Weak, flexible, chemically inert material (e.g. plastic)
-
Strong, solid, chemically inert material (e.g. plastic)
-
Weak, solid, chemically inert material (e.g. plastic)
Pregunta 101
Pregunta
The higher the speed, the more re-active the screen is
Pregunta 102
Pregunta
What layers does the x-ray beam pass through?
Respuesta
-
Base
-
Reflective layer
-
Protective layer
-
Phosphor layer
Pregunta 103
Pregunta
Does the x-ray beam interact with the phosphor layer to emit light?
Pregunta 104
Pregunta
Why do the phosphors have a high atomic number?
Respuesta
-
So the x-ray absorption is high
-
So the x-ray absorption is low
-
So the light emitted from the x-ray beam is high
-
So the light emitted from the x-ray beam is low
Pregunta 105
Pregunta
What is the x-ray conversion efficiency?
Pregunta 106
Pregunta
How much afterglow is optimal?
Pregunta 107
Pregunta
Should the phosphors be affected by heat, humidity or any other environmental effects?
Pregunta 108
Pregunta
What do the emulsion layers of the intensifying screens contain that react to x-rays?
Respuesta
-
Crystals
-
Electrons
-
Protons
-
Light waves
Pregunta 109
Pregunta
What size crystals produce finer, more contained light?
Pregunta 110
Pregunta
What needs to happen in screens with small crystals?
Pregunta 111
Pregunta
Where are fine crystal screens most commonly used?
Pregunta 112
Pregunta
What direction is light emitted from the phosphors?
Respuesta
-
All directions
-
Diagonally
-
Vertically
-
Horizontally
Pregunta 113
Pregunta
What is the role of the reflective layer?
Respuesta
-
Redirects the light emitted from the phosphors, so as much light as possible is travelling towards the film
-
Redirects the scatter away from the receptor, so a minute amount of scatter is travelling towards the film
Pregunta 114
Pregunta
What percentage of the image is formed by the direct interaction of x-rays with the film?
Pregunta 115
Pregunta
What is the role of the protective layer of the intensifying screen?
Respuesta
-
Fine translucent layer to protect the phosphors from dust and abrasion
-
Thick translucent layer to protect the phosphors from dust and abrasion
-
Fine coloured layer to protect the phosphors from dust and abrasion
Pregunta 116
Pregunta
What is the active ingredient in the emulsion of a film?
Respuesta
-
Silver halide crystals
-
Gold halide crystals