Test 2 hailey Flashcards
(104 cards)
1
Q
In relation to x-ray tubes, what is referred to as the insert?
A)The stem of the tube
B)The point at which the anode disc is bombarded with electrons
C)The glass encasing the anode and cathode
D)The point where the power is supplied to the tube
A
C)The glass encasing the anode and cathode
2
Q
Which of the following is NOT an advantage of a rotating anode?
A)Higher mA values possible
B)Higher kVp values possible
C)Longer exposure time possible
D)Fine focus is available at all mA values
A
D)Fine focus is available at all mA values
3
Q
The main reason that the anode is made from a tungsten alloy rather than pure tungsten is?
A)It is cheaper to produce
B)Alloyed tungsten has less chance of cracking when repetitively heated and cooled
C)It makes the anode heavier, so it spins faster
D)It is easier to cut the radial slots in to the face of the anode
A
B)Alloyed tungsten has less chance of cracking when repetitively heated and cooled
4
Q
When referring to the focal spot size on the anode, a focal spot of 0.6mm refers to?
A)The width of the area bombarded by electrons
B)The height of the area bombarded by electrons
C)The full of actual area bombarded by electrons
D)The area of penumbra produced on the x-ray
A
C)The full of actual area bombarded by electrons
5
Q
Biangular anodes work with two separate filaments which are: A)Side by side B)One above the other C)Diagonal to each other D)Wound together
A
B)One above the other
6
Q
The anode heel effect is?
A)Loss of intensity on the cathode side of the x-ray caused by the inverse square law
B)Gain of intensity on the cathode side of the x-ray caused by attenuation
C)Loss of intensity on the anode side of the x-ray caused by attenuation
D)Gain of intensity on the anode side of the x-ray caused by the inverse square law
A
C)Loss of intensity on the anode side of the x-ray caused by attenuation
7
Q
How many rotation would a standard 3000rpm anode made in an exposure of 0.04 seconds? A)1 B)2 C)3 D)4
A
B)2
8
Q
How many rotation would a high speed 8600rpm anode made in an exposure of 0.7 seconds? A)10 B)100 C)143 D)1003
A
B)100
9
Q
The inverse square law is a result of what? A)Divergence B))Attenuation C)Scatter D)Absorption
A
A)Divergence
10
Q
Using an ionisation chamber to measure the amount of radiation, an exposure al 100cm produces a reading of 76mGy. What reading would you expect if you increased the distance to 200cm? A)152 mGy B)76 mGy C)19 mGy D)8.4 mGy
A
C)19 mGy
11
Q
Using this diagram, explain the Inverse Square Law
got to question 11 on review powerpoint xray tubes
A
Intensity of exposure is inversely proportional to the distance squared from the radiation.
12
Q
During duelling practice, Ron is hit by a disarm charm which knocks him into a brick wall. He is taken to hospital, where on arrival he receives an AP chest x-ray taken at 95 kVp, 15 mAs, SID 180cm with a grid.
Two days later he has a follow up AP chest x-ray, but due to the limitations of the room size, it is taken at 95 kVp, SID 150cm, with a grid and x mAs.
Calculate the vale of x (to one decimal place).
Show your workings.
A
Answer = 0.7 x 15 = 10 mAs
13
Q
Radiation Production. This is a graph of the total radiation produced by a tungsten tube after inherent and additional filtration.
What type of radiation is A
What type of radiation is B
What is the name of the given point C
look at review powerpoint xray tube question 13
A
What type of radiation is A Characteristic radiation What type of radiation is B Bremstrahlung What is the name of the given point C eMAX
14
Q
If the cathode is heated and a potential of +35 kV was placed on it while a potential of -35 kV was placed on the anode
A)No current would flow
B)The current would flow from anode to cathode
C)The current would flow from the cathode to anode
D)No current will flow until the potential difference is greater than 40 kV?
A
B)The current would flow from anode to cathode
15
Q
The percentage of energy that is converted into heat when the freed cathode electrons interact at the anode is approximately A)100% of total energy B)97% of total energy C)90% of total energy D)85% of total energy
A
B)97% of total energy
16
Q
Raising the kVp A)Increases the size of the electrons B)Decreases the wavelengths in the beam C)Increases the quantity of photons reaching the anode D)Decreases quantum mottle in the image
A
B)Decreases the wavelengths in the beam
17
Q
The mA is
A)Controlled by the temperature of the anode
B)Affected by the length of the exposure
C)Decreased threefold when a grid is used
D)Controlled by the temperature of the filament
A
D)Controlled by the temperature of the filament
18
Q
An exposure of 80 mAs @ 70 Kvp is the same in effect as A)100 mA, 8.0 sec, @ 70 kVp B)500 mA, 0.8 sec, @ 70 kVp C)200 mA, 0.5 sec, @ 70 kVp D)400 mA, 0.2 sec, @ 70 kVp
A
D)400 mA, 0.2 sec, @ 70 kVp
19
Q
The greater the potential difference across the cathode and anode, the
A)Greater the wavelength of the x-rays in the beam
B)Smaller the wavelength of the x-rays in the beam
C)Higher the mAs will be
D)Greater the absorption can be expected, within the patient.
A
B)Smaller the wavelength of the x-rays in the beam
20
Q
A patient’s initial chest x-ray taken at 100 cm. The next day you are required to perform a follow up chest x-ray at 180 cm. What would be the required change to mAs needed to produce an image with similar density or brightness of the first radiograph?
A)Just under two fold
B)Exactly two fold
C)Just over three fold
D)About four fold
A
D)About four fold
21
Q
Increasing the mAs, the MRT is
A)Making the beam more penetrating
B)Improving the quality of the beam
C)Creating more radiation
D)Creating more scatter
A
C)Creating more radiation
22
Q
In Bremsstrahlung radiation production, the shortest wavelength is produced
A)As the photon approaches the field of the nucleus
B)When the electron is being deviated to the maximum around the nucleus
C)As the electron leaves the full effect of the nuclear field
D)As the photon is at the apex of its turn around the nucleus
A
B)When the electron is being deviated to the maximum around the nucleus
23
Q
Half Value Layer (HVL) is defined as a thickness of attenuator that will
A)Double x-ray quantity
B)Double x-ray quality
C)Half x-ray quality
D)Half x-ray quantity
A
D)Half x-ray quantity
24
Q
At 80 kVp, Bremsstrahlung x-rays produced in a tungsten targeted x-ray tube
A)Are all diagnostically useful
B)Are generally less useful then characteristic x-rays
C)Outnumber characteristic x-rays
D)Are less intense than if produced in a molybdenum target x-ray tube.
A
C)Outnumber characteristic x-rays
25
Characteristic radiation is produced by the
A)Incoming freed cathode electron
B)Ejected shell electron on leaving
C)Inner shell electron moving outwards
D)Outer shell electron moving inwards
D)Outer shell electron moving inwards
26
Ionisation is the
A)Removal of an orbital electron from an atom
B)Addition of an electron to an atoms orbit
C)Movement of an outer shell electron to an inner shell
D)Production of x-radiation
A)Removal of an orbital electron from an atom
27
Which statement is correct?
A)Compton scatter provides useful information on x-ray images
B)Compton scatter only occurs when low energy procedures are taking place
C)Compton electrons are unable to create more Compton events
D)Compton scatter is a source of occupational exposure
D)Compton scatter is a source of occupational exposure
28
When operating an x-ray system at 80 kVp:
A)None of the x-rays produced will have energy of 80 keV
B)The x-rays produced will have a minimum energy of 80 keV
C)The x-rays produced will have a maximum energy of 80 keV
D)All of the x-rays produced will have energy of 80 keV
C)The x-rays produced will have a maximum energy of 80 keV
29
Why does Classical / Coherent scattering have very little effecton x-ray images?
A)Only very low energy photons are affected
B)Only present in energy levels much higher than obtainable in diagnostic images
C)Classical scattering is diverted away from the IR
D)Classical scattering is not an interaction or radiation
A)Only very low energy photons are affected
30
Compton scatter with a scattering angle (θ) of 180° is called
A)Back scatter
B)Forwards scatter
C)Pair production
D)Photoelectric effect
A)Back scatter
31
How does a broad focal spot increase geometric unsharpness on a radiographic image?
A)Reduces penumbra
B)Increase penumbra
C)Increases the occurrence of scatter radiation
D)Decreases the occurrence of scatter radiation
B)Increase penumbra
32
In terms of radiation production, the term binding energy is defined as the energy required to
A)Remove an electron from a particular valence band or orbit
B)Bind two electrons together during interaction
C)Bind two atoms of tungsten together at the anode
D)Heat the cathode inside the x-ray tube
A)Remove an electron from a particular valence band or orbit
33
In this graph, which form of the following exposure factors has been manipulated?
```
A)kVp
B)mAs
C)Filtration
D)SID
Xray tube powerpoint question 34 for diagram
```
B)mAs
34
If a material is absorbing radiation exponentially at 10% per unit thickness, the radiation intensity would decrease in the sequence:
A)100%, 91%, 82.5%, 76%, 63.3%
B)100%, 90%, 80%, 70%, 60%
C)100%, 90%, 81%, 73%, 65%
D)100%, 81%, 64%, 49.5%, 36.7%
C)100%, 90%, 81%, 73%, 65%
35
In this graph, which from the following exposure factors has been manipulated?
A)kVp
B)mAs
C)Filtration
D)SID
refer to xray tube powerpoint question number 36 for diagram
A)kVp
36
At quidditch practice, Katie Bell has a mid air collision and is brought in for lumbar spine x-rays to rule out vertebra fractures. The appearance of the AP radiograph you produce is very white and you are unable to see cortical outline through the lumbar region. Which from the following should you do to ensure that the repeated AP image is of diagnostic quality?
A)Increase kVp by 15%
B)Double mAs
C)Increase the SID
D)Half the mAs
A)Increase kVp by 15%
37
A few days later, Katie presents again to the x-ray department, this time for a pelvis x-ray as she is having left hip pain when weight bearing. The exposure factors you use for your AP Pelvis are 75 kVp, 1,000 mm SID and 16 mAs. When you process the AP projection you find that there is a fair amount of quantum mottle in your radiograph and the EI is 1287. Which from the following should you do to ensure that the repeated AP image is of diagnostic quality?
A)Reduce kVp by 15%
B)Double mAs
C)Increase the SID to 1200 mm
D)Half the mAs
B)Double mAs
38
If the recommended manual mAs exposure for a chest radiograph on a five (5) year old child is 3.2mAs, then this can be achieved by using which from the following exposures?
A)100 mA, 0.32 seconds
B)200 mA, 0.016 seconds
C)400 mA, 0.08 seconds
D)400 mA, 0.8 seconds
B)200 mA, 0.016 seconds
39
In order for an x-ray tube to produce x-rays there are three essential things that MUST happen. What is NOT one of those essential three things?
A)There must be a potential difference between cathode and anode
B)The anode must be positive in respect to the cathode
C)The cathode must be emitting electrons
D)The anode must be rotating
D)The anode must be rotating
40
Earlier we said that 97 – 99% of the energy used in the production of x-rays is converted into heat. What is NOT a way that heat is dissipated?
A)Conduction
B)Transmission
C)Convection
D)Radiation
B)Transmission
41
Give two advantages and two disadvantages of rotating anodes:
ADVANTAGES
1. Can use higher kVp, mAs, time, greater thermal load
2. Faster repetition rate,
DISADANTAGES
Cost
2. Bearing wear out, less robust – mechanical stress
42
Complete the following paragraph by putting the following words into the correct order
Anodes made from __are prone to ____and _ due to the continual _ and _, and the mechanical stresses due to rotation.Alloy materials are structurally stronger
Anodes are normally made from an alloy which is a blend of tungsten and rhenium which is more resitant to cracking and pitting.
Anodes made from __pure tungsten_ are prone to _pitting and cracking_ due to the continual heating_ and cooling_, and the mechanical stresses due to rotation.Alloy materials are structurally stronger
Anodes are normally made from an alloy which is a blend of tungsten and rhenium which is more resitant to cracking and pitting.
43
Rotating anode discs are often laminated using graphite, tungsten and molybdenum. Label the diagram.
refer to xray tube powepoint question 44 for diagram
A Tungsten
B Molybdenum
C Graphite
44
The ideal anode angle for a rotating anode from vertical is?
A)0° - 3°
B)7° - 10°
C)17° - 20°
D)27° - 30°
C)17° - 20°
45
A rotating anode is turned by ______ coils which induce a field into the _____ within the insert.
A)Rotor, Stator
B)Spindle, Stem
C)Stem, Spindle
D)Stator, Rotor
D)Stator, Rotor
46
Direct Current (DC) produces the rotating magnetic field that causes the anode to rotate?
TRUE
FALSE
FALSE
47
Explain the term ANODE HEEL EFFECT using this diagram
| refer to xray tube powepoint to see
Intensity of the x-ray beam on the anode side of the x-ray field is reduced due to attenuation. This can be used to the MRT’s advantage when x-raying body parts of different thickness. eg T-spine
48
What is this an image of?
| refer to xray tube powerpoint to see picture question number 49
A dual filament cathode
49
Generally what is the upper limit mA for a fine focus exposure?
A)100 mA
B)200 mA
C)400 mA
D)500 mA
B)200 mA
50
Generally what is the upper limit mA for a fine focus exposure?
A)100 mA
B)200 mA
C)400 mA
D)500 mA
B)200 mA
51
Using this rating chart, explain why a desired exposure of 80 kVp,400 mA for 0.1 second is an unsafe exposure yet the same amount o fx-rays produced using 80 kVp and 200 mA would be a safe exposure.
refer to powerpoint tube ratings question 1 to see diagram
the point intersecting is above the 400 mA line for the 80kVp, for 0.1 seconds there for this exposure is said to be unsafe as any point intersecting above the line and to the right are unsafe.
the point intersecting is below the 200 mA line for 80 kVp at 0.1 seconds there for this exposure is said to be safe as any point intersecting under the mA line is said to be safe/
52
You perform two x-rays, one directlyafter the other. The first exposureis 150,000 HU and the second is 100,000 HU.
How many minutes will it take for theanode to cool to only 50,000 HU?
refer to graph question 2 tube ratings
1.5 mins
53
Using this rating chart. Which fromthe following would be a safeexposure?.
```
A)70 Kvp, 500 mA, 0.1 seconds
B)80 kVp, 300 mA, 0.04 seconds
C)110 kVp, 400 mA, 0.1 seconds
D)90 kVp, 400 mA, 0.04 seconds
refer to tube rating powerpoint question 4
```
B)80 kVp, 300 mA, 0.04 seconds
54
Using this rating chart. Which fromthe following would be an unsafeexposure?.
```
A)70 kVp, 200 mA, 0.2 seconds
B)60 kVp, 400 mA, 0.2 seconds
C)90 kVp, 100 mA, 0.2 seconds
D)120 kVp, 200 mA, 0.2 seconds
refer to tube rating power point question 5
```
A)70 kVp, 200 mA, 0.2 seconds
55
If the first exposure of the day was to heat the anode to 350,000 HU, how long would it take for it to cool down completely?
refer to tube ratings powerpoint question 6
14 minutes
56
```
If the first exposure of the day was to heat the anode to 250,000 HU, whatis the minimum time period that it will need to cool for, before you canmake a second exposure of250,000 HU?
A) 1 minute
B)2 minutes
C) 3 minutes
D)6 minutes
```
refer to powerpoint tube ratings question 7
A) 1 minute
57
```
If the first exposure of the day was to heat the anode to 250,000 HU, whatis the minimum time period that it will need to cool for, before you canmake a second exposure of250,000 HU?
A) 1 minute
B)2 minutes
C) 3 minutes
D)6 minutes
```
refer to powerpoint tube ratings question 7
A) 1 minute
58
Raising the kVp
A)Increase the size of the electrons
B)Decreases the wavelengths in the beam
C)Increases the quantity of photons reaching the anode
D)Decreases quantum mottle in the image
B)Decreases the wavelengths in the beam
59
What piece of equipment may an MRT choose to use to even out the differences in thickness of the foot when performing a radiographic examination?
A)Filter
B)Grid
C)Sandbag
D)Sponge
A)Filter
60
The greater the potential difference across the cathode to anode
A)The greater the wavelength of the beam of radiation
B)The smaller wavelength of the beam of radiation
C)Greater collimation is required
D)Greater absorption can be expected
B)The smaller wavelength of the beam of radiation
61
If a material is absorbing radiation exponentially at 10% per unit thickness, the radiation intensity would decrease in the sequence
A)100%, 91%, 82.5%, 76%, 63.3%
B)100%, 90%, 80%, 70%, 60%
C)100%, 90%, 81%, 73%, 65%
D)100%, 81%, 64%, 49.5%, 36.76%
C)100%, 90%, 81%, 73%, 65%
62
Half Value Layer (HVL) is defined as a thickness of attenuator that will
A)Double x-ray quantity
B)Double x-ray quality
C)Half x-ray quality
D)Half x-ray quantity
D)Half x-ray quantity
63
The effectiveness of a filter is related to its
A)Lead equivalence
B)Aluminium equivalence
C)Tissue equivalence
D)Absorption equivalence
B)Aluminium equivalence
64
Which of the following statements is correct?
A)Using a filter cuts out the short wavelength x-rays completely
B)Increasing the mA also increases the shortest wavelength x-rays
C)Increasing the kVp increases the wavelength of the most intense x-rays
D)Using a filter reduces the number of longer wavelengths in the x-ray beam
D)Using a filter reduces the number of longer wavelengths in the x-ray beam
65
Which of the following is NOT a type of filtration used in x-ray production?
A)Additional
B)Compensatory
C)Inherent
D)Linear
D)Linear
66
What is inherent filtration?
A)A filter applied by an MRT to even out difference thickness of body tissue
B)An additional filter fitted to the x-ray machine to remove low energy x-rays
C)Photons from the useful beam
D)The filtration of the useful beam that takes place due to the permanent components of the x-ray tube
d) The filtration of the useful beam that takes place due to the permanent components of the x-ray tube
67
What is NOT a reason for the use of aluminium as a filter? It:
A)hardens the beam
B)is cheap and readily available
C)is efficient in removing low energy x-rays through photoelectric effect
D)removes all the high energy x-rays leaving only the low energy x-rays
d) Removes all the high energy x-rays leaving only the low energy x-rays
68
With age, inherent filtration tends to increase. Why?
A)Tungsten vaporises and is deposited inside the glass insert
B)As aluminium ages, it gets denser stopping more x-rays
C)There are only so many electrons that can be generated in the lifetime of the filament
D)The repeated heating and cooling of the oil makes it thicker, stopping more x-rays
a) Tungsten vaporises and is deposited inside the glass insert
69
The removable type of filters designed to selectively change the intensity of the x-ray beam and change the appearance on the image are called?
A)Inherent
B)Additional
C)Compensatory
D)Aluminium equivalence
c) Compensatory
70
Complete the sentence by deleting the incorrect words
Increasing filtration DECREASES / INCREASES the QUALITY / QUANTITY of the x-ray beam.
Increasing filtration INCREASES the QUALITY of the x-ray beam
71
What is the benefit to the patient of ‘hardening the beam’?
Hardening the beam reduces scatter and reduces the patient dose
72
```
Name at least four (4) materials that COMPENSATORY filters may be composed from?
1
2
3
4
```
1. Aluminium
2. Copper
3. Acrylics
4. Tin
73
The number of lead panels that open and close in a single leaf collimator is:
A)1
B)2
C)4
D)8
C)4
74
Which from the following list is NOT a purpose / function of a collimator?
A)Define the size and shape of the x-ray beam
B)Increase the energy of the beam so that it is more penetrating
C)Reduce the effect of off-focus radiation
D)Improve image resolution by reducing the production of scatter radiation
B)Increase the energy of the beam so that it is more penetrating
75
Which is NOT a type of collimator?
A)Single leaf
B)Multi leaf
C)Two tiered
D)Diaphragm
C)Two tiered
76
Which of the following would an MRT be likely to alter first in order to prevent the production of scatter?
A)Reduce the kVp range
B)Reduce the amount of additional filtration
C)Reduce the body part thickness
D)Reduce the size of the collimated field
D)Reduce the size of the collimated field
77
Complete the sentence:
A single leaf collimator has a _ _ _ _ _ _ set of _ _ _ _ leaves that work together as _ _ _ _ _ _ _ / _ _ _ _ _ .
Pick from the following words:
```
OPPOSED
SINGLE
PAIRS
FOUR
DOUBLE
```
A single leaf collimator has a SINGLE set of FOUR leaves that work together as OPPOSED/PAIRS
78
Off-focus radiation is classified as scatter radiation.
TRUE
FALSE
FALSE
79
Unjumble the following word the relates to Collimators:
| R E C Y D L I N
cylinder
80
Unjumble the following word the relates to Collimators:
| RSITE
TIERS
81
If you increased your collimated field from 20 x 20 cms to 25 x 25 cms, what is the percentage increase between collimated area 1 and collimated area 2?
A)20%
B)25%
C)56%
D)70%
A)20%
82
This picture is of a ________ type of collimator.
```
A)Single leaf
B)Multi leaf
C)Positive beam Limitation
D)Fixed shape or diaphragm
refer to collimators diaphragm... question 11
```
D)Fixed shape or diaphragm
83
What does a collimator NOT do?
A)Define the size and shape of the x-ray beam emerging from the tube port.
B)Minimises the area being irradiated and spares adjacent tissue from unnecessary exposure.
C)Increases the penetration ability of the x-ray beam
D)Leads to reduced scatter radiation, improving contrast resolution.
C)Increases the penetration ability of the x-ray beam
84
If you were to increase from green collimation area 27cm x 18cm to the larger 32cm x 22cm,what is the increase in he collimation
Calculate (showing workings) how much larger the 32 x 32 area is when compared to the smaller 27 x 22 area
18cm bigger
85
Where would you NOT find a fixed shape or diaphragm collimator?
A)Dental Unit
B)Cranial Unit
C)Fluoroscopy Unit
D)OPG
C)Fluoroscopy Unit
86
What category of collimators does the one in the following picture fall in to?
A)Single leaf
B)Multiple leaf
C)Two tiered
D)Diaphragm
refer to collimator powerpoint question 15
D)Diaphragm
87
Which is NOT a type of collimator?
A)Multi leaf
B)Two tiered
C)Diaphragm
D)Single
B)Two tiered
88
Explain in a sentence what the term Positive Beam Limitation means.
senses in the bucky tray to detect the size of the IR to send an electronic signal that will adjust the leaves / shutters and automatically collimate to the size of the IR (and no larger).
89
The collimators on a fluoroscopy unit are generally motor driven. So what statement is true?
A)You can not adjust collimators to a field of view (FOV) larger than the size of the II.
B)You can not adjust collimators to a FOV smaller than the size of the II.
C)You can not adjust the vertical collimators to a FOV smaller than the size of the II.
D)You can not adjust the horizontal collimators to a FOV smaller than the size of the II
A)You can not adjust collimators to a field of view (FOV) larger than the size of the II.
90
Explain the term Off Focus Radiation and then the importance of collimation in reducing the impact of off focus
During an exposure some projectile electrons are directed away from the anode target track and can strike other portions of the anode or tube contents.
Low energy x-rays can be produced from the likes of the glass insert and the cathode assembly.
91
When using a focus grid:
A)The stripe should be face down against the IR
B)The grid must be used at a set distance
C)An extremity IR should be used
D)The grid can be angled in any direction
a) The stripe should be face down
92
Larger body parts create more interactions between x-rays and tissue, so more secondary radiation is created. What piece of equipment do MRTs use to reduce this reaching the IR?
A)A grid
B)A compensatory filter
C)An extremity IR
D)Lead to cover the patient’s gonads
a) A grid
93
The term grid ratio relates to:
A)The ratio of the number of grid lines per centimetre to the width of the grid.
B)The relationship between the thickness of the lead strips to the height of the interspace.
C)The relationship between the width of the interspace to it’s height.
D)The focal range of a focused grid to the SID use.
c) The relationship between the width of the interspace to its height
94
A secondary radiation grid is made up of hundreds of strips of ________ layered together with hundreds of strips of a radiolucent interspace material.
A)Plastic
B)Lead
C)Copper
D)Tungsten
b) Lead
95
What is the primary function of a grid?
A)To enable the MRT to use high exposures without harming the patient.
B)To reduce scatter reaching the IR and degrading the image.
C)To even out tissue densities on the resulting image
D)To ensure that the lead protection on the patient is effective.
b) To reduce the scatter reaching the IR and degrading the image
96
Which of the following exposure factor manipulations DO NOT need to be considered when changing from a non-grid to a focus grid exposure?
A)SID
B)mAs
C)Focal spot size
D)kVp
Focal spot size
97
The type of grid which has tapered edges to lessen the impact of grid cut off is a:
A)Parallel grid
B)Prismatic grid
C)Crosscut grid
D)Focussed grid
Prismatic grid
98
Which was the most successful type of movement used in Bucky mechanisms in older x-ray machines to remove the appearance of grid lines from the radiograph?
A)Oscillating
B)Reciprocating
C)Variable motion
D)Single stroke
reciprocating
99
The ideal material to construct the interspaces in a grid for use in digital radiography (DR) would be ___________________ .
However this would make the grid impossible to manufacture. Therefore the next best substitute to construct the interspaces in a grid for use in DR is __________________ .
Air,
| aluminium
100
What is the equation to work out grid ratio?
Grid ratio = H/D
| Height of the strips/ Width of the interspace
101
The term Grid Factor indicates
A)The distance a grid must be used at
B)The amount the kVp must be increased by
C)The percentage efficiency of the grid in absorbing scattered radiation
D)The amount the mAs must be increased by
d) The amount the mAs must be increase by
102
Would can help reduce the secondary radiation reaching the IR?
A)Increasing the SID
B)Reducing the SID
C)Increasing the SOD
D)Increasing the OID
Increasing OID
103
Which of the following may still occur when correctly using a parallel grid?
A)Grid cut off may occur in the centre of the image
B)Grid cut off may occur at the very edges of the image
C)Quantum mottle may be caused in the region of interest
D)Grid cut off may occur throughout the entire image.
B)Grid cut off may occur at the very edges of the image
104
Which of the following is not a type of timer used to terminate an exposure?
Additional timer
Dead mans switch
An interlock
Guard timer
Dead mans switch
