Rad Phys Exam 2 Flashcards
Of the choices below, which is true about a reciprocating grid?
it requires a 10:1 ratio
it requires 103 lines per inch
it is thicker than a stationary grid
it requires a faster exposure time
it is less expensive than a stationary grid
it is thicker than a stationary grid
To double density of a film by using mAs, What would you do?
increase the mAs by 100%
When converting from a grid with a low ratio to a grid with a high ratio which of the following would be the best to do to maintain good film quality?
increase the mAs
Which of the following is recommended for spinal radiography in the usual chiropractic office?
a focus grid
which of the following effects does using a high kV technique have?
produces more scatter
The preferred focused grid range for spinal radiography is ____
40” to 72”
If a film has an overall darkened gray appearance but visible structures the probable cause of the problem would be which of the following?
exposure of the film to scatter
The term “optimal kV” refers to which of the following?
the lowest possible mAs with acceptable contrast on the film
How many lines per inch are recommended for a stationary grid?
100-103
Diminished penetration at the periphery of a grid is termed _____ _________
Grid cut-off
If a film is said to be “burned out” what would it look like?
Too dark
Which choice below is the main reason why a “fixed kV technique is preferred?”
Contrast is consistent
Remnant radiation refers to which of the following?
Scattered rays that leave the patient and reach the grid and primary rays that leave the patient and reach the grid
Which of the following would produce the least amount of grid lines?
a moving grid
Exceeding the optimal kV range while maintaining good density will yield a film that has which of the following?
a long scale contrast
As a general rule, if you are going to x-ray an elderly patient you should do which of the following to your established radiographic technique?
decrease it
Which of the following would increase patient exposure?
- using a high kV technique
- using a 10:1 stationary grid
- using a high speed screen
- using an air gap technique
using a 10:1 stationary grid
If you took a lateral cervical x-ray with 66kV at 100 mAs for 1/10 of a second at 72” FFD and it was too light but you see the structures, which of the following would be the best solution for your retake?
increase the kV by 15% (optimal kV cervical spine 75-85 kV)
About how much increase in mAs is required when going from a non grid technique to suing a technique with a 12:1 grid?
5 times
If you took a 14x17” lateral lumbar and saw that the L5-S1 area was too light, which of the following would be the best thing to do?
take a spot 8x10” lateral, increase the mAs by 60% and increase the kV
If you saw a blood vessel on end (axially) on a chest film it would probably look like which of the four natural body (subject) densities?
water
if you saw 2 structures each with paralleling tracks of calcification overlying the articular pillars diverging at the superior and closer at the inferior at what would you be looking?
part of the thyroid cartilage
If you took an A-P lumbar on a thin patient using 85kV at 100mA with the exposure time of 1/2 second and the film demonstrated all of the structures but was too light which should you do to get a better film?
increase the mAs by doubling it
Of the choices below which is true about a reciprocating grid?
- it requires a 10:1 ratio
- it requires 103 lines per inch
- it is thicker than a stationary grid
- it requires a faster exposure time
- it is less expensive than a stationary grid
it is thicker than a stationary grid
The term “optimal kV” refers to which of the following?
the lowest possible mAs with acceptable contrast on the film
Which of the following is recommended for spinal radiography in the usual chiropractic office?
a focused grid
Which of the following effects does using a high kV technique have?
produces more scatter
The preferred focused grid range for spinal radiography?
40” to 72”
If a film has an overall gray appearance but visible structures the probably cause of the problem would be which of the following?
exposure of the film to scatter
Diminished penetration at the periphery of a grid is termed ____ ________
grid cut off
To double the density of a film by using mAs, what would you do?
increase the mAs by 100%
How many lines per inch are recommended for a stationary grid?
100-103
When converting a grid with a low ratio to a grid with a high ratio which of the following would be the best to do to maintain good film quality?
increase the mAs
If a film is said to the “burned out: what would it look like?
too dark
Which choice below is the main reason why a “fixed kV” technique is preferred?
contrast is consistent
Which of the following would produce the least amount of grid lines?
A moving grid
Exceeding the optimal kV range while maintaining good density will yield a film that has which of the following?
A long scale contrast
Remnant radiation refers to which of the following?
scattered rays that leave the patient and reach the grid and primary rays that leave the patient and reach the grid
As a general rule, if you are going to x-ray an elderly patient you should do which of the following to your established radiographic technique?
decrease it
Which of the following would increase patient exposure?
using a high kV technique
If you took a lateral cervical with 66kV at 100mA for 1/10 of a second at 72” FFD and it was too light but you could see the structures, which of the following would be the best solution for your retake?
increase the kV by 15%
About how much increase in mAs is required when going from a non grid technique using a technique with a 12:1 grid?
5 times
If you took an A-P lumbar on a thin patient using 85kV at 100 mA with the exposure time of 1/2 of a second and the film demonstrated all of the structures but was too light which you should do to get a better film?
increase the mAs by doubling it
If you took a lateral 14x17” lateral lumbar film and saw that the L5-S1 area was too light, which of the following would be the best thing to do?
take a spot 8x10” lateral, increase the mAs by 60% and increase the kV
If you saw 2 structures each with paralleling tracks of calcification overlying the articular pillars diverging at the superior and closer at the inferior at what would you be looking?
part of the thyroid cartilage
If you took four A-P lumbar films, the first with 95kV and 6.25mAs, the second with 106kV and 3.75mAs, the third at 58kV and 60.0mAs and the fourth at 85kV and 8.0mAs, which would have the lowest contrast?
the second
If you decided no to use a grid for an AP lumbar film and adjusted the radiographic technique to maintain a good density what would be the outcome?
the film would be very gray
To double the density of a film with kVp, you should apply which rule>
15% rule
If you compared 2 radiographs of a cervical spine with one having been taken at 40” and the other at 72” with the appropriate change in the radiographic technique, what would you find?
on the 72” film the image will be smaller and clearer
Which of the following could be a problem if your x-ray tube was laterally shifted from the center of the film?
shape distortion
What is the primary purpose of a grid?
to reduce scatter radiation to the film
Which of the following increases Compton’s Radiation?
higher kVp (higher kVp=more scatter)
What is the term used when comparing the height of the absorbing strips to the width of the interspacing material of a grid?
grid ratio
Which is the recommended optimal kV range for an A-P lumbar film?
80-90
When shopping for a grid which interspacing material would you want because it’s best for x-raying the spine?
aluminum
Which of the following best describes back scatter?
scatter that is directed toward the tube
If you wanted to alter your contrast so that a radiograph had more gray tones, what would you increase?
kV
Which effect does using a reciprocating grid have that a stationary grid doesn’t?
it blurs out grid lines
If you took a lateral cervical with 66kV at 100mA for 1/10 of a second at 72” FFD and was too light but you could see the structures, which of the following would be the best solution for your retake?
increase the kV by 15%
Of the following, which would produce a film with the most visible grainy?
a high kVp/low mAs film
If you too four lateral cervical films using 75kV with 14mAs for the first, 65kV with 14mAs for the second, 85kV with 14mAs for the third, and 95kV with 14mAs for the fourth, which would be the darkest?
the fourth
How much increase in mAs is needed to maintain the same density when reducing the x-ray field from 14x17” to 8x10”?
60%
Which is not true about an x-ray beam?
the more peripheral parts of the beam causes less distortion
What is true about an x-ray beam?
- exposure to it will cause x-ray film to darken
- the greater its intensity the more penetrating it is
- its intensity lessens as the distance increases from the sources
Which is the recommended optimal kV range for a A-P full spine?
80-100
A film exposed to secondary radiation will have which of the following appearances?
it grays the film making it dark
Which would be most likely to decrease the amount of scattered radiation to a film?**
an increase in mAs
when x-raying an elderly obese patient, which of the following would be helpful in obtaining the best quality film?
using a lower kV in the optimal range
Of the following which would cause a decrease in subject density?
- disuse atrophy
- Paget’s disease
- sclerotic osteosarcoma
- fluid in the lung
disuse atrophy
If you increased the mAs and reduced the kV from a given radiographic technique what would be the outcome?
it would have more contrast
To decrease the density of a previously taken film by 1/2, which would you do?
decrease the mAs by 50%
If the film is too dark, it is said to be _____
overexposed
Determine which radiographic technique would have the shortest scale of contrast
- 60kV with 100mA for 2 sec
- 70kV with 300mA for 1/2 sec
- 80kV with 50mA for 2 sec
- 90kV with 200mA for 1/4 sec
60kV with 100mA for 2 seconds
About how many kV would be needed to make the slightest visible change in density on a radiograph if you were using a single phase unit?
4
Which effect would adding 100% more mAs to a radiographic technique have?
it would double the density of the film
when x-raying an elderly obese patient, which of the following would be helpful in obtaining the best quality film?
using a lower kV in the optimal range
Which of the following best describes what you should expect if you retake an Ap lumbar with 15% in the kV and leave the mAs constant?
the density of the film would be reduced by 1/2
If you have a radiograph of the lumbar spine that is noticeably too light but you can see the bones on it and if you decided to solve your problem by the 15% rule, which would you do?
- increase the kV by 15%
- decrease the kV by 15%
- increase the mAs by 15%
- decrease the mAs by 15%
Increase the kV by 15% ( not decrease kV because too light, you would have of double the mAs, and if it was too dark cut mass in 1/2)
Which of the following refers to an attenuation of part of the beam by the grid?
grid cut-off
Which is the recommended optimal kV range for an AP thoracic film?
75-85
If you looked into the port of a used x-ray tube and saw that the entire surface of the anode had bumps which of the following terms best matches this appearance?
anode pitting
A filament does what?
forms electrons
In which direction do grid lines run?
in the long axis of the patient
Which radiographic technique would cause the most absorption of x-rays in a patients body?
10mAs with 140kV
What is the most common cause of a blurry image in practice?
patient motion
When using a stationary grid which of the following is recommended for spinal filming?
a 10:1 grid ratio
As a general rule, if you are going to x-ray an elderly patient you should do which of the following to your established radiographic technique?
decrease it
contrast between structures of different subject densities is due to which of the following?
differential absorption
Which of the following exposure techniques would have the lowest contrast?
- 200mAs with 75kV
- 150mAs with 65kV
- 100mAs with 95kV
- 50mAs with 100kV
50mAs with 100kV
Which best describes the effect that scatter radiation has on a film?
it causes a graying of the film
All other factors being equal which radiographic technique would demonstrate the most film grain (quantum mottle)?
- 70kV with 25mA for 1 sec
- 80kV with 50mA for 1/2 sec
- 90kV with 100mA for 1/4 sec
- 100kV with 200mA for 1/8 sec
100kV with 200 mA for 1/8 sec
The ___ _______ is the main function of mAs
film density
When x-raying an obese patient, which of the following would be helpful in obtaining a better quality film?
lower kV in the optimal range
Osteoporosis will usually require you to do which of the following?
reduce the tube output
Which is the recommended optimal kV range for an AP thoracic film?
75-85
If you took a 14x17” lateral lumbar film and saw that the L5-S1 area was too light, which of the following would be the best thing to do?
- Take a spot 8x10” lateral, increase the mAs by 60% and increase the kV
- Not take an 8x10” spot lateral and increase the mAs 60%
not take an 8x10” spot lateral and increase the mAs 60%
Which would be most likely to decrease the amount of secondary radiation to a film?
an increase in the mAs
Which of the following radiographic projections routinely uses an air gap technique?
lateral cervical
A film with a darkened overall gray appearance could be caused by which of the following?
exposure of the film to scatter
About how much increase in mAs is required when going from a non grid technique to using a technique with a 12:1 grid?
5 times
If you wanted to alter your contrast so that a radiograph had more gray tones, what would you increase?
kV
Which of the following refers to an attenuation of part of the beam by the grid?
grid cut-off
If you took four AP lumbar films, the first with 95kV and 6.25mAs, the second with 106 and 3.75mAs, the third at 58kV and 60.0mAs and the fourth at 85kV and 8.0mAs, which would have the lowest scale of contrast?
the second one
If you took a lateral cervical with 66kV at 100mA for 1/10 of a second at 72” FFD was too light but you could see the structures, which of the following would be the best solution for your retake?
increase the kV by 15%
To double the density of a film by using mAs, what would you do?
increase the mAs by 100%
Which of the following would increase patient exposure?
using a 10:1 stationary grid
Which choice below is the main reason why a “fixed kV technique is preferred”?
Contrast is consistent
A film that is lighter on one side than the other most likely would indicate ____ ______
grid cut-off
Which of the following best describes back scatter?
scatter that is directed toward the tube
Which of the following best describes the outcome reducing the mAs by 1/2 keeping the kV and the distance constant?
the film density would be decreased
Of the following which would cause a decrease in subject density?
disuse atrophy
Which of the following could be a problem if your x-ray tube was laterally shifted from the center of the film?
shape distortion
If you tool and AP lumbar on a thin patient using 85kV at 100mA with the exposure time of 1/2 second and the film demonstrated all of the structures but was too light which should you do to get a better film?
increase the mAs by doubling it
To double the density of a film by using kV, what would you do?
increase the kV by 15%
Which of the following would result in an increase in the amount of x-rays passing through patient without an interaction that would produce secondary radiation?
higher kV
Which of the following is recommended for the usual chiropractic office to use?
a focused grid
The height of a grid lead strips compared to the width between them is called what?
grid ratio
Which of the following is recommended for the usual chiropractic office use?
focused grid
Which of the following 3 radiographic projections should routinely use compensating filtration?
AP thoracic, lateral thoracic and full spine
Comparing two films with the kV and mAs constant, one taken at 40” FFD and the other at 72” FFD, which of the following would occur?
increased density of the 40” film and decreased the image size on the 72” film
The 10 day rule refers to which of the following?
10 days after the onset of menses is the safest time for x-raying a female
An accurate collimator should not allow more than ____ percent of the SID of light outside of the exposure field.
4
If a film was taken at 80kV at 100mA for 1/2 second and a second was taken at 80kV at 50mA for one second and a third film at 80kV at 200 mA for 1/4 second, what would be the outcome?
the third film would have less density
Which of the following is the most effective in reducing secondary radiation?
filtration
The height of a grids lead strips compared to the width between them is called what?
grid ratio
Too high of a kV will have which effect on the film?
quantum mottle
Which of the following statements is true about film density?
50% of the mAs is equal to 15% of the kV
Which of the following would increase patient exposure?
using a high speed screen
If you took a lateral lumbar film with 90kV at 100mA for 1/4 of a second using 40” FFD and it was too light but you could see all the structures, which should you do to get a better film?
increase the mA by doubling it
If you took a lateral cervical with 66kV at 100mA for 1/10 of a second at 72” FFD and it was too light but you could see the structures, which of the following would be the best solution for your retake?
increase the kV by 15%
Which of the following could be a problem if your x-ray tube was laterally shifted from the center of the film?
- Magnification distortion
- Shape distortion
Shape distortion (magnification distortion is wrong because this is increased OFD or decrease SID)
Which step should you take when x-raying an elderly female?
- decrease the kV by 15%
- increase the kV by 15%
- decrease the mAs by 30-50%
- increase the mAs by 30-50%
decrease the mAs by 30-50%
Which of the following best describes back scatter?
secondary that reaches the film
Rays that exit the patient and hit the film are termed what?
remnant rays
Which of the following would result in an increase in the amount of x-rays passing through the patient without interaction?
use of a grid
Which choice below is the main reason why a “fixed kV technique is preferred”
contrast is consistent
A film that is a lighter on one side that the other most likely would indicate _____
grid cut-off
A lateral cervical film could use which of the following that a lateral thoracic or lumbar shouldn’t
an air gap
If you took four AP lumbar films, the first with 95kV and 6.25mAs, the second with 106kV and 3.75mAs, the third at 58kV and 60.0mAs and the fourth at 85kV and 8.0mAs, which would have the lowest scale of contrast?
the third
Which of the following three radiographic projections should routinely use compensating filtration?
AP thoracic, lateral thoracic, and full spine
Which of the following is recommended for the usual chiropractic office use?
focused grid
Compensating two films with the kV and mAs constant, one taken at 40” FFD and the other at 72” FFD, which of the following would occur?
increased density of the 40” film and decreased image size on the 72” film
The 10 day rule refers to which of the following?
10 days after the onset of menses is the safest time for x-raying a female
Accurate collimator should not allow more than __ percent of SID of light outside of the exposure field
2
If a film was taken at 80kV at 100mA for 1/2 second and a second was taken at 80kV at 50mA for one second and a third film at 80kV at 200mA for 1/4 second, what would be the outcome?
the third film would have less density
Which of the following is the most effective in reducing secondary radiation?
filtration
The height of a grid’s lead strips compared to the width between them is called what?
grid ratio
Too hight of a kV will have which effect on the film?
quantum mottle
Which of the following statements is true about film density?
50% of the mAs is equal to 15% of the kV
Which of the following would increase patient exposure?
- using a hight kV technique
- using a 10:1 stationary gird
- using a high speed screen
- using an air gap technique
using a 10:1 stationary grid
If you took a lateral lumbar film with 90kV at 100mA for 1/4 of a second using 40” FFD and it was too light but you could see all the structures, which should you do to get a better film?
increase the mA by doubling it
If you took a lateral cervical with 66kV at 100mA for 1/10 of a second at 72” FFD and it was too light but you could see the structures, which of the following would be the best solution for your retake?
increase the kV by 15%
Which of the following could be a problem if your x-ray tube was laterally shifted from the center of the film?
shape distortion
Which step should you take when x-raying an elderly female
decrease the mAs by 30-50%
Which of the following best describes back scatter?
scatter that is directed toward the tube
Rays that exit the patient and hit the film are termed what?
remnant rays
Which of the following best describes the outcome of reducing the mAs by 1/2 and keeping the kV and the distance constant?
the film density would decrease
Of the following which would cause a decrease in subject density?
disuse atrophy
Which of the following could be a problem if your x-ray tube was laterally shifted from the center of the film?
shape distortion
If you took an AP lumbar on a thin patient using 85kV at 100mA with the exposure time of 1/2 second and the film demonstrated all of the structures but was too light which should you do to get a better film?
increase the mAs by doubling it (because 75-85 is optimal kV range)
to double density of a film by using kV, what would you do?
increase the kV by 15%
which of the following would result in an increase in the amount of x-rays passing through a patient without an interaction that would produce secondary radiation?
use of a grid
Which of the following is recommended for the usual chiropractic office use?
A focused grid
The height of grids lead strips compared to the width between them is called what?
grid ratio
If you wanted to alter your contrast so that a radiograph had more gray tones, what would you increase?
kV
Which of the following refers to an attenuation of part of the beam by the grid?
grid cut-off
If you took four AP lumbar films, the first with a 95kV and 6.25mAs, the second with 106kV and 3.75 mAd, the third at 58kV and 60mAs and the fourth at 85kV and 8.0mAs, which would have the lowest scale of contrast?
the second
If you took a lateral cervical with 66kV at 100mA for 1/10 of a second at 72” FFD and it was too light but you could see the structures, which of the following would be the best solution for your retake?
increase the mAs by 15%
To double the density of a film by using mAs, what would you do?
increase the mAs by 100%
Which of the following would increase the patient exposure?
using a 10:1 stationary grid
Which choice below is the main reason why a “fixed kV technique is preferred?”
contrast is consistent
A film that is lighter on one side than the other most likely would indicate ___ ______
grid cut-off
Which of the following best describes back scatter?
scatter that is directed toward the tube
When the image on a film is very gray but the density is good it is said to be __ ___ ______
of low contrast
Which radiographic technique would give the longest scale of contrast?
- 70kV at 50mAs
- 80kV at 25mAs
- 90kV at 15mAs
- 110kV at 7.5mAs
110kV at 7.5mAs
If you wanted to decrease the density of a film, which of the following would best way to do so?
- reduce the time
- reduce the mA
- reduce the kV
- reduce the SID
reduce the time
The term “optimal kV” refers to which of the following?
the lowest possible mAs with acceptable contrast on the film
What would the results be if you increased the kV to accomplish a doubling of the film density and cut the mAs in half?
The film density would remain the same and contrast would decrease
What is undesirable with magnification distortion?
the borders if the object will be blurred
Which of the following would double the number of photons?
going from 100mAs station to a 200mAs station
How would the image appear if there was a patient motion during the exposure?
blurry
Which is not true about an x-ray beam?
the more peripheral parts of the beam causes less distortion
Which of the following is true about increasing kV?
it will increase scatter from the patient
The rays that exit the patient and hit the film are termed what?
remnant rays
Given the following radiographic techniques, which would have the longest scale of contrast?
- 3mAs and 50kVp
- 5mAs and 100kVp
- 10mAs and 75kVp
- 25mAs and 40kVp
5mAs and 100kVp
If you wanted to increase contrast and maintain the same density of a previously taken film, what would you do?
double the mAs and decrease the kV by 15%
Which is the recommended optimal kV range for a lateral thoracic?
85-95
mAs primarily influences which of the following?
density
To decrease the density of a previously taken film by 1/2, which would you do?
- increase the kV by 15%
- decrease the mAs by 50%
- increase mAs by 30%
- decrease the kV by 50%
decrease the mAs by 50%
Which of the following best describes remnant radiation?
rays from the patient that reach the film
Which is preferred for spinal filming?
a fixed kV technique
When using an air gap technique, which of the following usually is NOT needed?
the grid
Of the following, which is preferred grid ratio for spinal filming?
10:1
Which of the following is the most common type of scatter radiation we will produce in our ray’s facility?
compton’s
What would the results be if you increased the kV to accomplish a doubling of the film density and cut the mAs in half?
the film density would remain the same and contrast would decrease
What is the term used when comparing the height of the absorbing strips to the width of the interspacing material of a grid?
grid ratio
When the image on a film is very gray but the density is good it is said to be __ ____ ______
of low contrast
if you took a “14x17” film of a patient’s body part (lets say lumbars) and then for some reason you wanted to take an 8x10” film of the same area with the central ray, kV and mAs the same and both collimated to film size. what would you expect the outcome would be?
the 8x10” would be lighter than the 14” x 17”
If the film is too dark, it is said to be __________
overexposed
When x-raying an elderly obese patient, which of the following would be helpful in obtaining the best quality of film?
- using a shorter tube distance
- using more time and less mA
- using a higher kV in the optimal range
- using a lower kV in the optimal range
using a lower kV in the optimal range
Which is recommended optimal kV range for a AP full spine?
80-100
If you compared the two radiographs of a cervical spine with one having been taken at 40” and the other at 72” with the appropriate change in the radiographic technique, what would you find?
on the 72” film the image will be smaller and clearer
Which of the following will absorb the most x-rays?
bone
Which of the following is most closely related to “differential absorption?”
density
Which of the following is the primary factor for radiographic density?
mAs
With which of the following percentages in mAs would you expect to see the slightest change in radiographic density?
30%
The use of a grid has which main effect on the patient?
it increases x-ray exposure to the patient
The higher the kVp the more ___ radiation is produced?
Compton (scatter)
What is an advantage of high kVp technique?
lowered patient radiation dose
Which of the following would you do if you were going to use the 30% rule?
alter the mAs by 30%
An air gap technique has which effect?
reduces the amount of scatter to the film
When going from a grid to a non-grid technique on the same body part, with the same FFD kVp and mAs would cause which of the following?
the film would be darker
Which of the following is recommended for use of a stationary grid in spinal radiography?
slightly more than 100 lines per inch
