Exam 2: practice questions Flashcards
To double the density of a film by using mAs, what would you do
increase the mAs by 100%
what is true about a reciprocating grid
it is thicker than a stationary grid
when converting from a grid with a low ratio to a grid with a high ratio, what would be the best to maintain good film quality
increase the mAs
what is recommended for spinal radiography in the usual chiropractic office
a focused grid
what effects does using a high kV technique have
produces more scatter
the preferred focused grid range for spinal radiography is
40-72”
if a film has an overall darker gray appearance but visible structures the probable cause of the problem would be what
exposure of the film to scatter
what would absorb the most X-rays in a patient
their vertebra
to decrease the density of a previously taken film by 1/2, what would you do
decrease the mAs by 50%
the ___ is the main function of mAs
film density
what is most closely related to differential absorption
subject contrast
what radiographic projections routinely uses an air gap technique
lateral cervical
if you increased the mAs and reduced the kV from a given radiographic technique, what would be the outcome
it would have more contrast
what best describes the effect that scatter radiation has on a film
it causes a graying of the film
the use of art dark technique can usually be done without what
a grid
what increases Compton’s radiation
higher kVp
what would result in an increase in the amount of X-rays passing through a patient without an interaction with the patient’s atoms
higher kV
what is the closest to what is recommended for spinal filming with a stationary grid
10:1 with 100 lines per inch
what is true about grids
they increase patient radiation
if you compare 2 radiographs of a cervical spine with one having been taken at 40” and the other at 72” with the appropriate change in the rad. tech., what would you find
on the 72” film, the image will be smaller and clearer
what direction do grid lines run
in the long — of the patient
if you wanted a film with more blacks and whites with less gray, what would you do
use a low kV and high mAs
what is the recommended optimal kV range for an A-P thoracic film
75-85
in a Chiro office, what would you think is the most common cause of grid cut-off
the tube being out of alignment
the height of a grid’s lead strips compared to the width between them is called
grid ratio
what refers to an attenuation of part of the beam by the grid
grid cut-off
if you foolishly decide not to use a grid for an AP lumbar film and adjusted the rad. tech. to maintain a good density, what would be the outcome
the film would be very gray
if you wanted to alter your contrast so that a radiograph had more gray tones, what would you have to increase
kV
determine which rad. tech. would yield the longest scale of contrast
95 kV with 10 mAs
to double the density of a film by using mAs, what would you do
increase the mAs by 100%
if you had a film that was over-exposed but you could see the image, what would improve your film
decreasing the mAs 50%
how much increase in mAs is needed to maintain the same density when reducing the X-ray field from 14”x17” to 8”x10”
60%
if you wanted to decrease the density of a film, what would be the best way to do it
reduce the mA
what best describes the outcome of reducing the mAs by 1/2 and keeping the kV and the distance constant
the film density would be decreased
what would produce the same film density as 200 mA for .5 sec
100 mA for 1 sec
if you took a retake and reduced the kVp by 15% and increased the mAs by adding 30%, how would the second film look compared to the first
the second film would be lighter
adding 4 kVp to a rad. tech. with a single phase machine would be equivalent to what
increasing the mAs by 50%
to what does the 15% rule apply
kV
let’s say you took an AP thoracic film with 70kV and 50 mAs and it came out underexposed but you could see all of the structures that you wanted, what would be the best to do
increase the kV by 15%
if you are going to X-ray an elderly patient, you should so what to establish rad tech
decrease it
what is the main reason why a fixed V tech is preferred
contrast is consistent
what could be a problem if your X-ray tube was laterally shifted from the center of the film
shape distortion
what would produce a film with the most visible grain
high kVp/low mAs film
what is undesirable with magnification distortion
the borders of the object will be blurred
what does using a high kV tech have
produces more scatter
the rays that exit the patient and hit the film are termed
remnant rays
what is true about the air-gap tech when normally used in a cervical spine series
it usually doesn’t require the use of a grid
when going from a grid to a non-grid tech on the same body part with the same kVp and mAs, what would be the cause
the film would be darker
to double to the density of a film by using mAs, what would you do
increase it by 100%
what is true about a reciprocating grid
it is thicker than a stationary grid
when converting from a grid with a low ratio to a grid with a high ratio, what would be the best to do to maintain a good film quality
increase the mAs
what is recommended for spinal radiography in the usual Chiro office
a focused grid
what effect does using a high kV tech have
produces more scatter
the preferred focused grid range for spinal radiography is
40” to 72”
if a film has an overall darker gray appearance but visible structures, the probable cause is what
exposure of the film to scatter
the term “optimal kV” refers to what
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
what is the main reason why a fixed kV tech is preferred
contrast is consistent
remnant radiation refers to what
scattered rays that leave the patient and reach the grid and primary rays that leave the patient and reach the grid
what would produce the least amount of grid lines
a focused grid
exceeding the optimal kV range while maintaining good density will yield a film that has
a long scale contrast
if you are going to X-ray an elderly patient, you should do what to establish rad tech
decrease it
what would increase patient exposure
using a 10:1 stationary grid
if you took a lateral cervical with 66 kV at 100 mA for 1/10th of a second at 72” FFD and was too light but you could see the structures, what 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 tech to using a tech with a 12:1 grid
5 times
if you took a 14x17” lateral lumbar film and saw that the L5-S1 area was too light, what would be the best thing to do
take a spot 8”x10” lateral, increase the mAs by 60% and increase the kV
if you saw a blood vessel on end on a chest film, it would probably look like which of the 4 natural body densities
metal
if you saw 2 structures each with paralleling tracks of calcification overlying the articular pillars diverging at the superior and closer at the inferior, what would you be looking at
part of the thyroid cartilage
if you took an AP lumbar on a thin patient using 85 kV 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, what would you do to get a better film
increase the mAs by doubling it
woman: elderly, overweight, retired dancer-> AP lumbar using 90 kV with 100 mAs for 1 second and 40” SID. film is very gray… how do you fix it
use 200 mA and decrease the kV 15%
lateral cervicals at 65 kV and 10 mAs without a grid-> light but you can see the structures… how do you fix it
increase the kV by 15%
what refers to an attenuation of part of the beam by the grid
grid cut off
when using a stationary grid, what is recommended for spinal filming
a 10:1 grid ratio
the use of a grid has what main effect on the patient
it reduces the X-ray exposure to the patient
the preferred focused grid range for spinal rad is
40” to 72”
if a film is too dark but you can still see structures, what is the probable cause of the problem
exposure of the film to scatter
when converting from a grid with a low ratio to a grid with a high ratio-> best option to maintain good film quality
increase the mAs
the higher the kVp, the more ___ radiation is produced
compton (scatter)
what is the most common cause of a blurry image in practice
patient motion
what is the main reason why a fixed kV tech is preferred
contrast is consistent
what is the recommended optimal kV range for an AP thoracic film
75-85
what exposure techs would have the lowest contrast
50 mAs with 110 kV
what is preferred for spinal filming
a fixed kV tech
what is an advantage of thigh kVp tech
lowered patient radiation dose
if you increase the mAs and reduce the kV from a given rad tech, what would be the outcome
it would have more contrast
what best describes what you should expect if you retake an AP lumbar film with 15% decrease in the kV and leave the mAs constant
the density of the film would be reduced by 1/2
what would you do if you were going to use the 30% rule
alter the mAs by 30%
if you were re-xraying an obese pt because you first film was too light but you could see the structures, what would be the best thing to do in order to get the best quality radiograph
increase the mAs
if a film was taken at 80 kV at 100 mA for .5 sec and a second was taken at 80 kV at 5 mA for one second and a third film at 80 kV at 200 mA for 1/4th second, what would be the outcome
they would all be the same
you take a film and it is too light. you want to retake it and double the density by using kVp. how would you do it
increase the kV by 15%
which effect would adding 100% more mAs to a rad tech have
it would double the density of the film
what would absorb most xrays in a pt
their vertebra
exceeding the optimal kV rand while maintaining good density will yield a film that has
a long scale contrast
what is most closely related to differential absorption
subject contrast
thoracic films-> AP measurement is 29 cm-> what would be essential to use
a high frequency unit
what is true about a reciprocating grid
it is thicker than a stationary grid
the term optimal kV refers to what
the lowest possible mAs with acceptable contrast on the film
what is recommended for spinal radiography in the usual chiro office
focused grid
what effect 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
exposure of the film to scatter
diminished penetration at a periphery of a grid is termed
grid cut-off
to double the density of a film 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 from a grid with a low ratio to a grid with a high ratio, what would be the best to do to maintain good film quality
increase the mAs
if a film is said to be burned out, what would it look like
too dark
what is the main reason why a fixed kV tech is preferred
contrast is consistent
what would produce the least amount of grid lines
a moving grid
exceeding the optimal kV range while maintaining a good density will yield a film that has what
a long scale contrast
remnant radiation refers to
scattered rays that leave the pt and reach the grid and primary rays that leave the pt and reach the grid
if you are going to X-ray an elderly pt, you should do what to establish rad tech
decrease it
what would increase pt exposure
using a 10:1 stationary grid
if you took a lateral cervical with 66 kV at 100 mA for 1/10th of a second at 72” FFD and was too light but you could see the structures, what 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 tech to using a tech with a 12:1 grid
5 times
if you took an Ap lumbar on a thin pt using 85 kV at 10 mA with the exposure time of 1/2 of a second and the film demonstrated all of the structures but was too light, what would make it bettwe
increase the mAs by doubling it
if you took a 14x17” lateral lumbar film and saw that the L5-S1 area was too light, what 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 on a chest film, it would probably look like which of the 4 natural body densities
metal
2 structures with paralleling tracks of calcification overlying the articular pillars diverging at the superior and closer at the inferior, what would you be looking at
part of the thyroid cartilage
if you took 4 AP lumbar films, the first with 95 kV and 6.25 mAs, the second with – kV and 3.75 mAs, the third at 58 kV and 60 mAs and the fourth at 85 kV and 8 mAs, which would have the lowest contrast
the second
if you decided not to use a grid for an AP lumbar film and adjusted the rad tech 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 what rule
15%
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 rad tech, what would you find
on the 72” film the image will be smaller and clearer
what 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 shatter radiation to the film
what increases Compton’s radiation
higher kVp
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
what is the recommended optimal kV range for an AP lumbar film
80-90
when shopping for a grid, which interspacing material would you want because it’s best for xraying the spine
aluminum
what 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
what effect does using a reciprocating grid have that a stationary grid doesn’t
it blurs out grid lines
what would produce a film with the most visible grainy
a high kVp/low mAs film
how much increase in mAs is needed to maintain the same density when reducing the X-ray field from 14x17” to 8x10”
60%
what is not true about an X-ray beam
the more peripheral parts of the beam causes less distortion
what is the recommended optimal kV range for an AP full spine
80-100
a film exposed to secondary radiation will have what appearance
it grays the film, making it dark
what would be most likely to decrease the amount of scattered radiation to a film
an increase in the mAs
when xraying an elderly obese pt, what would be helpful in obtaining the best quality film
using a lower kV in the optimal range
what would cause a decrease in subject density
diffuse atrophy
why don’t you want a focused grid with a focal range of 40 to 72”, 8:1 ratio, aluminum interspacing material
the maximum recommended kV for an 8:1 grid is 90 and you might want to se more
Mr. Schylack’s AP measurement in the lumbar region is 40 cm-> age and large abdomen-> what is the predictable problem that you are going to have with the film
there will be too long of a scale of contrast
if you increased the mAs and reduced the kV from a given rad tech, what would be the outcome
it would have more contrast
to decrease the density of a previously taken film by 1/2, what would you do
decrease the mAs by 50%
if a film is too dark, it is said to be
overexposed
determine which rad tech would have the shortest scale of contrast
60 kV with 100 mA for 2 sec
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
what effect would adding 100% more mAs to a rad tech have
it would double the density of the film
what best describes what you should expect if you retake an AP lumbar with 15% decrease 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 decide to solve your problem with the 15% rule, what would you do
increase the kV by 15%
what is the recommended optimal kV range for an AP thoracic film
75-85
what refers to an attenuation of part of the beam by the grid
grid cut-off
if you looked into the port of a used X-ray tube and saw that the entire surface of the anode had bumps, what term would match this appearance
anode pitting
what does a filament do
forms electrons
in which direction do grid lines run
in the long axis of the pt
what rad tech would cause the most absorption of xrays in a pt’s body
10 mAs with 140 kV
what is the most common cause of a blurry image in practice
patient motion
contrast between structures of different subject densities is due to what
differential absorption
what exposure tech would have the lowest contrast
50 mAs with 110 kV
what best describes the effect that scatter radiation has on a film
it causes a graying of the film
the __ is the main function of mAs
film density
osteoporosis will usually require you to do what
reduce the tube output
if you took a 14x17 lateral lumbar and saw that the L5-S1 area was too light, what would be the best thing to do
take a spot 8x10 lateral, increase the mAs by 60% and increase the kV
what would be most likely to decrease the amount of secondary radiation to a film
an increase in the mAs
what rad projections routinely uses an air gap tech
lateral cervical
if you wanted to alter your contrast so that a radiograph had more gray tones, what would you increase
kV
to double the density of a film by using mAs, what would you do
increase the mAs by 100%
