Part 1 Flashcards
1
Q
To double the density of a film by using mAs, what would you do?
A
increase the mAs by 100%
2
Q
Of the choices below, which is true about a reciprocating grid?
A
it is thicker than a stationary grid, more expensive than a stationary grid, too slow for fast exposures
3
Q
Of the choices below, which is true about a stationary grid?
A
requires a 10:1 ratio and 103 lines per inch
4
Q
When converting from a grid with low ratio to a grid with high ratio, which would be the best to maintain the good film quality?
A
increase the mAs (could also increase kV, but mAs produces less scatter)
5
Q
Which of the following is recommended for spinal radiography in the usual chiropractic office?
A
focused grid
6
Q
What are the types of stationary grids?
A
focused, parallel
7
Q
Which grid is NOT practical for spinal films?
A
crossed grid
8
Q
Which of the following effects does using a high kV technique have?
A
produces more scatter, more penetration, less absorption
9
Q
The preferred focused grid range for spinal radiography is…?
A
40”-72”
10
Q
If a film has an overall darkened grey appearance, but visible structures, the probable problem would be which of the following?
A
exposure of the film to scatter, too high kV technique
11
Q
The term “optimal kV” refers to which of the following?
A
the lowest possible mAs with acceptable contrast on the film
12
Q
How many lines per inch are recommended for a stationary grid?
A
100-103
13
Q
Diminished penetration at the periphery of a grid is what term?
A
grid cut off
14
Q
Define focal range.
A
variable FFDs that will be acceptable
15
Q
Define grid ratio.
A
height of strips to width of interspacing
16
Q
Define grid radius?
A
angle of strips that match the divergence
17
Q
If a film is said to be “burned out”, what would it look like?
A
too dark
18
Q
Which choice below is the main reason why a “fixed kV technique” is preferred?
A
the contrast is consistent
19
Q
Remnant radiation refers to which of the following?
A
scattered/primary rays that leave the patient and reach the grid
20
Q
Which of the following would produce the least amount of grid lines?
A
a moving grid
21
Q
Exceeding the optimal kV range while maintaining good density will yield a film that has which of the following?
A
a long scale contrast (more shades of grey)
22
Q
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?
A
decrease it
23
Q
Which of the following would increase patient exposure?
A
using a 10:1 stationary grid
24
Q
Using an air gap technique is only for what films?
A
lateral, flexion, extension and oblique cervical flims
25
What technique was used in the 70s to prevent radiation from getting to the patient?
high kV technique
26
If you took a lateral cervical at 66kV at 100 mAs for 1/10 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 15%, do this before doubling mAs because kV isn't in optimal range
27
About how much increase in mAs is required when going from a non grid technique to using a 12:1 ratio technique?
5 times
28
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 kV
29
If you saw a blood vessel on end (axially) on a chest film it would probably look like which of the 4 natural body densities?
metal (it shows up white, like the blood vessel)
30
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
31
If you took an A-P lumbar on a thin patient using 85 kV at 100 mAs 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
32
You have an elderly overweight patient that you take an A-P lumbar film using 90kV with 100 mAs for 1 sec at 40" SID. When you look at the film you see that it is very grey and you need to retake it. Of the choices below, which would be the best way to proceed?
use 200 mAs and decrease kV 15%
33
You perform cervical films on a patient. The lateral was taken at 65 kV and 10mAs with out a grid and was light, but you could still see structures. What would be best to do to retake the film?
increase kV 15%
34
How many lines per inch are recommended for a stationary grid?
10-12
35
Which choice below is the main reason why a "fixed kV" technique is preferred?
contrast is consistent
36
```
If you took four A-P lumbar films:
1: 95kV, 6.25mAs
2: 106kV, 3.75mAs
3: 58kV, 60mAs
4: 85kV, 8mAs
Which has the lowest contrast?
```
second one (the higher the kV, the less contrast there is)
37
If you decided not to use a grid for an AP lumbar film and adjusted the radiographic technique to maintain a good density, what would be the outcome?
it would be grey
38
To double the density of a film with kV, you should apply which rule?
15% rule
39
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?
the 72" would be smaller and clearer
| 40" would be larger and less clear
40
Which of the following could be a problem if your x-ray tube was laterally shifted from the center of the film?
shape distortion
41
What is the primary purpose of a grid?
reduce scatter radiation of the film
42
Which of the following increases Compton's radiation?
higher kV
43
What is the optimal kV range for each of the spinal films?
cervical, AP thoracic, pelvis: 75-85
lat. thoracic, lat lumbar: 85-95
AP lumbar: 80-90
AP full spine: 80-100
44
When shopping for a grid, which interspacing material would you want for best x raying the spine?
aluminum
45
Which of the following best describes back scatter?
scatter that is directed toward the tube
46
If you wanted to alter your contrast so that a radiograph had more grey tones, what would you increase?
kV
47
Which effect does using a reciprocating grid have that a stationary grid doesn't?
blurs out grid lines
48
Of the following, which would produce a film with the most visible grainyness?
high kV, low mAs
49
```
If you took 4 lateral cervical films:
1: 75kV, 14mAs
2: 65kV, 14mAs
3: 85kV, 14 mAs
4: 95kV, 14 mAs
Which film would be the darkest?
```
the fourth one (most kV= more grey)
50
How much increase in mAs is needed to maintain the same denstiry when reducing the x-ray field from 14x17 to 8x10?
60%
51
What is true about the 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 source
52
A film exposed to secondary radiation will have which of the following appearances?
greys the film, making it darker
53
Which would be the most likely to decrease the amount of scattered radiation to a film?
increase in mAs
or decrese in kV?
54
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
55
Of the following, which would cause a decrease in subject density?
disuse atrophy
56
You get a grid that says "focused grid with a focal range of 40" to 72", 8:1 ratio, aluminum interspacing material." You tell the delivery man to take it back, why?
"the maximum recommended kV for an 8:1 grid is 90 and I might want to use more."
57
You have a variable kV technique. The a-P measurement in the lumbar region is 40 cm so you follow the steps in setting the mAs and kV. Considering the patient's age and rather 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
58
If you increased the MAS and reduced theKV from a given radiographic technique, what would be the outcome?
it would have more contrast
59
To decrease the density of a previously taken film by .5, which would you do?
decrease the Mas by 50%
60
If a film is too dark, it is said to be...?
Overexposed
61
Determine which radiographic technique would have the shortest scale of contrast
the one with the lowest KV
62
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
63
Which effect would adding 100% More MAS to a radiographic technique have?
double density of film
64
Which of the following best describes what you should expect if you retake an AP lumbar with 15% decrease in the KV and leave the MAS constant?
Density of film wouldbe reduced by half
65
If you have a radiograph of the lumbar spire that is too light, but you can see the bones on it and if you decide to solve your problem by the 15% rule, which would you do?
increase KV by 15%
66
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
67
A filament does what?
Forms electrons
68
Which radiographic technique would cause yhe most absorption of x rays in a patients body?
Most mAs
69
In which direction do grid lines run?
In the long axis of the patient
70
What is the most common cause of a blurry image in practice?
Patient motion
71
Whennusing a stationary grid, which of the followingbis recommended for spinal filming?
10:1 grid ratio
72
Contrast between structures of different subject densities is due to what?
Differential absorption
73
Which best describes the effect of scatter on a film?
Causes greying of the film
74
Which radiographic technique would demonstrate the most film grain?
HighbkV, high mAs, short time
75
What is the main function of mAs?
Film density
76
You have a film that is so light you cant see structures, what do you do to fix it?
Double mAs and increase kV 15%
77
When x raying an obese patient, which of the following would be helpful in obtaining a quality film?
lower kV in the optimal range
78
Osteoporosis will usually require you to do which of the following?
reduce tube output
79
Which would be the most likely to decrease the amount of secondary radiation to a film?
increase in mAs
80
Which radigraphic projections routinely uses an air gap technique?
lateral, flexion, extension oblique cervical
81
A film with a darkened overall grey appearance could be cause by which of the follwoign?
exposure of the film to scatter
82
Which of the following best describes the outcome of reducing the mAs by 1/2 and keeping the kV constant?
the film density would be decreased
83
To double the density by using kV, what would you do?
increase kV 15%
84
Which of the following would result in an increase in the amount of x rays passing through the patient without an interaction that would produce secondary radiation
higher kV
85
Which of the following radiographic projections should routinely use compensating filtration?
AP thoracic, lateral thoracic and full spine
86
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 image size on a 72 film
87
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
88
an accurate collimator should not allow more than what percent of the SID of light outside of the exposure field?
2%
89
Which of the following is the most effective in reducing secondary radiation?
filtration
90
Too high of kV will have which effect on the film?
quantum mottle
91
Which of the following statements is true about film densitry?
50% of the mAs is equal to 15% of the kV
92
Rays that exit the patient and hit the film are termed what?
primary rays
93
A lateral cervical film could use which of the follwing that a lateral thoracic or lumbar shouldn't?
an air gap
94
If you suspect a female has scoliosis and you are concerned about her breast tissue and gonads, what film technique should you use?
a full spine film with the patient facing the film
95
The higher the kv, the more what radiation is produced?
Compton
96
Which is referred for spinal filming?
Fixed kv technique
97
What is the advantage of a high kv trchnique?
Fixed kv technique
98
Which would absorb the most x rays in a patient?
Vertebra
99
Exceedkng the optimal kv range while mainatining good density yield a film that has whicj of the following?
Long scale contrast
100
Differential contrast = what?
Subject density
