Exam II Flashcards
If you make an exposure at 100 mAs with 80 kV and the radiographic density is good, what would be the outcome if you x-rayed the same part of the same person a second time with 50 mAs and 92 kV?
The first film would have the higher contrast
What is undesirable with magnification distortion?
A. Object altered in shape
B. Borders of object will be blurred
C. Borders of object will be darker
D. Object will appear smaller
B. The borders of the object will be blurred
What is the outcome of reducing the mAs by 1/2 and keeping the kV and the distance constant?
The film density would be decreased
With which percentage in mAs would yo uexpect to see the slightest change in radiographic density?
30%
If you took 4 A-P lumbar films, the first with 95 kV and 6.25 mAs, the second with 106 kV and 3.75 mAs, the third with 58 kV and 60 mAs and the fourth at 85 kV and 8 mAs, which would have the lowest contrast?
The second film
Osteoporosis will usually require you to do which of the following?
A. Reduce tube output
B. Increase tube output
C. Develop films faster
D. Pump up the patient
A. Reduce the tube output
Which of the following would produce the same film density as 200 mA for 0.5 seconds?
A. 300 mA for 1.5 sec
B. 250 mA for .75 sec
C. 150 mA for 2 sec
D. 100 mA for 1 sec
D. 100 mA for 1 second``
To double the density of a filming using kV, what would you do?
Increase kV by 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 radiographic technique, what would you find?
The 72” film will have a smaller and clearer image, while the 40” film will be larger and less clear
Which of the following could be a problem if your x-ray tube was laterally shifted from the center of the film?
A. Magnification distortion
B. Shape distortion
C. Image blurring
D. Unequal filtration
B. Shape distortion
The number of electrons will be doubled if what happens?
Increasing the mAs by 2 times
Which is true about the air-gap technique when normally used in a cervical spine series?
A. It makes the vertebra appear larger
B. It requires a longer tube distance
C. It usually doesn’t require the use of a grid
D. It is best used with the A-P cervical film
C. It usually doesn’t require the use of a grid
The higher the kVp, the more _____ radiation is produced.
Compton’s
What is the range of body part thickness when a grid should first be considered advantages to use?
10-15cm
If you wanted a film with more blacks and whites and less gray, what would you do?
Use a low kV and high mAs technique
Which of the following is true about grids?
A. They increase patient radiation
B. They should be used with smaller body parts
C. They should not be used with films of the pelvis
D. They work best if the lead strips are parallel
A. They increase patient radiation
Generally speaking, adding 4 kVp to a radiographic technique with a single phase machine would be equivalent to what?
Increasing the mAs by 30%
What would produce a film with the most visable grainy?
A high kVp/low mAs film
What is the recommended optimal kV range for an A-P thoracic film?
75-85 kV
What is the primary factor for radiographic density?
mAs
Which radiographic technique would cause the most absorption of x-rays in a patient’s body?
A. 10 mAs with 140 kV
B. 20 mAs with 90 kV
C. 30 mAs with 60 kV
D. 40 mAs with 40 kV
D. 40 mAs with 40 kV
The more mAs, the more absorption!
Which of the following is the closest to what is recommended for spinal filming with a stationary grid?
A. 8:1 with 100 lines per inch
B. 10:1 with 100 lines per inch
C. 12:1 with 200 lines per inch
D. 16:1 with 200 lines per inch
B. 10:1 with 100 lines per inch
10:1 or 12:1 with 100 lines is the range
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%
You send your associate to take lumbar x-rays on a 330 pound retired male wrestler who has a stomach ache. He takes the films in the recumbent position for the best possible quality. After seeing the first film, he tells you it’s too light. Due to the man’s size and the fact that you can see the spinal structures, the best thing to do would be to?
Increase the mAs by 100% (double it)