問題一覧
1
The positive beam limiting device (PBL) assures that the x-ray beam is collimated to _________.
1 cm outside image receptor size
2
The use of ________ improves contrast and reduces patient dose.
collimation
3
The most commonly used beam restricting device is the ________.
variable collimator
4
Which kVp selection would result in the most scattered x-rays in the image-forming beam?
90 kVp
5
Lowering kVp ____ patient dose and ______ image contrast.
increases; increases
6
Image-forming x-rays include those which have been ________.
transmitted without interaction and scattered through Compton interaction
7
The x-rays that are transmitted through the patient without interaction contribute to _________.
useful information
8
The x-ray interaction that contributes to the clear parts of the image is _____.
photoelectric interaction
9
The three primary factors influencing the intensity of scatter in the image-forming beam are ________.
kVp, field size, and patient thickness
10
Approximately __% of the x-ray beam incident on the patient is transmitted through the patient without interaction to become part of the image-forming beam.
1
11
Decreasing the kVp will increase ______.
patient pose
12
Photoelectric interactions increase when _____ is decreased.
kVp
13
Scatter radiation increases as ________ increases.
field size
14
The use of a compression device will increase _____.
image contrast
15
Contrast resolution is improved by _________.
tight collimation, lowering kVp and patient compression
16
A fixed aperture diaphragm should leave a ___cm unexposed border on the film.
1
17
Beam restriction with a(n) ______ is only accurate at a fixed SID.
aperture diaphragm
18
Federal regulations passed in ____ required that positive beam limiting devices be on all manufactured x-ray collimators.
1974
19
Compton scatter contributes to _______.
image noise
20
How can you improve image contrast with a heavy patient without increasing patient dose?
Use tight collimation.