問題一覧
1
this absorbs scatter radiation
Grid
2
distortion of definition on an image
Object Unsharpness a.k.a Blurring
3
what is the suggested SID for chest - extremities -
- 72 cm SID - 40 cm SID
4
does automatic collimation
Positive Beam Limitation
5
use of devices to confine x-ray ex. Collimators, cones/cylinder, diaphragms
Beam Limitation
6
magnification of anatomical structure
Size Distortion
7
Shape distortion is caused by _____?
Angles
8
the shadow on the side, causes unsharpness
Penumbra
9
called the concept that color of light emitted must match the light sensitivity of the film
Spectral Matching
10
shadow focused on the object
Umbra
11
What are the 2 processing errors?
- Overexposed - Underexposed
12
- use of attenuating material - this absorb low energy x-rays Materials are: tungsten, copper, aluminum
Filtration
13
Types of Grid
- Parallel - Cris Cross
14
- determines image quality - determine amount of detail - determined first by geometry of image formation
Sharpness
15
What affects recorded detail? MDFS
- Motion - Distance - Focal Spot Size - SID/OID
16
2 Types of Motion
- Voluntary - Involuntary
17
What happens when the chemical temperature is too hot? causes chemical fog What happens when the chemical temperature is too cold?
- Density increases - Density decreases
18
attenuating material that reduces the intensity of the beam to half its value
Half Value Layer
19
When the chemical is new, the factor is ? When the chemical is old, the factor is ?
- Increased - Decreased
20
focal spot that causes image sharpness
Small Focal Spot