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Flashcards in Chapter 12 Deck (31)
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1
Q

X-rays that exit the patient and interact with the image receptor

A

Image-forming x-rays

2
Q

x-rays that remain as the useful beam exits the patient

A

exit x-ray beam

3
Q

medium that convert x-ray beam into visible image

A

image receptor

4
Q

emulsion coated on both sides of a film is called the:

A

double-emulsion film

5
Q

Ensures uniform adhesion of the emulsion to the base

A

adhesive layer

6
Q

the protective covering of gelatin which encloses the emulsion

A

overcoat

7
Q

thickness of a radiographic film

A

150-300 micrometer

8
Q

the foundation of a radiographic film

A

base

9
Q

property of the base

A

dimensional stability

10
Q

added to the base of the film to prevent eye strain

A

dye

11
Q

original radiographic film

A

glass plate

12
Q

types of radiographic film base:

A
  1. glass plate
  2. cellulose nitrate
  3. cellulose triacetate
  4. polyester
13
Q

the standard base, this base is flammable

A

cellulose nitrate

14
Q

known as the “safety base”, has the same property with the standard base but its not flammable

A

cellulose triacetate

15
Q

the film base choice, it is more resistant to warping from age and is stronger than cellulose triacetate, also permits easier transport through automatic processors

A

polyester

16
Q

the heart of the radiographic film

A

emulsion

17
Q

emulsion consists of two homogenous mixture

A

gelatin

silver halide crystals

18
Q

thickness of a film emulsion

A

3-5 micrometer

19
Q

the active ingredient of the radiogragic emulsion

A

silver halide crystals

20
Q

silver halide crystal

A

silver bromide 98%

silver iodide 2%

21
Q

atomic numbers

A
iodide = 53
bromide = 35
silver = 47
gelatin = 7
22
Q

types of silver halide composition

A
  1. tabaular
  2. cubic
  3. octahedral
  4. polyhedral
  5. irregular shapes
23
Q

most common grain of the silver halide crystal used in the film emulsion

A

tabular grain

24
Q

silver halide crystals are made through:

A

dissolving mettalic silver (Ag) in nitric acid (HNO3)to form SILVER NITRATE (AgNO3)

silver bromide (AgBr) is made through mixing SILVER NITRATE and POTASSIUM BROMIDE (KBr)

25
Q

the imperfection of the film is thought to be responsible is a chemical contaminant called the

A

silver sulfide

26
Q

The contaminant “silver sulfide” is also known as the

A

sensitivity center

27
Q

this is where the photoelectrons and silver ions interact to combine

A

latent imaging center

28
Q

direct exposure film contains thicker emulsion which explains why DE film is superior/ has greater detail than in a double emulsion film

A

the size and the concentration of the SHC affects the film speed

29
Q

high contrast emulsion consist of SMALLER silver halide crystals

A

low contrast consist of larger grains

30
Q

larger grains emulsion are more sensitive than SMALL-GRAIN EMULSION

A

take note

31
Q

3 critical characteristics of a crossover layer

A
  1. absorbs most of the crossover light
  2. does not diffuse into the emulsion but remains as a separate layer
  3. completely removed during processing