Materials used in recording Invisible x-ray image

Question 1

Layers of X-ray film

Answer 1

1. Supercoat
2. Emulsion layer
3. Adhesive layer
4. Base
5. Adhesive layer
6. Emulsion layer
7. Supercoat

Question 2

Base

Answer 2

• Provide support to the for the emulsion layer.
• Transmit light for the image to be viewed.
• Strong and flexible to withstand chemical stress
• Impermeable to water
• chemically inactive
• uniform in color
• non-flammable

Question 3

Adhesive layer is made of what

Answer 3

Mixture of ;
*gelatin solution
* Solvent of film base

Question 4

Adhesive layer

Answer 4

• ensures that the emulsion layer sticks to the base material during coating stage in manufacturing.
• Prevents any separation of the emulsion layer during processing.

Question 4

Emulsion layer is made of what

Answer 4

*Silver halide crystals
they’re suspended in gelatin

Question 4

Emulsion layer

Answer 4

Its where the invisible image is captured( latent image)

Question 5

Gelatin

Answer 5

• A medium for growth of Ag
• Allows the film base to be evenly coated with warm liquid emulsion.
• Increase the ability pf AgH to store the latent image
• Holds metallic silver in place
• Permeable therefore it allows active ingredients to react with AgH during processing

Question 5

Supercoat

Answer 5

• Made of pure gelatin
• Protect the sentive emulsion layer from light pressure or abrasions.
• Provide suitable surface characteristics( the film should be glossy to prevent dust accumulation)

Question 5

Storage of x-ray films

Answer 5

• Temp ranges between 10 and 24 degrees celcius
• Humidity between 30% and 50%
• Should be stored in light-tight containers or cabinets
• Clean and dry environment( free from dust, dirt and moisture)

Question 6

Intensifying screen

Answer 6

is a plastic sheet coated with fluorescent materials called phosphors.

Question 6

Phosphors

Answer 6

Materials that convert photon energy to light

Question 6

Luminescence

Answer 6

The emission of light from a substance bombarded by radiation.

Question 7

Types of luminescence

Answer 7

• Fluorescence
• Phosphorescence

Question 8

Fluorescence

Answer 8

Here luminescence only happens during the period of irradiation and will terminate at completion of the x-ray exposure.

Question 9

Phosphorescence

Answer 9

The irradiated material continues to emit light after the exposure.

Question 9

Uses of luminescent effect in radiography

Answer 9

• to obtain image on a fluorescent screen as in fluoroscopy.
• to increase the photographic response of the silver halide emulsion

Question 9

Plastic base

Answer 9

Made of plastic material on which the phosphor material is coated.

Question 10

Parts of an intensifying screen

Answer 10

1. Protective layer
2. Luminescent layer
3. Reflecting layer (TiO2)
4. Base

Question 10

Reflecting layer of intensifying

Answer 10

intercepts light heading in other direction and directs it to the film.

Question 10

Luminescent layer

Answer 10

Absorbs x-ray photons and converts them to visible light that is recorded on the film.

Question 10

what materials are used to make the luminescent layer

Answer 10

phosphors

Question 10

examples of phosphors

Answer 10

*Calcium tungstate( CaWO4)= Blue light
* Lanthanum oxybromide (LaOBr)= Blue light
* Gadolinium Oxysulfide(Gd2O2S): Green light

Question 10

Characteristics of Intensifying screens

Answer 10

• Chemically inert
• Not discolor with age
• Radioparent base
• should not curl

Question 11

X-ray cassettes

Answer 11

a light resistant container that holds the film between 2 intensifying screens.

Question 11

Construction of x-ray cassettes

Answer 11

* The front is made of a low Z material to enable ease passage of x-rays. (plastic, carbon) * The back is made of high Z material (lead to reduce back scatter)

Question 11

Differences between x-ray cassettes used in conventional radiography and mammography.

Answer 11

* X-ray cassettes in conventional radiography have 2 intensifying screens mounted on two sides of the cassettes while in mammography only one intensifying screen.

Question 11

Imaging plates

Answer 11

*Coated with photostimulable phosphors, used in CR. * The phosphors store x-ray energy in gaps of the crystalline structure forming a latent image.

Question 11

Layers of imaging plates

Answer 11

1. Protective layer 2. Phosphor 3. Base 4. Absorbing light layer 5. Protective layer 6. Label of code

Question 12

Protective layer of the imaging plate

Answer 12

A thin, tough, clear plastic for protection of the phosphor layer

Question 12

Phosphor/ active layer

Answer 12

Layer pf photostimulable phosphors, that traps and stores x-ray energy during exposure. made of barium fluorohalide

Question 13

Colour layer of the imaging plate

Answer 13

Influences the color of the light emitted during the reading process

Question 14

Base

Answer 14

semi-rigid material that gives the imaging sheet some strength

Question 15

Backing layer

Answer 15

soft polymer that protects the back of the cassette

Question 16

Can you explain how intensifying screens enhance image quality in cassettes?

Answer 16

improve the quality of radiographic images by enhancing the effects of X-ray photons and reducing the necessary exposure, which benefits both the patient and the quality of the diagnostic image