Opaque to x-rays

Invisible to x-rays

Metal

Air

The beam is more concentrated on the cathode side

The beam is more concentrated on the anode side

The imaginary line following the centremost part of the beam

The imaginary line following the outermost part of the beam

The beam is more concentrated on the cathode side

The beam is more concentrated on the anode side

An imaginary line following the centremost part of the beam

An imaginary line following the outermost part of the beam

Smaller

Larger

Yes - it causes sharpness of the image and decreases the patient's radiation dose

No - it causes unsharpness of the image and increases the patient's radiation dose

Collimator

Target (anode)

Filament

Grid

Reflects/absorbs the x-rays

Concentrates the beam

Close to the Bucky, far away from the tube

Far away from the Bucky, close to the tube

Close to the Bucky, close to the tube

Far away from the Bucky, far away from the tube

Relationship between the height of the lead strips and the width of the spaces between them

Relationship between the weight of the lead strips and the width of the spaces between them

Parallel

Angled - matches angles of the x-rays exiting the patient, must be used with the tube at a specific distance away

Moving - increases efficiency and hides any lines that may be caused by the grid material

Parallel

Angled - matches angles of the x-rays exiting the patient, must be used with the tube at a specific distance away

Moving - increases efficiency and hides any lines that may be caused by the grid material

Parallel

Angled - matches angles of the x-rays exiting the patient, must be used with the tube at a specific distance away

Moving - increases efficiency and hides any lines that may be caused by the grid material

Controls the penetrating power of the x-ray beam

Controls the number of electrons crossing from the cathode to the anode

The time that the electrons are allowed to cross the tube for

Controls the number of electrons crossing from the cathode to the anode

Controls the penetrating power of the x-ray beam

The time that the electrons are allowed to cross the tube for

Anode

Cathode

Filament

3400 revolutions

3000 revolutions

3200 revolutions

3600 revolutions

Filament and focusing cup

Filament and bearings

Bearings and rotor

Rotor and focusing cup

Cloud of electrons (thermionic emission)

Cloud of protons (thermionic emission)

Cloud of atoms (thermionic emission)

Positively

Negatively

Encounters a smaller area of the target

Encounters a larger area of the target

All directions

Forwards

Backwards

Laterally

Beam travelling towards the patient

Beam travelling away from the patient

Beam travelling upwards through the patient

Beam travelling downwards through the patient

Absorbs the heat that is produced

Reduces the scatter

Decreases the amount of electron penetration

Decreases the number of electrons of energy in the beam

Increased

Decreased

Compton scatter

Compton electron

Recoil electron

Photon - becomes recoil/Compton electron

Neutron - becomes recoil/Compton electron

Electron - becomes Compton scatter

Photon - becomes Compton scatter

Retains the remainder energy, but changes course (scatters) in a random direction

Increases its energy, but changes course (scatters) in a random direction

Decreases its energy, but changes course (scatters) in a random direction

Decrease

Increase

Less image

More image

More mA's

Less mA's

Higher patient dose

Produces more scatter

Decreases clarity of the image

Contrast

Sharpness

Overall darkness of the image

Overall lightness of the image

10%

15%

20%

5%

100%

80%

120%

90%

1

2

3

4

Smaller target

Larger target

Object-image distance (OID) - small

Object-image distance (OID) - large

Source-image distance (SID) - small

Source-image distance (SID) - large

Long

Short

Yes

No

When there is too much energy penetrating the patient

When the anatomy lies at an inappropriate angle to the receptor, or vice versa

To eliminate as much scatter as possible as it exits the patient and before it reaches the receptor

To eliminate as much scatter as possible as it enters the patient

To focus the scatter before it reaches the receptor

To decrease the amount of radiation to the patient

Height divided by the interspace thickness

Number of grid strips per centimetre

Number of grid strips per centimetre

Height divided by the interspace thickness

Parallel

Diagonal

Criss-cross

At the central section of the grid

At the outermost section of the grid

Over the whole grid

Linear/parallel grid

Focused

Crossed

Static

Moving/reciprocating

Focused

Linear/parallel

Static

Crossed

Moving/reciprocating

Whole grid

Centre portion of the grid

Outermost portion of the grid

Blur the shadows of the grid strips so they're not visible on the image

To decrease the amount of radiation

To improve the contrast of the image

Reduces the dose

Decreases the time exposed to the radiation

The image becomes clearer

Intensifying screens and film

Film and filament

Receptor and grid

Glass envelope and bearings

Amplifiers - they convert the x-rays into visible light which then interacts with the film

Depressors - they convert the x-rays into visible light which then interacts with the film

Crystals - image obtained depends on the size of these crystals

Protons - image obtained depends on the amount of these protons

The emulsion is set to match the colour of light being emitted by the intensifying screens

The base is lightly tinted (pale blue or grey) to match the colour of light being emitted by the intensifying screens

Silver halide crystals are active in the emulsion

The emulsions are covered by a fine, translucent protective layer

1) Protective coating
2) Phosphor (emulsion) layer
3) Reflective layer
4) Base

1) Protective coating
2) Reflective layer
3) Phosphor (emulsion) layer
4) Base

Strong, flexible, chemically inert material (e.g. plastic)

Weak, flexible, chemically inert material (e.g. plastic)

Strong, solid, chemically inert material (e.g. plastic)

Weak, solid, chemically inert material (e.g. plastic)

Yes

No

So the x-ray absorption is high

So the x-ray absorption is low

So the light emitted from the x-ray beam is high

So the light emitted from the x-ray beam is low

Large amount of light per absorption of x-ray photons

Small amount of light per absorption of x-ray photons

Maximal

Minimal

Yes

No

Crystals

Electrons

Protons

Light waves

Small

Medium

Large

More exposure to produce the same amount of image than screens with larger crystals - more dose

Less exposure to produce the same amount of image than screens with larger crystals - less dose

Areas away from the torso

Lumbar spine

Pelvis

Thoracic spine

All directions

Diagonally

Vertically

Horizontally

Redirects the light emitted from the phosphors, so as much light as possible is travelling towards the film

Redirects the scatter away from the receptor, so a minute amount of scatter is travelling towards the film

1%

10%

70%

50%

Fine translucent layer to protect the phosphors from dust and abrasion

Thick translucent layer to protect the phosphors from dust and abrasion

Fine coloured layer to protect the phosphors from dust and abrasion

Silver halide crystals

Gold halide crystals