Keiser University Radiation Therapy Rat1001 Intro To Radiation Therapy Week 4

Front 1

What are four requirements for x-ray production?

Back 1

Vacuum(tube housing);

Source of electrons(filament);

Method toaccelerate the electrons (voltage)

rapidly;

Method to stop electrons (target)

Front 2

What is remnant radiation?

Back 2

beam able to exit the patient to make the image.

Front 3

Scatter radiation

Back 3

Photons that interact with matter, causingchange in direction

Front 4

What are the two types of distortion?

Back 4

Elongation and Foreshortening

Front 5

What can cause distortion?

Back 5

inaccurate alignment of the central ray

Front 6

What does the inverse square law refer to?

Back 6

intensity of the beam inversely relative to distance

Front 7

What does direct square law refer to?

Back 7

mAs/Density exposure

Front 8

what does penumbra mean?

Back 8

Fuzziness or unsharpness around the field edges

Front 9

What is the most common cause of imageunsharpness?

Back 9

Movement, motion

Front 10

What is remnant radiation?

Back 10

The resulting beam that is able to exit thepatient and product an image in the image receptor.

Front 11

Intensifying screen arewhat?

Back 11

Thinlay of polyester plastic coated with layers on luminescent phosphor crystals.

Front 12

When insufficient light isemitted from the phosphor, it produces an image that is grainy, the conditionis known as what?

Back 12

Quantum Mottle or quantumnoise

Front 13

There is an invisible imagecalled a ________ ________that is stored in the emulsion until it is processed.

Back 13

Latent image

Front 14

Radiolucent means materials allow x-ray photonsto pass through easily translucent panes of glass allow the passage of light?

True or False

Back 14

True

Front 15

Radiopaque materials arenot easily transversed by x-ray photons?

True or Fals

Back 15

True

Front 16

PrimaryRadiation

Back 16

The beam of photons before they interact with the patient’sbody

Front 17

Charged-CoupledDevice

Back 17

Uses a chip to convert light photons to electrical charge

Front 18

IndirectCapture

Back 18

Also use TFTs, is a two-step process: x-rays are firstconverted to light using a scintillator, and the light is then converted to anelectric signal, there are two types of devices – charged-coupled device (CCD)and the thin-film transistor array (TFT)

Front 19

kVp controls

Back 19

Contrast,quality

Front 20

mAscontrols

Back 20

Density, quality

Front 21

Opticaldensity

Back 21

More dense matter shows less optically dense onradiograph.

Front 22

The "Central Point" of the body where isocenter is set.

Back 22

SAD - Source to Axis Distance

Front 23

If the bone in your x-ray is too dark, you probably have __________ set too high.

Back 23

kVp

Front 24

Decreasing ________________ decreases image receptor exposure, film density, and patient exposure.

Back 24

mAs

Front 25

Two terms to describe controlling image quality and quantity by selecting the appropriate exposure are _______________ and ____________

Back 25

Prime Factors and Technique

Front 26

_______________, ____________, and _________________ radiation all come from the nucleus. Of these, ____________ is the most penetrating.

Back 26

Alpha, Beta, and GammaGamma