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Flashcards in Test 4 Deck (39)
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1
Q

The source of Kinect of energy

A

Projectile electrons

2
Q

As Kvp increases, the ________ energy of projectile electrons

A

Higher

3
Q

Electrons travel at —— speed of light

_______ travel at the speed of light

A

1/2

Xrays

4
Q

Electrons emitted by the filament and directed to the target (cathode to anode)

A

Projectile electrons

5
Q

The strength of attachment of electrons to the nucleus

A

Binding energy

6
Q

X-rays produced by transitions of orbital electrons from the outer to inner shells

A

Characteristic X-rays

7
Q

X-rays produced by interaction of a projectile electron with a nuclear force
0-whatever KvP set.
Constant

A

Bremsstrahlung X-rays

Most xrays are brems

8
Q

X-ray quantity is…

A

X-ray intensity

Measured in air Kerma (mR)

9
Q

X-ray quality is measured in…

A

KvP

Penetrability of the X-ray beam

10
Q

The monoenergetic equivalent of an X-ray beam

A

Effective beam

11
Q

Section of metal added to the X-ray tube housing. Reduction in X-ray quantity; reduces patient exposure

A

Added filtration

12
Q

Anode heat is …….

A

Excitation

13
Q

Cascading

A

Inner electrons from each shell moves up.. X-rays are made with each placement

14
Q

Target material is made of

Filtration is usually made of

A

Tungsten

Aluminum

15
Q

Characteristic X-rays are made when

A

An outer shell fills an inner shell
K shell ionization

And tungsten have a discrete energy of 69kev

16
Q

Kinetic energy of electrons gets converted to

A

Heat!

17
Q

Discrete =

A

Characteristic

18
Q

Low energy X-rays
Lower than 10kev
Change direction with no loss of energy

A

Coherent classical Thompson or Rayleigh

19
Q

Affects the radiologist especially in flouro
Ionized atoms X-ray changes direction with a loss of energy

Outer shell electron interacts with moderate energy

No useful info on image
But greatly impacts image

A

Compton scattering

Higher levels of energy

20
Q
Ionization with inner shell 
Ejection of K shell 
Causes damage to patient 
X-rays totally absorbed 
Lower levels of energy
A

Photoelectric effect

21
Q

Secondary radiation is also called

A

Characteristic X-rays

22
Q

Photoelectric cannot occurs unless incident X-rays has energy _______________ than the electron binding energy

A

= or greater

23
Q

Absorbed by nucleus
10 mev
Nuclear fragments are emitted

A

Photodisintegration

24
Q

Must be 1.02,mev
Specifically in regards to Nuclear Medicine
Energy divided equally
Electrons split and make a + and - electron

A

Pair production

25
Q

Which interaction of matter is ALL or NOTHING absorption

A

Photoelectric

26
Q

Compton scattering is_________ absorbed

A

Partially

27
Q

2 tube interactions

A

Brems and characteristic

28
Q

To decrease density on an image we would __________ mAs

A

Increase

29
Q

If we increase KVP we must ________ mAs

15% rule

A

Decrease

30
Q

Low energy interact with
Moderate energy interact with
High energy interact with

A

Atoms

Electrons

Nucleus

31
Q

Energy potential in characteristic X-rays depends on the

A

Target material or Tungsten

32
Q

Lower energy levels of radiation interact with

High energy levels

A

Bones, tissues

Pass through the body

33
Q

Inherent filters are

A

Built into the tube housing and made of aluminum

34
Q

Trough

Bow tie

Step wedge

A

Chest

CT

Don’t use

35
Q

Monoenrgetic energy is

A

1 type of energy that removes low energy

36
Q

Projectile electrons convert __________ to __________

A

Kinetic to heat

37
Q

Filaments produce

A

Electrons

38
Q

3 absorptions

A

Radiolucent- through the body
Radiopaque-absorbed in the bone
Attenuation -partially absorbed

39
Q

Added filtration increases ——_

A

half value layer HVL