V-Jan/feb

Front 1

The ________ is the most important part of the x-ray machine because this is where the x-rays are actually produced.

Back 1

X-ray tube

Front 2

The two main components of the cathode assembly are the ____ and the _____

Back 2

filament, focusing cup

Front 3

The main components of a rotating anode assembly are the anode, ____ and _____.

Back 3

stator, rotor

Front 4

The cathode is considered the positive side of the x-ray tube.

Back 4

False

Front 5

When facing an x-ray tube, the anode must always be orientated on the left side/end of the x-ray tube or x-ray production will not be possible.

Back 5

False

Front 6

The filament is the source of electrons (where electrons are generated) during x-ray production.

Back 6

True

Front 7

Most x-ray tubes are referred to as dual-focus tubes because they use two filaments: a large filament and a small filament.

Back 7

True

Front 8

The target is the part of the cathode that is struck by the focused stream of electrons coming from the anode.

Back 8

False

Front 9

The most common anode used in diagnostic radiology is the stationary anode because it can withstand high heat loads in one specific area versus dissipation of the heat load around a target assembly.

Back 9

False

Front 10

Because tungsten has a low atomic number and a high melting point, it efficiently produces x-rays.

Back 10

False

Front 11

The focusing cup is made of nickel, has a negative charge, and keeps the cloud of electrons emitted from the filament from spreading apart.

Back 11

True

Front 12

The target is bombarded by electrons and thus creates the opportunity for the production of x-rays.

Back 12

True

Front 13

The stator is an electric motor that turns the rotor at very high speed during x-ray production.

Back 13

True

Front 14

Leakage radiation refers to any x-rays, other than the primary beam, the escape the tube housing.

Back 14

True

Front 15

The face of the rotating anode is angled to help the x-ray photons exit the tube.

Back 15

True

Front 16

Concerning a rotating anode, the actual focal spot is the physical area of the target that is bombarded by elections during x-ray production.

Back 16

True

Front 17

Thermionic emission refers to the boiling off of electrons from the filament.

Back 17

True

Front 18

The KVP level, which depends on the actual KVP value set on the control panel by the technologist, is applied across the tube from the cathode to the anode and determines the speed at which the electrons in the tube current move.

Back 18

True

Front 19

Concerning the Anode Heel Effect, x-rays are more intense on the ___ of the tube. The intensity of the x-rays decrease toward the ___.

Back 19

cathode side, anode side

Front 20

The electrons that move from the cathode to the anode travel extremely fast. The moving electrons, which have kinetic (______) energy, strike the target of the anode and interact with the tungsten atoms in the anode to produce x-rays or ____.

Back 20

energy due to motion, photons

Front 21

primary radiation is emitted from an interaction occurring at the ___

Back 21

target

Front 22

The most common diagnostic radiographic target angle is

Back 22

Twelve degrees

Front 23

Concerning the Anode Heel Effect, the radiation intensity is greater on the

Back 23

Cathode side

Front 24

There are two types of target interactions that can produce primary radiation, they are

Back 24

Bremsstrahlung and Characteristic

Front 25

What interaction occurs when an ejected electron causes a cascade effect within an atom?

Back 25

Characteristic interactions

Front 26

Concerning photon production, within the x-ray diagnostic range, what target interaction does not occur below 70 KVP?

Back 26

Characteristic

Front 27

_____ occurs when an incident electron interacts with the force field of the nucleus

Back 27

Bremsstrahlung

Front 28

In the diagnostic energy range, most x-ray interactions are_____.

Back 28

Bremsstrahlung

Front 29

At 100 kVp, protons can be created at the target by _____

Back 29

Bremsstrahlung and Characteristic

Front 30

The photon energy emitted is exactly the difference between the entering and exiting kinetic energy of the electron. No orbital electrons of the atom were affected. Describe this interaction

Back 30

Bremsstrahlung

Front 31

To produce photons, (primary radiation) within the diagnostic range, the incident electron must interacts with the ______.

Back 31

K-shell

Front 32

What is considered to be a point source of x-ray photons?

Back 32

Target

Front 33

What is the function of the filament?

Back 33

To provide sufficient resistance to the flow of electrons to cause thermionic emission

Front 34

The anode target surface is where the high-speed electrons from the filament are stopped in the production of x-ray photons.

Back 34

True

Front 35

A common cause of tube failure is bad bearings caused by long use at high temperatures.

Back 35

True

Front 36

Vaporization of the focal track occurs with normal rotating anode use.

Back 36

True

Front 37

Stationary anodes have a dynamic target area.

Back 37

False

Front 38

Which term is used to describe that area of the focal spot that is projected out of the tube toward the object being radiographed?

Back 38

Effective focal spot

Front 39

The entire cathode assembly and all the anode assembly except the stator are enclosed within the glass metal envelope.

Back 39

True

Front 40

The primary function of the envelope is to maintain the vacuum b/t the cathode and the anode.

Back 40

True

Front 41

Holding the rotor for a few seconds prior to making an exposure, rather than completely depressing the entire exposure switch at one time, will prolong the life of the x-ray tube.

Back 41

False

Front 42

The actual focal spot is used to describe the area of the focal track that is physically impacted or bombarded by the incident electron within the x-ray tube.

Back 42

True

Front 43

Almost all of the kinetic energy of the incident electron is converted to

Back 43

Heat

Front 44

Bremsstrahlung interactions may occur only when the incident electron interacts with a(n)

Back 44

Outer shell electron

Front 45

At the end of the characteristic cascade, the ____ shell is missing an electron

Back 45

Outermost

Front 46

The energy of characteristic photon is

Back 46

the difference b/t of the outer and inner shells b/t which the electron dropped

Front 47

Filament saturation occurs when the negative charge of the electron cloud opposes the emission of additional electrons from the filament.

Back 47

False

Front 48

In a brems interaction, the closer the incident electron travels to the nucleus, the lower the energy of the resultant x-ray photon.

Back 48

False

Front 49

The electron ejected during a characteristic interaction is also known as the x-ray photon.

Back 49

False

Front 50

The filament is set in the cathode assembly outside of the focusing cup.

Back 50

False

Front 51

To prolong the life of an x-ray tube, the exposure switch should be partially depressed for a few seconds before complete depression occurs.

Back 51

False

Front 52

The entire cathode and anode assemblies are enclosed within the glass or metal envelope.

Back 52

False

Front 53

Electrons in the thermionic cloud are driven from cathode to anode with 100% efficiency.

Back 53

False

Front 54

Like the cathode, the anode comprises a single metal called tungsten.

Back 54

False

Front 55

As the kinetic energy of the incident electron increases, so does the efficiency of the photon production.

Back 55

True

Front 56

Most x-ray tubes have a dual-focus arrangement.

Back 56

True

Front 57

According to the anode heel effect, the radiation intensity is grater on the anode side.

Back 57

False

Front 58

What are materials of choice for the filament?

Back 58

Tungsten, rhenium, molybdenum

Front 59

The types of target interaction that occur in the production of diagnostic range x-ray photons are dependent upon?

Back 59

Electron kinetic energy

Front 60

During a characteristic interaction, the dropping of a higher-energy state electron into a lower -energy state “hole” results in the emission of?

Back 60

A photon of energy

Front 61

What are the parts of the cathode assembly?

Back 61

Filament, focusing cup, associated wiring

Front 62

Insulation of the high-voltage components of the tube and absorption of the heat produced by x-ray production is achieved through the use of ?

Back 62

Dielectric oil

Front 63

Characteristic interaction occurs only when the incident electron interacts w/?

Back 63

Inner-shell electron

Front 64

The focusing cup has a___ charge?

Back 64

Negative

Front 65

What % of target interaction results in the production of x-ray photons>

Back 65

1%

Front 66

The rotor is located ___ the stator and ___ the envelope.

Back 66

Inside, inside

Front 67

Melting of the anode commonly occurs

Back 67

When the stator fails & the rotor ceases to turn

Front 68

The energy of a brems photon is?

Back 68

Difference b/t the entering & exiting kinetic energy of the electron

Front 69

What effects the production of the thermionic cloud?

Back 69

Filament diameter, filament length, filament temperature

Front 70

During a characteristic interaction, the energy of the incident electron must be ___ the electron it knocks from its orbit.

Back 70

Greater than that of

Front 71

Which condition is needed to produce an x-ray?

Back 71

A source of electrons, a vacuum, a large potential difference

Front 72

The function of the cathode is to produce?

Back 72

A thermionic cloud

Front 73

As more & more electrons build up in the area of the filament, their negative charges oppose the emission of additional electrons. This is known as?

Back 73

Space charge effect

Front 74

X-ray photon production occurs where?

Back 74

The anode

Front 75

The exact point in the x-ray unit where photons are crated is?

Back 75

Focal spot

Front 76

The K-shell can hold a max of ___ electrons?

Back 76

Two

Front 77

The function of the stator & rotor assembly is to?

Back 77

Rotate the anode

Front 78

The thermionic cloud is composed of

Back 78

electrons that have been boiled off

Front 79

Cathode Assembly’s functions are

Back 79

produce a thermionic cloud, conduct the high voltage, focus the electron stream

Front 80

Filament is part of the ____ Assembly

Back 80

Cathode

Front 81

Focusing Cup is part of the ____ Assembly

Back 81

Cathode

Front 82

What is the function of the Filament?

Back 82

The source of electrons

Front 83

The “MA” station selected affects

Back 83

the amount of current sent to the filament

Front 84

The “ MA” station selected

Back 84

determines the size of the thermionic cloud

Front 85

A shallow depression in the cathode assembly and is designed to house the filament. (It nearly surrounds the filament) is called a

Back 85

Focusing Cup

Front 86

It is made of nickel

Back 86

Focusing Cup

Front 87

It has a negative charge. (which keeps the cloud of electrons from spreading apart)

Back 87

Focusing Cup

Front 88

Anode is part of the ____ Assembly

Back 88

Anode

Front 89

Stator is part of the ____ Assembly

Back 89

Anode

Front 90

Rotor is part of the ____ Assembly

Back 90

Anode

Front 91

It is an electric motor and located outside of the x-ray tube envelope

Back 91

Stator

Front 92

What is the function of the stator?

Back 92

turns the rotor at a very high speed during x-ray production

Front 93

Maintains the vacuum between the cathode and the anode

Back 93

Envelope

Front 94

Insulates the high-voltage components from the tube housing, which is handled by the technologist. Absorbs much of the heat that is produced by the x-ray production process.

Back 94

Insulating Oil (dielectric)

Front 95

Equipped with a window to permit unrestricted exit of the useful photons from the envelope window. Many include a small fan for remove heat from the housing.

Back 95

Tube Housing

Front 96

Composed of photons that were not produced at the focal spot.

Back 96

Off-Focus Radiation

Front 97

Scattered electrons or photons which produce photons away from the focal spot

Back 97

Off-Focus

Front 98

Size refers to the focal spot size as measured directly under the anode target.

Back 98

Effective Focal Spot

Front 99

Based on the line-focus principle, the amount of anode angle determines the size of the

Back 99

effective focal spot

Front 100

How are the photons actually produced?

Back 100

Bremsstrahlung and Characteristic Interactions

Front 101

The closer the incident (incoming) electron gets to the nucleus as it travels past it, the greater the amount of kinetic energy that will be lost which will result in a higher energy brems photon.

Back 101

True

Front 102

An incident electron can lose any amount of its kinetic energy in an interaction with the nucleus of a target atom, and the bremsstrahlung photon associated with the loss can take on corresponding values.

Back 102

True

Front 103

Characteristic interactions may occur only when the incident electron interacts with any inner-shell electron and knocks an orbital electron out of orbit

Back 103

True

Front 104

The polyenergetic x-ray beam produced at the anode exits the tube housing to______________.

Back 104

Become primary beam

Front 105

The _______are unable to penetrate the anatomic part and do not contribute to image formation. They contribute only to patient dose.

Back 105

Low energy photons

Front 106

To reduce the low-energy photons, ______is added by inserting absorbing material(s) into the primary beam in order to attenuate or absorb these photons.

Back 106

Filtration

Front 107

Any material designed to selectively absorb photons from the primary x-ray beam is called a ____.

Back 107

filter

Front 108

Filtration that is permanently in the path of the x-ray beam and is the composition of the tube and housing is called ______

Back 108

Inherent Filtration

Front 109

What type if filtration is the oil that surrounds the tube?

Back 109

Inherent

Front 110

What type if filtration is the thisckness of the glass envelope?

Back 110

Inherent

Front 111

What type if filtration is the glass window of the housing?

Back 111

Inherent

Front 112

Any filtration the occurs outside the tube and housing and before the image receptor is called _____.

Back 112

Added Filtration

Front 113

The collimator device is considered ____filtration and average 1.0mm Al/eq (most of which comes from the silver on the mirror.)

Back 113

Added

Front 114

________is the most common filter material with a low atomic number of 13, which functions very well as a low-energy absorber.

Back 114

Aluminum

Front 115

_________ Filtration uses two or more materials that complement one another in their absorbing abilities.

Back 115

Compound

Front 116

Compound filters place the ____atomic number material closest to the tube and the ____ atomic number material closest to the patient. The final layer is usually aluminum (atomic

Back 116

Highest, lowest

Front 117

What filter is composed of Tin, Copper and aluminum?

Back 117

Thoreaus

Front 118

______ designed to solve a problem involving unequal subject densities by adding an absorber to compensate for unequal absorption with the subject.

Back 118

Compensation Filtration

Front 119

What are the two most popular Compensation Filters

Back 119

Wedge and Trough

Front 120

Wedge filter can be useful for ____________

Back 120

T-spine, feet and lower Ext.

Front 121

Trough filter con be useful for ____________

Back 121

CXR and shoulders

Front 122

_____ is equal to the sum of the inherent and added filtration.

Back 122

Total Filtration

Front 123

** The _________recommends minimum total filtration levels for diagnostic radiography

Back 123

National Council on Radiation Protection and Measurements (NCRP)

Front 124

Above 70 KVP, total filtration must be

Back 124

2.5mm aluminum

Front 125

Effect on Output reduces the patient exposure by ____low-energy photons from the primary beam. ____a portion of the useful beam

Back 125

Eliminating, removes

Front 126

when filtration is increased, to compensate for the loss of exposure, technical factors must be ____ to maintain the same image receptor exposure.

Back 126

increased