2015 FALL FINAL!!!!!<3 Flashcards Preview

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Flashcards in 2015 FALL FINAL!!!!!<3 Deck (86)
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1
Q

Negatively charged electrode. Coiled wire that is a source of electrons

A

Cathode/Filament

2
Q

Surrounds the cathode/filament to focus stream of electrons onto the focal track of the anode

A

Focusing Cup

3
Q

2 filaments and 1 anode

A

dual focusing cup

4
Q

positively charged electrode. Stationary or rotating.

A

Anode

5
Q

A rotating anode can rotate at

A

3,000-10,000 RPM

6
Q

This can withstand a great amount of heat and is a big makeup of the anode

A

Tungsten

7
Q
  1. A rotating motor consists of ______ & ______

2. And these make up a ____ motor. Speeds can change.

A
  1. rotor and stator

2. induction

8
Q

Moving energy

A

Kinetic energy

9
Q

When electrons strike the anode, Kinetic Energy is converted to __1__ heat and __2__ energy

A
  1. 99%

2. 1%

10
Q

X-ray tube is made of _______ because it can withstand a great amount of heat.

A

pyrex glass

11
Q

The xray tube is ______ to provide unobstructed path for electrons

A

vacuumed

12
Q

The xray tube is insulated with

A

lead and oil

13
Q

Leakage radiation cannot exceed

A

100mR/hr @ a distance of 1 meter

14
Q

German word for braking

A

Brehmsstrahlung

15
Q

Forms 85-90% of the beam. Occurs when the electrons rapidly decelerate and loop around nucleus on surface of anode.

A

Brehmsstrahlung

16
Q

10-15% of the beam. Occurs when electrons on face of anode drop to fill hole in inner shells

A

Characteristic

17
Q

used in fluro, positive pressure switch.

A

“Deadman Switch”

18
Q

Tube current displays only during ______

A

exposure

19
Q

Quantity, number, amount

A

controlled mAs

20
Q

Quality, energy, penetrating ability

A

controlled by kV

21
Q

least ripple 3-5% and is most efficient

A

High frequency transformer

22
Q

No practical amount of __1__ can ever compensate for inadequate __2__

A
  1. mA

2. kVp

23
Q

Recorded detail (spatial resolution) is controlled by 3 geometric factors

A
  1. focal spot size
  2. OID
  3. SID
24
Q

projected or effective focal spot is smaller than the AFS

A

Blooming

25
Q

over 100 mAs, use _____

A

large FS

26
Q

The steeper the anode, the _____ the FS

A

smaller

27
Q

Intensity of beam is greater on the cathode side of the tube

A

Anode heel effect

“FAT CAT”

28
Q

Ways to enhance AHE (3 ways)

A
  1. steep anode
  2. large IR
  3. short SID
29
Q

Main purpose of the filtration

A

to decrease patients skin dose

30
Q

If a tube operates at __1__, you must have __2__ filtration

A
  1. 70 kVp

2. 2.5 mm Al

31
Q

amount of metal that cuts intensity to half its initial output.

A

Half Value Layer (HVL)

*Thicker HVL=stronger beam

32
Q

thick part of filter at thin part of anatomy

A

wedge filter

33
Q

Cut SID in half

A

4x greater radiation intensity

34
Q

Double SID

A

1/4 radiation intensity

35
Q

attenuation = _______ + _______

A

absorption + scatter

36
Q

total absorption of incoming photon

A

photoelectric effect

37
Q

xray gives up all of it’s energy-knocks out an inner shell electron

A

Photoelectron

38
Q

released as electrons drop down to fill holes in shells.

A

Characteristic radiation

39
Q

White or Clear on radiograph

A

photoelectric effect/characteristic radiation

40
Q

less than 30 kV (not in diagnostic)-TOO LOW

A

Classical/Coherent/Unmodified/White Scatter

41
Q

Modified scatter. Wray gives up some but not all of it’s energy to knock out an outer shell electron.

A

Compton

42
Q

Compton makes it’s presence known through

A

SCATTER

43
Q

Scatter is _____ on the radiograph

A

GRAY

44
Q

Are Pair Production and Photodisintegration in diagnostic?

A

No, too high

45
Q

when xrays pass through without interacting with the atoms in the body. Shows up black

A

Remnant/Transmission/Exit Radiation

46
Q

picture element that makes up the Matrix

A

pixel

47
Q

larger matrix & greater number of pixels=

A

improved spatial resolution

48
Q

Increasing pixel density and decreasing pixel pitch ________ spatial resolution

A

INCREASES

49
Q

A. OD of 1=
B. OD of 2=
C. OD of 3=

A

A. 1/10
B. 1/100
C. 1/1000

COUNT THE ZEROS

50
Q

Density (Screen Film)=

A

Brightness (Digital)

51
Q

Recorded detail (Screen Film)=

A

Spatial Resolution (Digital)

52
Q

Contrast (Screen Film)=

A

Grayscale/dynamic range (Digital)

53
Q

utilizes a plate that is put in a reader to retrieve image

A

CR

54
Q

utilizes a digital plate or digital bucky that sends image directly to computer

A

DR

55
Q

Main advantage of CR/DR

A

Post processing (window and leveling)

56
Q
  1. overall darkness on radiograph

2. controlled by

A
  1. Density

2. mAs

57
Q

To double density you must…

A

Double mAs

58
Q

To cut density in half you must…

A

cut mAs in half

59
Q

kVp controls _________

A

SCATTER

60
Q

Scatter is _______

A

DENSITY

61
Q

Above 90 kVp:

if you add 15 kV, you must ______

A

mAs in half

62
Q

Above 90 kVp:

if you take away 15 kV, you must ____

A

Double mAs

63
Q

Below 90 kVp:

if you add 10 kVp, you must

A

cut mAs in half

64
Q

Below 90 kVp:

If you subtract 10 kVp, you must _______

A

double mAs

65
Q

As collimation decreases then density __1__. As collimation increases then density __2__.

A
  1. Increases (b/c larger field size)

2. Decreases (smaller field size)

66
Q

part density and IR density are _____ proportional

A

inversely

67
Q

Automatic Processor

A

developer, fixer, washer, dryer

90 seconds to process film

68
Q

Main controlling factor of contrast

A

kV

69
Q
High kV= 
\_\_1\_\_ scale 
\_\_2\_\_ contrast
\_\_3\_\_ latitude
\_\_4\_\_ scatter
\_\_5\_\_ penetration
\_\_6\_\_ colors
A
  1. long
  2. low
  3. wide
  4. increased
  5. increased
  6. many
70
Q

Low kV=

  1. scale
  2. contrast
  3. colors
  4. latitude
  5. scatter
  6. penetration
A
  1. short
  2. high
  3. few
  4. narrow
  5. decreased
  6. decreased
71
Q

increased grid ratio = ______ contrast

A

increased

72
Q

increase collimation= ________ contrast

A

increased

73
Q

First step in protection

A

OPTIMUM COLLIMATION

74
Q
T
B
M
F
G
A

Hardest to penetrate to easiest

teeth, bone, muscle, fat, gas

75
Q

Contrast medias:
A. Adds density
B. Takes away density

A

A. Positive (ex: barium and iodine)

B. Negative (air and CO2)

76
Q

Additive pathology (ex: edema, atelectasis)=_____ kVp

A

increase

77
Q

destructive pathology (ex: emphysema, osteoporosis)=_______ kVp

A

decrease

78
Q

Three ways to overcome motion

A
  1. clear instructions
  2. Immobilization devices
  3. short exposure time
79
Q

Magnification is AKA

A

size distortion

80
Q

Increase SID and Decrease OID to prevent

A

size distortion (AKA magnification)

81
Q

Shape distortion is AKA

A

true distortion

82
Q

This is caused by mal-alignment of tube, part, and/or IR. Usually elongated or foreshortening. Can be done accidently or on purpose

A

Shape distortion

AKA true distortion

83
Q

if “S” number is too high then the IR is __1__ and image has excessive __2__.

if “S” number is too low then the IR is __3__ and patient maybe ultimately __4__ due to __5__.

A
  1. underexposed
  2. Quantum Mottle/Noise
  3. Overexposed
  4. overdosed
  5. dose creep
84
Q

Invisible image

A

Latent

85
Q

Visible image

A

Manifest

86
Q

Film Screen»Digital Term

  1. Density/Receptor Exposure
  2. Contrast
  3. Recorded Detail
A
  1. Brightness
  2. Grayscale/dynamic range
  3. spatial resolution