RADS 2100 Mosby's Challenge #1

Describes changes in the x-ray beam as it travels through the patient

1. Attenuation:

a. Is radiation that emerges from the patient

b. Describes changes in the x-ray beam as it travels through the patient

c. Produces only scatter radiation

d. Occurs only at doses used in radiation therapy

Photoelectric

2. Which photon-tissue interaction makes radiography possible because of it's creation of contrast?

a. Compton

b. Coherent

c. Photoelectric

d. Pair production

Compton

3. Which photon-tissue interaction produces radiation that may expose others in the room during fluoroscopy?

a. Compton

b. Coherent

c. Photoelectric

d. Pair production

Gy a

4. The unit of radiation absorbed in air is the:

a. Sv

b. Gy a

c. Bq

d. Gy t

Becquerel

5. The unit of radioactivity is the:

a. Becquerel

b. Gray t

c. Sievert

d. Gray a

Sievert

6. The unit of effective dose is the:

a. Becquerel

b. Gray t

c. Sievert

d. Gray a

Varies for different types of radiation

7. Linear energy transfer:

a. Is the same for all types of radiation

b. Is the same for wave and particulate radiations

used in diagnosis and treatment

c. Occurs only during x-ray procedures

d. Varies for different types of radiation

Nuclear medicine

8. The unit of Bq would be used in what imaging modality?

a. Radiography

b. CT

c. MRI

d. Nuclear medicine

Dose-response curves

9. Graphs that show the relationship between radiation received and the organism's response are called:

a. Response curves

b. Exposure curves

c. Dose-response curves

d. Radiation-threshold curves

Artificially produced radiation

10. Medical x-rays are an example of:

a. Natural background radiation

b. Artificially produced radiation

c. Nonionizing radiation

d. Ionizing, natural background radiation

Threshold

11. Cataractogenesis does not occur at low levels of radiation exposure, it is best expressed by which of the following dose-response relationships?

a. Threshold

b. Nonthreshold

c. Low dose

d. Occupational dose

Stochastic effects

12. Increased dose equals increased probability of effects

best describes which of the following?

a. Stochastic effects

b. Deterministic effects

c. Direct effect

d. Indirect effect

220 mSv

13. The cumulative occupational exposure for a 22-year-old radiographer is:

a. 220 mSv

b. 22 mSv

c. 11 mSv

d. 110 mSv

1.0 mSv

14. The annual effective dose limit for the general public,

assuming frequent exposure, is:

a. 0.5 mSv

b. 500 mSv

c. 0.05 mSv

d. 1.0 mSv

1⁄32-inch Pb equivalent

15. The secondary protective barrier used in room shield-

ing must be at least how thick?

a. 1⁄32-inch Al equivalent

b. 1⁄16-inch Al equivalent

c. 1⁄16-inch Pb equivalent

d. 1⁄32-inch Pb equivalent

90-degree

16. The intensity of the scattered beam is 1⁄1000 the

intensity of the primary beam at a ________ angle 1 m from the patient.

a. 45-degree

b. 25-degree

c. 90-degree

d. 10-degree

20 Gray a

17. If the air kerma measured 6 feet from the x-ray table is 5 Gray a, what is the air kerma measured at a distance of 3 feet?

a. 20 Gray a

b. 10 Gray a

c. 1.25 Gray a

d. 2.5 Gray a

15 inches

18. The minimum source-to-skin distance for fixed fluoroscopes is:

a. 15 inches

b. 12 inches

c. 10 inches

d. 18 inches

deterministic

19. When increased dose equals increased severity of tissue reactions, this is called:

a. probalistic

b. stochastic

c. deterministic

d. mutagenic

oxygen enhancement ratio

20. Cells that are oxygenated are more susceptible to radiation damage, this describes:

a. Target theory

b. Direct effect

c. Doubling dose

d. oxygen enhancement ratio

0.25 mSv

21. The blood count is depressed after a whole-body dose

equivalent of at least how many mSv?

a. 10 mSv

b. 0.25 mSv

c. 5 mSv

d. 0.01 mSv

Free radicals

22. Highly reactive ions that have unpaired electrons in

the outer shell are called:

a. Electrified

b. Radiolytic

c. Hydrogen peroxide

d. Free radicals

DNA

23. The master molecule that directs cell activities is:

a. RNA

b. Hydrogen peroxide

c. A free radical

d. DNA

Mitosis

24. The process of somatic cell division is called:

a. Mitosis

b. Spermatogenesis

c. Organogenesis

d. Cytogenesis

Nothing

25. The most common effect from exposure to ionizing radiation is:

a. Mutations

b. Ionization of atoms in the cells

c. Cell death

d. Nothing

At doses of radiation much higher than doses used in radiography

26. Most radiation-induced damage to cells occurs:

a. At diagnostic levels of radiation

b. During fluoroscopy

c. At doses of radiation much higher than doses used in radiography

d. From background radiation

5 mSv

27. Radiation doses up to ________ are considered relatively low risk to the embryo and fetus.

a. 5 mSv

b. 10 mSv

c. 0.01 mSv

d. 0.20 mSv

ALARA

28. A concept of radiologic practice that encourages radiation users to adopt measures that keep the dose to the patient and themselves at minimum levels is called:

a. LET

b. RBE

c. MPD

d. ALARA

Nerve tissue

29. Which of the following is (are) relatively insensitive to radiation?

a. Nerve tissue

b. Reproductive cells

c. Epithelial tissue

d. Immature sperm cells

b

30. Somatic effects of radiation:

a. Are common

b. Are caused when a large dose of high-LET radiation is received by a large area of the body

c. Are caused after exposure of DNA

d. Include genetic mutations

Avoidance of repeat exposures

31. The best way to keep the radiation dose to the patient

low is:

a. Distance

b. Shielding

c. Time

d. Avoidance of repeat exposures

Ionization

32. X-rays may remove electrons from atoms in the body by a process called:

a. Electrification

b. Exposure

c. Ionization

d. Radicalizing

Unstable atoms

33. Ionization may cause:

a. Stable atoms

b. Production of high-energy x-rays

c. Formation of new molecules beneficial to the cell

d. Unstable atoms

Loss of function or abnormal function

34. Cell damage may be exhibited as:

a. Loss of function or abnormal function

b. Nothing

c. Enhanced function

Somatic

35. Damage to the cell being irradiated is called:

a. Genetic

b. Exposed cell

c. Somatic

d. Molecular

Genetic

36. Radiation effects that show up in the next generation are called:

a. Genetic

b. Exposed cell

c. Somatic

d. Molecular

Natural background

37. Radiation that is contained in the environment is called:

a. Man-made

b. Artificial

c. Natural background

d. Artificial background

50%

38. Background radiation is the source of approximately what percent of human exposure?

a. 95%

b. 82%

c. 50%

d. 35%

3.0 mSv

39. The annual effective dose per person from natural

background radiation is approximately:

a. 1.0 mSv

b. 3.0 mSv

c. 50 mSv

d. 9.0 mSv

Radon

40. The greatest source of natural background radiation

to humans is:

a. X-rays

b. Delta rays

c. Radon

d. Radium

CT

41. According to NCRP Report #160, the increase in total

exposure is primarily attributed to increased use of:

a. MRI

b. Diagnostic medical ultrasound

c. Fluoroscopy and interventional procedures

d. CT

Primary protective barrier

42. What barrier must be at least 1/16-inch lead equivalent?

a. Lead apron

b. Primary protective barrier

c. Bucky slot cover

d. Secondary protective barrier

24%

43. CT accounts for approximately what percent dose to the population (NCRP Report #160)?

a. 24%

b. 50%

c. 15%

d. 80%

Germ

44. Meiosis describes the process of division of what type of cells?

a. Somatic

b. Cancer

c. Muscle

d. Germ

Cumulative effective dose

45. What refers to the lifetime-accumulated occupational dose?

a. Annual accumulated effective dose

b. Cumulative effective dose

c. Common effective dose

d. Common medical effective dose

30

46. Exposure times longer than ____ minutes can lead to skin effects.

a.5

b. 10

c. 20

d. 30

Air kerma

47. What provides an approximate skin dose where the

x-ray beam is entering the patient?

a. Sievert

b. Becquerel

c. Air kerma

d. Effective dose

Air kerma

48. The preferred term for radiation exposure is:

a. Coulombs per kilogram

b. Gray

c. Sievert

d. Air kerma

NCRP reports

49. Effective dose limits may be found in what published material?

a. Dose limit reports

b. NCRP reports

c. Environment Protection Agency reports

d. Health and Human Services reports

By chance

50. Photon-cell interactions occur:

a. Predictably

b. By chance

c. Seldom

d. Only at high radiation doses

Atom

51. The smallest particle of an element that retains the characteristics of the element is a(n):

a. Element

b. Atom

c. Molecule

d. Neutron

The number of protons plus the number of neutrons

52. Atomic mass refers to:

a. The number of protons plus the number of neutrons

b. The number of electrons

c. The number of electron shells

d. The number of protons

Photons

53. X-rays travel as bundles of energy called:

a. Protons

b. Phasers

c. Particles

d. Photons

Amplitude

54. The height of a sine wave is called:

a. Wavelength

b. Altitude

c. Amplitude

d. Frequency

Autotransformer

55. The transformer that operates on the principle of self-induction is the:

a. Step-up transformer

b. Step-down transformer

c. Induction transformer

d. Autotransformer

1⁄1000 second

56. Electronic timers used in x-ray equipment allow for exposure times of:

a. 1⁄100 second

b. 1⁄1000 second

c.1 μs

d. There is no limit to how short the exposure can be

Automatic exposure control

57. To ensure consistency of radiographic quality from one exposure to the next, what device may be used?

a. Electronic timer

b. Automatic collimation

c. Automatic exposure control

d. Falling load generator

Falling load generator

58. An x-ray machine that uses a continually decreasing

mA for the shortest times possible uses a(n):

a. Ionization chamber

b. Phototimer

c. AEC

d. Falling load generator

Transformers

59. Devices in the x-ray circuit that operate on the principle of mutual induction are called:

a. Rectifiers

b. Generators

c. Timers

d. Transformers

Step-up

60. The high-voltage section of the x-ray circuit makes use of what type of transformer?

a. Step-up

b. Autotransformer

c. Step-down

d. Falling load

Rectifier

61. The device in the x-ray circuit that changes AC to DC is the:

a. Autotransformer

b. Step-up transformer

c. Rectifier

d. Falling load generator

Direct

62. What type of current is required for proper operation of the x-ray tube?

a. Direct

b. Falling load

c. Alternating

d. Fluctuating

Electron cloud

63. The result of thermionic emission is a(n):

a. Recoil electron

b. Electron cloud

c. Scattered photon

d. Characteristic photon

Cathode

64. The focusing cup is located at the:

a. Cathode

b. Anode

c. X-ray tube window

d. Control panel

Characteristic

65. An interaction that produces x-rays at the anode as a result of outer shell electrons filling holes in the K-shell is called:

a. Characteristic

b. Photoelectric

c. Compton

d. Brems

High-resolution monitor

66. In digital fluoroscopy, the image should be viewed on what device to take advantage of the digital capabilities?

a. Digital viewbox

b. High-resolution monitor

c. High-definition TV

d. Plasma TV

Postprocessing manipulation of the image

67. A primary advantage of digital fluoroscopy is:

a. Postprocessing manipulation of the image

b. No radiation dose to the patient

c. No fluoroscopist required

d. Lower cost

Analog-to-digital converter

68. In digital fluoroscopy and computed radiography, the energy must be changed to digital form by a(n):

a. Digital-to-analog converter

b. Flux capacitor

c. Analog-to-digital converter

d. DVD-ROM

b

69. An algorithm is:

a. A mathematical hypothesis used in imaging

b. A mathematical formula used to reconstruct the

image in digital imaging

c. An advanced imaging procedure

d. The mathematical basis for film-screen imaging

Voxel

70. In computed radiography, each pixel corresponds to a shade of gray representing an area in the patient known as a(n):

a. Pathology

b. Density

c. Voxel

d. Artifact

Adjusting the window level

71. Lightness and darkness of the image in computed radiography may be adjusted by:

a. Doubling the kVp

b. Adjusting the window level

c. Adjusting the window width

d. Using digital fluoroscopy

Midpoint of densities

72. The window level in computed radiography is the:

a. Area of the patient being irradiated

b. Amount of radiation needed to obtain the image

c. Midpoint of densities

d. Top of the midpoint of densities

Window width

73. Radiographic contrast in computed radiography may be adjusted by changing the:

a. Window level

b. Window width

c. Area of the patient being irradiated

d. Imaging plate

mAs

74. The amount of receptor exposure is controlled primarily by:

a. kVp

b. Focal spot size

c. AEC

d. mAs

Manifest image

75. The visible image may also be called the:

a. Manifest image

b. Image-in-waiting

c. Preprocessed image

d. Latent image

mAs

76. The quantity of x-rays produced is directly controlled by:

a. kVp

b. OID

c. SID

d. mAs

15% rule

77. The rule or law that governs changing technique using kVp is the:

a. Inverse square law

b. Density maintenance law

c. Reciprocity law

d. 15% rule

Receptor exposure is quadrupled

78. If SID is halved, what may be said about receptor exposure?

a. Receptor exposure doubles

b. Receptor exposure is reduced by half

c. Receptor exposure is reduced by one-half of the mAs

d. Receptor exposure is quadrupled

Magnification

79. Distortion that affects the size of the object as represented on the radiographic image is called:

a. Minification

b. Foreshortening

c. Elongation

d. Magnification

Elongation and foreshortening

80. Shape distortion may take the form of:

a. Magnification and minification

b. Size and shape distortion

c. Elongation and foreshortening

d. Magnification and elongation

Magnification

81. A longer than usual OID may cause:

a. Elongation

b. Foreshortening

c. Minification

d. Magnification

Every 24 hours

82. CR cassettes should be erased at least:

a. Every 24 hours

b. Every 48 hours

c. Every 3 months

d. Weekly

Grid ratio

83. The equation H/D describes:

a. Grid radius

b. Contrast

c. Grid ratio

d. Reciprocity law

Widens

84. If the exposure field is not accurately recognized, the histogram:

a. Narrows

b. Widens

c. Remains the same

Speed class

85. Noise increases with an increase in:

a. mAs

b. Speed class

c. SID

d. OID

Artificial increase in display contrast at an edge of the image

86. Edge enhancement provides:

a. Artificial increase in display contrast at an edge of the image

b. Artificial increase in display brightness at an edge of the image

c. Artificial increase in spatial resolution at an edge of the image

Upside down

87. Which of the following grid errors would result in

an image that shows normal exposure in the middle but decreased exposure on the sides and may follow removal and replacement of the grid?

a. Upside down

b. Off-level

c. Lateral decentering

d. Grid-focus decentering

Number of lead strips per inch or centimeter

88. Grid frequency is described as the:

a. Height of the lead strips divided by the distance between the lead strips

b. Distance between the lead strips divided by the height of the lead strips

c. Number of lead strips per inch or centimeter

d. SID at which the grid may be used

Very sensitive

89. When working with CR and DR, one must be aware that their response to scatter radiation is:

a. Very sensitive

b. Minimally sensitive

c. Irrelevant

In greater detail than on radiographers' monitors

90. The images on radiologists' monitors appear:

a. The same as on radiographers' monitors

b. In greater detail than on radiographers' monitors

c. In less detail than on radiographers' monitors

Inappropriate collimation

91. A histogram analysis error may be caused by:

a. Excessive mAs

b. Pixel unresponsiveness

c. Inappropriate collimation

d. Excessive kVp

Evenness in brightness

92. Smoothing provides:

a. Higher spatial resolution

b. Equalization

c. Evenness in brightness

d. Higher contrast resolution

Uniform processing codes

93. Consistency of image appearance is achieved through the use of:

a. Higher speed class

b. Uniform processing codes

c. More effective post processing

d. Lower exposure index numbers

c

94. Which of the following sets of exposure factors would produce an image with the poorest spatial resolution?

a. 60 mAs, 80 kVp, 40-inch SID, 4-inch OID

b. 30 mAs, 92 kVp, 40-inch SID, 4-inch OID

c. 120 mAs, 92 kVp, 20-inch SID, 4-inch OID

d. 15 mAs, 100 kVp, 40-inch SID, 4-inch OID

a

95. Which of the following sets of exposure factors would produce an image with the best spatial resolution?

a. 60 mAs, 80 kVp, 72-inch SID, 4-inch OID

b. 30 mAs, 92 kVp, 40-inch SID, 4-inch OID

c. 120 mAs, 92 kVp, 20-inch SID, 4-inch OID

d. 15 mAs, 100 kVp, 40-inch SID, 4-inch OID

Shorter scale of contrast

96. Beam restriction has the following effect on contrast:

a. Decreases contrast

b. Longer scale of contrast

c. Shorter scale of contrast

d. No effect on contrast

Short wavelengths

97. As kVp increases, there is an increased production of:

a. Long wavelengths

b. Low-energy waves

c. Short wavelengths

d. Electrons

Direct, although not proportional

98. The relationship between kVp and receptor exposure is:

a. Indirect

b. Directly proportional

c. Direct, although not proportional

d. Inverse

Focused

99. Grids that have strips angled to coincide with divergence of the x-ray beam are called:

a. Parallel

b. Crosshatch

c. Focused

d. Rhombic

The image is determined by the total exposure

100. In digital imaging, the radiographer must be aware that:

a. mAs is the primary controlling factor

b. The image is determined by the total exposure

c. Speed class is the primary controlling factor

d. kVp is the primary controlling factor