Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
64 Cards in this Set
- Front
- Back
1. Attenuation
|
Describes changes in the xray beam as it travels through the patient.
|
|
2. Which photon-tissue interaction makes radiography possible because of its creation of contrast
|
Photoelectric
|
|
3. Which photon tissue interaction produces radiation that may expose others in the room during fluoscopy
|
Compton
|
|
The traditional unit of absorbed dose it the
|
RAD
|
|
The traditional unit of activity is the
|
Curie
|
|
6. Measurement of positive and negative particles created when radiation ionizes atoms in the air helps define the
|
Roentgen
|
|
7. Linear Energy transfer
|
varies for different types of radiation
|
|
8. The unit of curie would be used for what imaging modality?
|
Nuclear medicine
|
|
9. Graphs that demonstrate the relationship between radiation received and the organism's response are called
|
Dose response curves
|
|
10. Medical x-rays are an example of
|
Artifically produced radiation
|
|
11. Cataractogenesis does NOT occur at low levels of radiation exposure. Therefore it is best expressed by which dose response relationship?
|
Threshold
|
|
12. Increased dose equals increased probability of effects best describes
|
Stochastic effects
|
|
13. The cumulative occupational exposure for a 22 year old radioagraphyer is
|
22 rem
|
|
14. The annual effective dose limit for the general public, assuming frequent exposure is
|
0.1 rem
|
|
15. The secondary protective barrier used in room shielding must be at least how thick?
|
1/32 inch Pb equivalent
|
|
16. The intensity of the scattered beam is 1/1000 the intensity of the primary beam at a _______ angle 1 meter from the patient.
|
90 degrees
|
|
17. If the radiation dose 6 feet from the xray table is 5 R, what is the dose at a distance of 3 feet?
|
20 R
|
|
18. The minimum source-to-skin distance for fixed fluoroscopes is
|
15 inches
|
|
19. The use of gonadal shielding on female patients may reduce gonad dose by up to:
|
50%
|
|
20. Cells that are oxygenated are more susceptible to radiation damage. This describes
|
Oxygenation enhancement ratio
|
|
21. The blood count is depressed following a whole body dose equivalent of at least how many rads?
|
25
|
|
22. Highly reactive ions that have unpaired electrons in the outer shell are called?
|
Free radicals
|
|
23. The master molecule that directs cell activities is
|
DNA
|
|
24. The process of somatic cell division is
|
Mitosis
|
|
25. The most common effect from exposure to ionizing radtion is
|
nothing
|
|
26. Most radiation-induced damage to cells occurs
|
at doses of radiation much higher than that ued in radiography
|
|
27. Radiation doses up to _____ are considered low risk to the embryo-fetus.
|
15 - 20 rads
|
|
28. A concept of radiologic practice that encourages radiation users to adopt measures that keep the dose to the patient and themselves at the minimum.
|
ALARA
|
|
29. Which of the following is(are) relatively insensitive to radiation?
|
Nerve tissue
|
|
30. Somatic effects of radiation are caused when
|
a large dose of high-LET radiation is received by a large area of the body.
|
|
31. The best way to keep radiation dose to the patient low is
|
Avoiding repeat exposures
|
|
32. Xrays may remove electrons from atoms in the body by a process called
|
Ionization
|
|
33. Ionization may cause
|
Unstable atoms
|
|
34. Cell damage may be exhibited as
|
loss of function or abnormal function
|
|
35. Damage to the cell being irradiated is called ...
|
Somatic
|
|
36. Radiation effects that show up in the next generation are called ...
|
Genetic
|
|
37. Radiation that is contained in the environment is called
|
Natural Background
|
|
38. Background Radiation is the source of what percent of human exposure?
|
82%
|
|
39. The annual effective dose per person from natural background radiation is approxmiately _____.
|
295 mrem
|
|
40. The greatest source of natural background radiation to humans is _______.
|
Radon
|
|
41. The smallest parictle of an element that reatins the characteristics of the element is an _____.
|
Atom
|
|
42. Atomic Mass refers to:
|
The number of neutrons .0
the number of protons plus the number of neutrons |
|
43. Xrays trave as budnles of energy called:
|
Photons
|
|
44. The height of a sine wave is called:
|
Amplitude
|
|
45. The number of xray waves passing a given point per unit time is called:
|
Frequency
|
|
46. The transformer that operates on the principle of self - induction is the:
|
Autotransformer
|
|
47. Electronic timers used in xray equipment allow for exposure times as low as:
|
1/1000 second
|
|
48. To ensure consistency of radiographic quality from one exposure to the next, what device may be used?
|
Automatic Exposure Control
|
|
49. What happens when a predetermined level of ionization is reached in the ionization chamber?
|
The exposure is terminated
|
|
50. An x-ray machine that uses a continually decreasing mA for the shortest times possible uses a(n):
|
Falling load generator
|
|
51: An x-ray machine that makes maxiumu use of heat loading potential uses a(n):
|
Falling Load generator
|
|
52. Devices in the x-ray circuit that operate on the principle of mutual induction are called:
|
Transformers
|
|
53. The high-voltage section of the x-ray circuit makes use of what type of transformer?
|
Step-up
|
|
54. The device in the x-ray circuit that changes AC to DC is the _____.
|
Rectifier
|
|
55. What type of current is required for proper operation of the x-ray tube?
|
Direct
|
|
56. Modern Rectifiers are made of ________.
|
Silicon-based semiconductors.
|
|
57. The result of thermionic emission is a(n) _________.
|
Electron Cloud
|
|
58. The focusing cup is located at the _______.
|
Cathode
|
|
59. An interaction that produces x-rays at the anode as a result of outer-shell electrons filling holes in the K-shell is called:
|
Characteristic
|
|
60. When a quality control test is performed to ensure that adjacent mA stations are accurate, the results must be within this amount of one another.
|
10%
|
|
61. When a quality control test is performed to ensure that the same exposure factors produce consistent x-ray output, successive epxures must be within this amount of one another
|
5%
|
|
62. When a quality control test is performed to ensure that the collimator is providing appropriate radiation protection, the result must be within this amount.
|
2%
|
|
63. When a quality control test is performed to ensure that the penetrating ab ility of the xray beam is accurate, the result must be within this amount of the control panel setting:
|
4
|
|
64. The accuracy of collimation of a 60 inch SID must be
|
+/-1.2 inches
|