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36 Cards in this Set
- Front
- Back
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Which of the following groups of exposure factors will deliver the least amount of exposure to the patient?
A. 400 mA, 0.25 second, 100 kVp B. 600 mA, 0.33 second, 90 kVp C. 800 mA, 0.5 second, 80 kVp D. 800 mA, 1.0 second, 70 kVp |
A. 400 mA, 0.25 second, 100 kVp
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Acording to the NCRP, the annual occupational dose equivalent limit to the lens of the eye is
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150 mSv.
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If a patient received 2000 mrad during a 10-minute fluoroscopic examination, what was the dose rate?
A. 0.02 rad/min B. 0.2 rad/min C. 2.0 rad/min D. 20 rad/min |
B.
0.2 rad/min |
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Which of the following is considered the unit of exposure in air?
A. Roentgen (C/kg) B. Rad (Gy) C. Rem (Sv) D. RBE |
A. Roentgen (C/kg)
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What is the term used to describe x-ray photon interaction with matter and the transference of part of the photon's energy to matter?
A. Absorption B. Scattering C. Attenuation D. Divergence |
B. Scattering
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In 1906, Bergoniénd Tribondeau established their law, which states that cells are more radiosensitive if they
1. are young. 2. are stem cells. 3. have a low proliferation rate. |
1 and 2 only
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Patient exposure can be minimized by using which of the following?
1. Accurate positioning 2. High-kV, low-mAs factors 3. Rare earth screens |
1, 2, and 3
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The radiographer's radiation monitor report must include which of the following information?
1. Lifetime dose equivalent 2. Quarterly dose equivalent 3. Inception date |
1, 2, and 3
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Which of the following is (are) possible long-term somatic effects of radiation exposure?
1. Nausea and vomiting 2. Carcinogenesis 3. Leukemia |
2 and 3 only
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Which of the following dose-response curve characteristics represent genetic and some somatic responses to radiation?
1. Linear 2. Nonthreshold 3. Sigmoidal |
1 and 2 only
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If an individual receives 50 mR while standing 4 feet from a source of radiation for 2 minutes, which of the options listed below will most effectively reduce his or her radiation exposure to that source of radiation?
A. Standing 3 feet from the source for 2 minutes B. Standing 8 feet from the source for 2 minutes C. Standing 5 feet from the source for 1 minute D. Standing 6 feet from the source for 2 minutes |
B.
Standing 8 feet from the source for 2 minutes |
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In 1906, Bergoniénd Tribondeau theorized that undifferentiated cells are highly radiosensitive. Which of the following is (are) characteristic(s) of undifferentiated cells?
1. Young cells 2. Highly mitotic cells 3. Precursor cells |
1, 2, and 3
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Which of the following are radiation protection measures that are appropriate for mobile radiography?
1. The radiographer must be at least 6 feet from the patient and the x-ray tube during the exposure. 2. The radiographer must announce in a loud voice that an exposure is about to be made and wait for personnel, visitors, and patients to temporarily leave the area. 3. The radiographer must try to use the shortest practical SID. |
1 and 2 only
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Which of the following would most likely result in the greatest skin dose?
A. Short SID B. High kVp C. Increased filtration D. Increased mA |
A. Short SID
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Rank the following tissues into order (A–D) from lowest weighting factor (Wt) to highest weighting factor.
A. Breast B. Lung C. Bone marrow D. Skin |
D. Skin
A. Breast B. Lung C. Bone marrow |
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Which of the following are considered most radiosensitive?
A. Lymphocytes B. Ova C. Neurons D. Myocytes |
A. Lymphocytes
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The presence of ionizing radiation may be detected in which of the following ways?
1. Ionizing effect on air 2. Photographic effect on film emulsion 3. Fluorescent effect on certain crystals |
1, 2, and 3
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The photoelectric effect is an interaction between an x-ray photon and
A. an inner-shell electron. B. an outer-shell electron. C. a nucleus. D. another photon. |
A. an inner-shell electron.
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The control dosimeter that comes from the monitoring company should be
A. stored in a radiation-free area. B. kept in a designated control booth. C. kept in the film processing area. D. used as an extra badge for new personnel. |
A. stored in a radiation-free area.
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Which of the following are recommended for the pregnant radiographer?
1. Continue monthly dosimeter readings. 2. Wear a second dosimeter under the lead apron. 3. Wear two dosimeters and switch their position periodically. |
1 and 2 only
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The interaction between x-ray photons and tissue that is responsible for radiographic contrast but that also contributes significantly to patient dose is
A. the photoelectric effect. B. Compton scatter. C. coherent scatter. D. pair production. |
A. the photoelectric effect.
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In the production of characteristic radiation at the tungsten target, the incident electron
A. ejects an inner-shell tungsten electron. B. ejects an outer-shell tungsten electron. C. is deflected, with resulting energy loss. D. is deflected, with resulting energy increase. |
A. ejects an inner-shell tungsten electron.
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All of the following have an effect on patient dose except
A. inherent filtration. B. added filtration. C. SID. D. focal spot size. |
D. focal spot size.
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Stochastic effects of radiation are those that
1. have a threshold. 2. may be described as "all-or-nothing" effects. 3. are late effects. |
2 and 3 only
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Which of the following is (are) composed of nondividing, differentiated cells?
1. Neurons and neuroglia 2. Epithelial tissue 3. Lymphocytes |
1 only
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The exposure rate to a body 4 feet from a source of radiation is 16 R/hr. What distance from the source would be necessary to decrease the exposure to 6 R/hr?
A. 5 feet B. 7 feet C. 10 feet D. 14 feet |
B. 7 feet
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Which of the following illustrates the inverse square law?
1. Distance is a most effective protection from radiation. 2. Distance is a rather ineffective protection from radiation. 3. As distance from the radiation source decreases, radiation decreases. |
1 only
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Use your mouse to drag the following cells into order (A–D) from most radiosensitive to least radiosensitive.
B. Epithelial cells A. Immature spermatogonia C. Osteoblasts D. Muscle cells |
A:C:B:D.
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Sources of secondary radiation include
1. background radiation. 2. leakage radiation. 3. scattered radiation. |
2 and 3 only
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Which of the following contributes most to patient dose?
A. The photoelectric effect B. Compton scatter C. Classical scatter D. Thompson scatter |
A. The photoelectric effect
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Diagnostic x-radiation may be correctly described as
A. low energy, low LET. B. low energy, high LET. C. high energy, low LET. D. high energy, high LET. |
A. low energy, low LET.
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Medical and dental radiation accounts for what percentage of the general public's exposure to man-made radiation?
A. 10% B. 50% C. 75% D. 90% |
D.
90% |
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What is the established fetal dose-limit guideline for pregnant radiographers during the entire gestation period?
A. 0.1 rem B. 0.5 rem C. 5.0 rem D. 10 rem |
B.
0.5 rem |
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What is (are) the major effect(s) of deoxyribonucleic acid (DNA) irradiation?
1. Malignant disease 2. Chromosome aberration 3. Cell death |
1, 2, and 3
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How much protection is provided from a 75-kVp x-ray beam when using a 0.50-mm lead equivalent apron?
A. 51% B. 66% C. 88% D. 99% |
C. 88%
The 1.0-mm lead equivalent apron will provide close to 100% protection at most kVp levels, but it is rarely used because it weighs anywhere from 12 to 24 lb. A 0.25-mm lead equivalent apron will attenuate about 97% of a 50-kVp x-ray beam, 66% of a 75-kVp beam, and 51% of a 100-kVp beam. A 0.5-mm apron will attenuate about 99% of a 50-kVp beam, 88% of a 75-kVp beam, and 75% of a 100-kVp beam. |
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When an image intensifier's magnification mode is used,
1. output screen gain is increased. 2. resolution increases. 3. patient dose increases. |
2 and 3 only
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