Exam 3 Radiobiology Flashcards
*What is the term for the proportional amount of time during which the x-ray beam is on and directed toward a particular protective barrier.
A. occupancy factor
B. workload factor
C. distance factor
D. Use factor
D. use factor
*Patient dose from diagnostic x-rays is most often reported in _____. a. bone marrow dose b. gonadal dose c. entrance skin exposure d. none of the above
c. entrance skin exposure
If the radiographic technique for a KUB calls for 40 mAs, what is the ESE when the output intensity is 0.075 mGy/mAs? a. 0.40 mGy b. 0.475 mGy c. 3 mGy d. 30 mGy
c. 3 mGy
For the average fluoroscopy exam the ESE is a. 40 mGy/min b. 80 mGy/min c. 400 mGy/hr d. 250 mGy/hr
a. 40 mGy/min
The radiation dose monitor most frequently used to measure patient exposure is the _____. a. film badge b. G-M meter c. nomogram d. thermoluminescent dosimeter
d. thermoluminescent dosimeter
*The approximate average bone marrow dose to the population of the United States is _____ mGy/yr. a. 0.01 b. 0.1 c. 1 d. 10
c. 1
The genetically significant dose for the general public is important because of the risk of _____. a. increasing skin cancer b. effects on the gene pool c. damage to the fetus d. all of the above
b. effects on the gene pool
CT is considered a low-dose procedure. a. True b. False
false
The period of major organogenesis is during the _____ of pregnancy. a. first 2 weeks b. second to tenth week c. 2nd trimester d. 3rd trimester
b. second to tenth week
Patient dose can be reduced by using _____. I. faster screens II. higher kVp III. increased distance a. I only b. II only c. I & II d. I, II, & III
c. I & II
Breast dose from a scoliosis exam can be reduced by using the _____. I. AP projection II. PA projection III. lead shielding a. I b. II c. I & III d. II & III
d. II & III
The dose in CT is lower if the multislice number is higher. a. True b. False
a. True
Which of the following instruments is called a cutie pie? A. Geiger Muller detector B. Ionization chamber type survey meter C. Optically stimulated luminescence meter D. Proportional counter
B. Ionization chamber type survey meter
What is the purpose of radiographic beam filtration A. to decrease beam hardness, thereby reducing patient skin dose and the dose to superficial areas B. To increase beam hardness, thereby reducing the radiation received by the patients and the dose to superficial areas
B. To increase beam hardness, thereby reducing the radiation received by the patients and the dose to superficial areas
The maximum weekly permitted dose for a controlled area must bot exceed: A. 1000 microsievert (100mrem) B. 100 microsievert (10mrem) C. 20 microsievert D. 2 microsivert
A. 1000 microsievert (100mrem)
Exposure rate is 10R/ minute at 40 inches, what will be the rate at 20 inches? A. 20 R/ minute B. 40 R/ minute C. 60 R/ minute D. 80 R/minuste
B. 40 R/ minute
*The output intensities of reproduced exposures should not vary more than _____% from each other. a. 5 b. 10 c. 15 d. 20
a. 5
*Measuring the relationship between the output intensities of adjacent mA stations is a test of _____. a. HVL b. beam limitation c. reproducibility d. linearity
d. linearity
*The source-to-skin distance must be no less than _____ cm on stationary fluoroscopes. a. 30 b. 38 c. 42 d. 48
b. 38
*The _____ is the primary protective barrier for the fluoroscopic x-ray tube. a. ceiling b. floor c. image intensifier d. table top
c. image intensifier
A fluoroscopy system with automatic collimation must provide an unexposed border around the image at _____ above the table top. a. all heights b. 35 cm c. 25 cm d. 18 cm
a. all heights
*The fluoroscopic exposure control switch is always a(n) _____ type. a. rheostat b. automatic c. deadman d. on-off
c. deadman
*The bucky slot opening in the side of the table must be automatically covered with _____ mm Pb during fluoroscopy. a. 1.25 b. 1.0 c. 0.5 d. 0.25
d. 0.25
*A cumulative timer is designed to _____ of fluoroscopy beam-on time. a. make the radiologist aware b. turn off the radiation every 5 minutes c. prevent more than 10 minutes d. shut down the system after 15 minutes
a. make the radiologist aware
*A controlled area is one occupied primarily by _____. a. radiology personnel b. patients c. the general public d. both A and B
d. both A and B
For exposure to 1 rad of each of the following ionizing radiations, which would result in the greatest dose to the individual? A. external source of 1 Mev x-rays B. external source of diagnostic x-rays C. internal source of alpha particles D. external source of beta particle
C. internal source of alpha particles
Biologic material is lest radiosentive to irradiation under which of the following condition? A. Anoxic B. Hypoxic C. Oxygenated D. Deoxygenated
A. Anoxic
How far must a radiographer stand back during a mobile radiographic exposure? a. 1 meter b. 2 meters c. 3 meters d. 4 meters
b. 2 meters
A quantity that reflects both dose and volume of tissue irradiated is the___ A. estimated skin exposure B. dose area product C. proportional region D. Rem
B. dose area product
Exposure is measured by multiplying _____ by _____. a. shielding thickness, exposure time b. exposure rate, exposure time c. exposure rate, shielding thickness d. exposure time, distance
b. exposure rate, exposure time
If a technologist is exposed to 4 mGyt/hr for 45 minutes during a fluoroscopy exam, what will be her total exposure? a. 1 mGyt b. 2 mGyt c. 3 mGyt d. 4 mGyt
c. 3 mGyt
When using the inverse square law during fluoroscopy, the patient should be considered a(n) _____ source of radiation. a. Area b. Linear c. Round d. Point
d. Point
If a technologist is receiving 2 mGyt/hr standing 1 foot from the patient during fluoroscopy, what is his rate of exposure when he steps back to a distance of 2 feet from the patient? a. 0.50 mGyt/hr b. 0.74 mGyt/hr c. 1 mGyt/hr d. 1.75 mGyt/hr
a. 0.50 mGyt/hr
A tenth-value layer is equal to _____ half-value layers. a. 1.2 b. 3.3 c. 5.5 d. 10.0
b. 3.3
If the HVL in a radiology department is 0.25 mm Pb, then how thick should a shield be to reduce the technologists’ exposure to one fourth the incident scatter? a. 0.125 mm Pb b. 0.25 mm Pb c. 0.5 mm Pb d. 1.0 mm Pb
c. 0.5 mm Pb
Dose limits are based on a _____ dose-response relationship to radiation. a. nonlinear, nonthreshold b. linear, nonthreshold c. linear, threshold d. nonlinear, threshold
b. linear, nonthreshold
A secondary barrier is designed to absorb___ radiation A. leakage B. scattered C. primary D. Both A and B
D. Both A and B
What is the minimum requirement for filtration on x-ray equipment operating above 70 kVp? a. 1.5 mm Al equivalent b. 2.0 mm Al equivalent c. 2.5 mm Al equivalent d. 3.5 mm Al equivalent
c. 2.5 mm Al equivalent
The intensity of scatter radiation 1 meter from the patient is approximately _____ of the intensity of the incident beam at the patient. a. 0.01% b. 0.1% c. 10% d. 50%
b. 0.1%
Radiation interaction with macromolecules can result in disruption of a single chemical bond producing___
A. main chain scission
B. cross linking
C. point lessions
D. macromolecular synthesis
C. point lessions
An uncharge molecule that contains a sinlge unpaired to the outer shell is known as:
A. point mutation
B. radiolysis
C. cross linking
D. free radical
D. free radical
The principle effect of radiation on human is from___
a. indirect
B. direct
a. indirect
During the crosslinking the viscosity of the molecular solution is:
A. increased
B. decrease
C. no change
A. increased
Which of the folowing particles is consiered to be a form of antimatter?
A. electron
B. positron
C. x-ray photon
D. scatter x-ray photon
B. positron
which of the following interactions results in the conversion of matter
A. classical scattering
B. photoelectric
C. modified scattering
B. photoelectric
Which of the following is a measure of the rate of energy loss along an ionizing particle?
a. scintillation scatter
b. linear energy transfer
C. ionization
b. linear energy transfer
Which of the following would posses the highest LET?
A. Alpha
B. Beta
C. Gamma
D. x-rays
A. Alpha
Which of the following types would be the least radiosensitive?
A. bone marrow
B. skin
C. kidney
D. muscle
D. muscle
The ___ are the most radiosensitive
a. thrombocytes
b. lymphocytes
c. granulocytes
d. neurocytes
b. lymphocytes
A tungsten atom posses a K shel binding energy of 69.5 kev and a L shell of 12.1 kev. During characteristic x-ray production, a transition of the L shell electron to a vacated K shell would result in production of a characteristic x-ray an energy of:
A. 81.6 kev
B. 69.5 kev
C. 57.4 kev
D. 12.1 kev
C. 57.4 kev
Which of the following are the by products of photoelectric absorption?
- photoelectron
- characteristic x-ray
- ionized atom
A. 1 and 2
B. 1&3
C. 1,2,3
C. 1,2,3
Which of the following are not common in diagnostic radiography?
a. coherent
b. photoelectric
C. pair production
d. photodisinteragtion
e. Both c and d
e. Both c and d
In which of the following interactions the incoming photons do not transfer energy surrounding atoms?
a. coherent
b. photoelectric
c. pair production
a. coherent
In which of the following the incoming photons interacts with the outer shell and ejects it from its orbit?
a. coherent
b compton
c. photoelectric
b compton
In which of the following interactions the incoming photon uses all of its energy to eject an electron?
a. compton
b. coherent
c. photoelectric
c. photoelectric
Which of the following is a wide angle scatter?
a. coherent
b. compton
c. pair production
b. compton
Most of the back scatter in diagnostic radiography is caused by
A. compton scatter
B. Annihilation
C. coherent
A. compton scatter
Which of the following interactions causes anti-matter reactions?
a. compton
b. coherent
c. pair production
c. pair production
To cause an antimatter reaction the incoming photon must posses a minimum energy of
A. 1.02 kev
B. 1.02 mev
C. 0.51 kev
D. 0.51mev
B. 1.02 mev
Which of the following interactions causes radioactive decay?
A. pair production
B. photodistergration
C. compton
B. photodistergration
Which of the following interaction is responsible for most of the scatter radiation recieved by radiologic technologist?
A. coherent
B. compton
C. pair production
B. compton
Proliferation of the genetic cell is known as:
a. mitosis
b. meiosis
c. photodisintergration
D
b. meiosis
Identify the correct order of various stages of cell proliferation as they occur in our body:
prophase, metaphase, anaphase, telephase
Radiation induced chromosome damage is analyzed during___
a. metaphase
b. anaphase
c. prophase
a. metaphase
Which of the following act as a communication channels in human cell?
A. erthyroblast
B. osteoblast
C. nerve cells
D. lymphocytes
B. osteoblast
Which of the following is highly sensitive to radiation?
a. stem cell
b. precursor cell
c. undifferentiated cells
d. all of the above
d. all of the above
The LET of diagnostic x-ray is approximately
a. 1.02 mev/micrometer
b. 0.51 mev micrometer
c. 3 kev/ micometer
c. 3 kev/ micometer
Which of the following causes the least effect to patients?
a. protraction
b. fractionation
b. fractionation
The ration of the dose of standard radiation necessary to produce a given effect to the dose of test radiation necessary to produce the same effect is known as:
A. LET
B. RBE
C. OER
B. RBE
OER and LET are
directly proportionate
indirectly proptionate
indirectly proptionate
Genetic effects are__
a. stochastic
B. nonstochastic
c. deterministic
a. stochastic
Radiation induced genetic damage follows a
linear nonthreshold relationship
Radiation induced cancer, leukimia and genetic effects follow a
linear nonthreshold relationship
For diagnostic x-ray personnel, the highest occupational exposure occurs during _____ exams.
I. fluoroscopy
II. mobile radiography
III. spinal
IV. dental
a. I & II
b. I & III
c. I & IV
d. III & IV
a. I & II
Personnel working in interventional radiography should be provided with _____.
a. collar monitoring only
b. waist monitoring under the apron
c. extremity monitoring
d. gonadal monitoring
c. extremity monitoring
The lens of the eye should never receive more than _____ per year.
a. 10 mSv (1 rem)
b. 150 mSv (15 rem)
c. 50 mSv (5 rem)
d. 500 mSv (50 rem)
b. 150 mSv (15 rem)
Dose limits are described as _____.
a. exposure dose
b. threshold dose
c. effective dose
d. dose equivalent
c. effective dose
Occupational dose is described as _____.
a. exposure dose
b. threshold dose
c. effective dose
d. dose equivalent
d. dose equivalent
The tissue weighting factor has a higher value for tissues with more _____.
a. density
b. thickness
c. radiosensitivity
d. radioresistance
c. radiosensitivity
For nursing personnel present during mobile x-ray imaging, a personnel monitoring device is required _____.
a. at all times
b. not at all
c. during exposures
d. only for C-arms
b. not at all
The dose limit to the extremities is _____.
a. 5000 mSv/yr (500 rem/yr)
b. 500 mSv/yr (50 rem/yr)
c. 50 mSv/yr (5 rem/yr)
d. 5 mSv/yr (50 rem/yr)
b. 500 mSv/yr (50 rem/yr)
The lowest occupational exposure of diagnostic x-ray personnel occurs during _____.
a. CT
b. mammography
c. fluoroscopy
d. both A and B
d. both A and B
The dose limit to the general public is _____.
a. 1 mSv/yr (100 mrem/yr)
b. 10 mSv/yr (1000 mrem/yr)
c. 100 mSv/yr (10 rem/yr)
d. 1 Sv/yr (100 rem/yr)
a. 1 mSv/yr (100 mrem/yr)
Occupational radiation monitoring is required if the individual may get _____ of the recommended dose limit.
a. 100%
b. 50%
c. 25%
d. 10%
d. 10%
Optically stimulated luminescent (OSL) monitors are superior to the thermoluminescent dosimeters in that they are _____.
a. lighter weight
b. less sensitive to moisture
c. more sensitive to low exposure
d. both A and B
c. more sensitive to low exposure
During fluoroscopy the exposure to the collar is _____ times greater than exposure to the trunk of the body under a protective apron.
a. 50
b. 20
c. 10
d. 2
b. 20
A protective apron with a thickness of 0.25 mm lead equivalent is the minimum required.
a. True
b. False
a. True
The preferred way to hold patients who are unable to support themselves is to use a _____.
a. restraining device
b. family member
c. nurse
d. technologist
a. restraining device
The dose limit for a technologist during pregnancy is _____.
a. 0.05 mSv/mo (5 mrem/mo).
b. 0.5 mSv/mo (50 mrem/mo).
c. 5 mSv/mo (500 mrem/mo).
d. 50 mSv/mo (5000 mrem/mo).
b. 0.5 mSv/mo (50 mrem/mo).
