Which of the following terms could be defined as the instantaneous production of light caused by an interaction between a type of energy and some element or compound?
Erythema, an early sign of biological damage due to x-ray exposure is:
a. reddening of he skin
b. malignant tumor
c. chromosomal change
d. one of the most serious effects of x-ray exposure
Which of the following is correct description of the relationship between the wavelength and the frequency of the x-ray photon?
a. wavelength and frequency are directly proportional
b. wavelength and frequency are inversely related by the square root of lambda
c. frequency and wavelength are inversely related
d. wavelength and frequency have no relationship to each other
The speed of light:
a. 3 x 10^8 meters per second
b. 3 x 10^8 miles per second
c. 186,000 miles per second
d. a and c
The _____ is the portion of the x-ray tube that contains the filament.
d. rotating disk
What is the name of the exact area on the anode that is struck by the electron beam?
a. focal spot
b. focal point
d. any of the above
What is an acceptable level of leakage from the tube housing?
a. 100 mR/hr measured 6 ft away
b. 10 mR/hr measured 1 ft away
c. 1000 R/hr measured at a distance of 4 meters
d. 100 mR/hr measured at distance of 1 meter
________ is the boiling off of electrons from the filament when current is applied.
mA is the measure of _____ that flows from the cathode to the anode.
a. filament current
b. tube current
c. space charge
d. thermionic emission
Increasing the kVp will do which of the following?
a. decrease the tube current
b. increase the speed of electrons
c. increase the penetrability of the beam
d. b and c
The filtration of the x-ray beam results in:
a. increased beam quantity
b. increased beam quality
c. lower average energy photons
d. b and c
The amt of filtration required to reduce the exposure of the beam to half of its original intensity is defined as:
a. wedge filtration
c. mAs compensator
d. mA linearity
_____ results in the process of the image formation, whereby the x-ray beam interacts with the anatomic tissue and a portion of the beam strikes the image receptor.
______ is loss of some of the energy from the x-ray beam as it passes through the tissue being imaged
True/False. The photoelectric effect is dependent on both the energy of the x-ray photon and the composition of the anatomic tissue.
When the x-ray photon travels completely through the part, that activity is called:
The xray beam that leaves the patient in the direction of the image receptor is often referred to as:
a. primary radiation
b. exit radiation
c. absorbed radiation
d. scattered radiation
Unwanted density on the radiograph due to scatter radiation is called:
_____ image occurs first on the image receptor, and the _____ iamge occurs following proper image development/processing.
a. manifest, latent
b. invisible, latent
c. visible, manifest
d. latent, manifest
At higher kV, _____ photon interactions occur, resulting in _____ transmission
a. more, increased
b. more, less
c. fewer, increased
d. fewer, less
Imaging of the movement of internal structures is known as:
a. image intensification
b. digital imaging
c. photoelectric effect
What effect does using a grid have on contrast?
a. Produce a longer scale of contrast
b. decrease contrast
c. increase contrast
d. have no effect on contrast
True/False For a given exposure technique, increasing part thickness decreases radiographic density.
If a person stands 12 ft from the source of exposure, receives an exposure of 16 R/min, and then moves 3 ft from the source of exposure, what would be the new exposure rate according to the inverse square law?
a. 256 R/min
b. 64 R/min
c. 1 R/min
d. 4 R/min
a; I1/I2 = (D2/D1)^2
If the first radiograph of a chest is done using 72" and 12 mAs and a second radiograph is done using 40 ", how much mAs should be used to maintain density?
a. 7 mAs
b. 2 mAs
c. 9 mAs
d 4 mAs
If a person stands 3 ft from the source of exposure, receives an exposure of 16 R/min and then moves to 6 ft from the source of exposure, what would the new exposure rate according to the inverse square law?
a. 4 R/min
b. 64 R/min
c. 256 R/min
d. 1 R/min
If the first radiograph of a foot is done using 4 mAs at 40" and a second radiograph is done using 50", how much mAs should be used to maintain density?
Considering the primary controller of radiographic density, which film has the greatest density?
a. 800 mA, .01 sec
b. 400 mA, 2 sec
c. 100 mA, .5 sec
d. 300 mA, 1 sec
In order to reduce patient exposure a _____ kVp and _____ mAs should be used when possible.
What is the minimum change in mAs that would result in a visible change in radiographic density?
When imaging the thoracic spine, in order to take advantage of the anode heel effect the most superior portion of the patient's spine should be placed beneath:
a. the cathode end of the tube
b. either end; it doesnt matter
c. middle of the tube
d. anode end of the tube
A quality radiograph is dones using 10 mAs, 70 kVp, and 12:1 ratio grid. How much mAs is needed to produce an image with the same density when the grid is removed?
none = 1
5:1 = 2
6:1 = 3
8:1 = 4
12:1 = 5
16:1 = 6
What would be appropriate change in mAs if kVp decrease by 15% and density needed to be maintained?
twice the mAs
Assuming all exposure factors remain unchanged what is result of changing to an IR with higher relative speed?
Assuming all produce appropriate density images, which of hte following would be best exposure technique choice when perform cxr on infant?
use 40 ms exposure time; shortest exposure time
Which of the following changes will result in increased density w/ no change in contrast?
A radiograph taken using 75 kVp @ 20 mAs. Which change in technique would increase contrast but maintain the same density?
a. 85 kVp @ 10 mAs
b. 85 kVp @ 40 mAs
c. 65 kVp @ 20 mAs
d. 65 kVp @ 40 mAs
d, decrease kVp = increase contrast
A radiograph taken using 65 kVp @ 10 mAs is too light. Which technique would double the optical density while produce a wider scale of contrast?
a. 75 @ 10
b. 75 @ 20
c. 55 @ 10
d. 55 @ 20
Which technique would give the highest patient dose?
a. 90 kVp/200 mA @ .02 sec
b. 87 kVp/400 mA @ .02 sec
c. 74 kVp/400 mA @ .04 sec
d. 65 kVp/300 mA @ .1 sec
Added filtration has the effect of ______ beam quality and ______ patient dose.
Which medical condition may require a lower technique?
d. pleural effusion
When only the optical density needs to be changed, only the ____ should be adjusted.
With aec the exposure is terminated when the optimum ______ is reached.
a. optical density
A radiograph with few densities but great differences among them is said to have:
a. high contrast
b. low contrast
c. long-scale contrast
d. medium-scale contrast
Abdomen image is done using 66 kVp and 40 mAs. Image desnity is appropriate but the image has too high (short scale) contrast. Which of these exposure factors would be the best change to make?
a. 56 @ 60
b. 66 @ 20
c. 76 @ 40
d. 76 @ 20
Image-forming xray include those which have been ____.
a. transmitted without interaction
b. scattered through compton scatter
c. absorbed through photoelectric interaction
d. b and a
Scattered radiation increases as _______ increases.
a. photoelectric absorption
b. field size
The xrays that are transmitted through the patient w/o interaction contribute to ______.
a. useful information
b. film fog
c. image noise
d. all above
The most commonly used beam restricting device is the ______
a. extension cone
b. variable collimator
c. aperture diaphragm
d. compression device
The use of ____ improves contrast and reduces patient dose.
b. high kVp
c. low kVp
d. less filtration
_____ is define as the ability to image two separate objects and visually detect one from the other.
The technologist primarily controls radiographic contrast by varying the ______.
a. image receptor
c. voltage ripple
Approximately ____% xray beam incident on patient is transmitted through patient w/o interaction to become part image from beam.
3 primary factor influencing intensity of scatter in image forming beam:
kVp, field size, patient thickness
Collimation acts to reduce scatter and its resultant image fog primarily by which of the following?
limiting area of exposure
Higher speed image receptors generally produce images with _______.
a. better resolution
b. increased noise
c. higher contrast
d. improved detail
The slope of the ____ portion of the characteristic curve shows the film contrast.
d. straight line
If 10% of view box light is transmitted through an area of film, what is the optical density in that area?
The densities above 2.5 on a film are represented in the ______ portion of the characteristic curve.
An artifact can be _______.
a. an object that is not part of the radiographed anatomy
b. patient motion
c. an improper grid or warped cassette
d. any of above
What is the purpose of the technique chart?
a. decrease patient exposure by always using the highest kVp
b. to ensure consistent image quality
c. to reduce repeats due to technique error and in turn reduce patient exposure
d. b and c
Which of the following is/are true regarding development of an effective technique chart?
a. processor must be consistent
b. equipment must be calibrated
c. equipment must be from same manufacturer
d. a and b
Which of the following is NOT required to be part of a standardized technique chart?
What is the appropriate change in kVp when using a variable kVp/fixed mAs for a 1 cm change in tissue thickness?
What kind of chart uses a kVp value that is high enough to adequately penetrate the part but doesnt diminish radiographic contrast?
When using the fixed kVp/variable mAs, if part thickness increases by 5 cm what needs to happen to the mAs?
True/False Technique chart will provide info as to how to recognize and compensate for additive pathology.
Departmental standard such as the SID or whether an exam is done table top or bucky should be determined.
prior to the development of technique chart