RAD 271 Unit 5

अब Quizwiz के साथ अपने होमवर्क और परीक्षाओं को एस करें!

With a given exposure, as intensifying-screen speed decreases, how is radiographic density affected? Select one: a. Decreases b. Increases c. Remains unchanged d. Is variable

a. Decreases

All of the following are related to recorded detail except Select one: a. mA. b. focal spot size. c. screen speed. d. OID.

a. mA.

SID affects recorded detail in which of the following ways? Select one: a. Recorded detail is directly related to SID. b. Recorded detail is inversely related to SID. c. As SID increases, recorded detail decreases. d. SID is not a detail factor.

a. Recorded detail is directly related to SID.

To produce a just perceptible increase in radiographic density, the radiographer must increase the Select one: a. mAs by 30%. b. mAs by 15%. c. kVp by 15%. d. kVp by 30%.

a. mAs by 30%.

A radiograph exposed using a 12:1 ratio grid may exhibit a loss of density at its lateral edges because the Select one: a. SID was too great. b. grid failed to move during the exposure. c. x-ray tube was angled in the direction of the lead strips. d. central ray was off-center.

a. SID was too great.

Which type of error results in grid cutoff at the periphery of the radiographic image? Select one: a. Off-focus b. Off-center c. Off-level d. Off-angle

a. Off-focus

Using fixed-mAs and variable-kVp technical factors, each centimeter increase in patient thickness requires what adjustment in kilovoltage? Select one: a. Increase 2 kVp b. Decrease 2 kVp c. Increase 4 kVp d. Decrease 4 kVp

a. Increase 2 kVp When the variable-kVp method is used, a particular mAs is assigned to each body part. As part thickness increases, the kVp (penetration) is also increased. The body part being radiographed must be carefully measured, and for each centimeter of increase in thickness, 2 kVp is added to the exposure. (Shephard, pp 299 300) #14992

Which of the following is most likely to produce a radiograph with a long scale of contrast? Select one: a. Increased photon energy b. Increased screen speed c. Increased mAs d. Increased SID

a. Increased photon energy

When a slow screen film system is used with a fast screen film automatic exposure control system, the resulting images Select one: a. are too light. b. are too dark. c. have improved detail. d. have poor detail.

a. are too light.

Which of the following is (are) causes of grid cutoff when using reciprocating grids? 1. Inadequate SID 2. X-ray tube off-center with the long axis of the lead strips 3. Angling the beam in the direction of the lead strips Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

a. 1 only

An exposure was made of a part using 300 mA and 0.06 second and using a 100-speed film-screen combination. An additional radiograph is requested using a 400-speed system to reduce motion unsharpness. Using 200 mA, all other factors remaining constant, what should be the new exposure time? Select one: a. 0.02 second b. 0.04 second c. 0.45 second d. 0.80 second

a. 0.02 second

Which of the following focal spot sizes should be employed for magnification radiography? Select one: a. 0.2 mm b. 0.6 mm c. 1.2 mm d. 2.0 mm

a. 0.2 mm

Which of the following quantities of filtration is most likely to be used in mammography? Select one: a. 0.5 mm Mo b. 1.5 mm Al c. 1.5 mm Cu d. 2.0 mm Cu

a. 0.5 mm Mo Soft tissue radiography requires the use of long-wavelength, low-energy x-ray photons. Very little filtration is used in mammography. Certainly, anything more than 1.0 mm of aluminum would remove the useful soft photons, and the desired high contrast could not be achieved. Dedicated mammographic units usually have molybdenum targets (for the production of soft radiation) and a small amount of molybdenum filtration. (Carlton & Adler, p 581) #15002

According to the line focus principle, an anode with a small angle provides 1. improved recorded detail. 2. improved heat capacity. 3. less heel effect. Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

a. 1 and 2 only

Methods that help reduce the production of scattered radiation include using 1. compression. 2. beam restriction. 3. a grid. Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

a. 1 and 2 only

What apparatus is needed for the construction of a sensitometric curve? 1. Penetrometer 2. Densitometer 3. Electrolytic canister Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

a. 1 and 2 only

Any images obtained using DXA bone densitometry 1. are used to evaluate accuracy of the ROI. 2. are used as evaluation for various bone/joint disorders. 3. reflect the similar attenuation properties of soft tissue and bone. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

a. 1 only

Exposure-type artifacts include 1. motion 2. static electricity marks 3. pi lines Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

a. 1 only

In which type of equipment does kVp decrease during the actual length of the exposure? 1. Condenser discharge mobile equipment 2. Battery operated mobile equipment 3. Fixed x-ray equipment Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

a. 1 only

Radiographic recorded detail is directly related to 1. SID. 2. OID. 3. imaging-system speed. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

a. 1 only

Recorded detail is directly related to 1. source-image distance (SID). 2. tube current. 3. focal spot size. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

a. 1 only

What are the effects of scattered radiation on the radiographic image? 1. It produces fog. 2. It increases contrast. 3. It increases grid cutoff. Select one: a. 1 only b. 2 only c. 1 and 2 only d. 1, 2, and 3

a. 1 only

An increase in kVp with appropriate compensation of mAs will result in 1. increased exposure latitude. 2. higher contrast. 3. increased density. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1 and 3 only

a. 1 only As the kilovoltage is increased, more penetration will occur and a greater range of densities (grays) will be apparent in the image. This is termed long scale or low contrast. In addition, as the kVp and scale of grays increase, the exposure latitude increases; the "margin for error" in technical factors becomes greater. As the mAs is decreased to compensate for the increased kVp, density should remain the same. (Shephard, p 204) #15975

In general, as the intensification factor increases, 1. radiographic density increases. 2. screen resolution increases. 3. recorded detail increases. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

a. 1 only Factors that contribute to an increase in the intensification factor generally function to reduce resolution. Slow-speed (detail or "extremity") screens resolve more line pairs per millimeter (lp/mm) than much faster screens. The use of fast screens results in some loss of recorded detail. As intensification factor increases, radiographic density generally increases. (Bushong, pp 222 223) #14918

X-ray photon energy is inversely related to 1. photon wavelength. 2. applied mA. 3. applied kVp. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

a. 1 only As kVp is increased, more high-energy photons are produced and the overall energy of the primary beam is increased. Photon energy is inversely related to wavelength; that is, as photon energy increases, wavelength decreases. An increase in milliamperage serves to increase the number of photons produced at the target, but is unrelated to their energy. (Selman, p 118) #14905

If 40 mAs and a 50-speed screen-film system were used for a particular exposure, what new mAs value would be required to produce the same density if the screen-film system were changed to 200 speed? Select one: a. 10 b. 20 c. 80 d. 160

a. 10

A satisfactory radiograph was made without a grid, using a 72-inch SID and 8 mAs. If the distance is changed to 40 inches and an 8:1 ratio grid is added, what should be the new mAs? Select one: a. 10 mAs b. 18 mAs c. 20 mAs d. 32 mas

a. 10 mAs

Which of the following groups of exposure factors will produce the greatest radiographic density? Select one: a. 100 mA, 0.30 second b. 200 mA, 0.10 second c. 400 mA, 0.03 second d. 600 mA, 0.03 second

a. 100 mA, 0.30 second

If 85 kVp, 400 mA, and 1/8 second was used for a particular exposure using single-phase equipment, which of the following milliamperage or time values would be required, all other factors being constant, to produce a similar density using 3-phase, 12-pulse equipment? Select one: a. 200 mA b. 600 mA c. 0.125 second d. 0.25 second

a. 200 mA

Which of the following groups of exposure factors would be most appropriate for an adult intravenous pyelogram (IVP)? Select one: a. 300 mA, 0.02 second, 72 kVp b. 300 mA, 0.01 second, 82 kVp c. 150 mA, 0.01 second, 94 kVp d. 100 mA, 0.03 second, 82 kVp

a. 300 mA, 0.02 second, 72 kVp Intravenous urography requires the use of iodinated contrast media. Low kilovoltage (about 70) is usually employed to enhance the photoelectric effect, and in turn to better visualize the renal collecting system. High kilovoltage will produce excessive scattered radiation and obviate the effect of the contrast agent. A higher milliamperage with a short exposure time is generally preferable. (Fauber, p 264)

If 32 mAs and 50-speed screens were used to produce a particular radiographic density, what new mAs value would be required to produce the same density if the screen speed was changed to 400? Select one: a. 4 b. 40 c. 175 d. 256

a. 4

The exposure factors of 300 mA, 0.017 second, and 72 kVp produce an mAs value of Select one: a. 5 b. 50 c. 500 d. 5000

a. 5

Of the following groups of exposure factors, which will produce the shortest scale of radiographic contrast? Select one: a. 500 mA, 0.040 second, 70 kVp b. 100 mA, 0.100 second, 80 kVp c. 200 mA, 0.025 second, 92 kVp d. 700 mA, 0.014 second, 80 kVp

a. 500 mA, 0.040 second, 70 kVp The single most important factor regulating radiographic contrast is kVp. The lower the kVp, the shorter the scale of contrast. All the mAs values in this problem have been adjusted for kVp changes to maintain density, but just a glance at each of the kilovoltages is often a good indicator of which will produce the longest scale or shortest scale contrast. (Shephard, pp 306, 308) #15022

Which of the following devices is used to overcome severe variation in patient anatomy or tissue density, providing more uniform radiographic density? Select one: a. Compensating filter b. Grid c. Collimator d. Intensifying screen

a. Compensating filter

How would the introduction of a 6-inch OID affect image contrast? Select one: a. Contrast would be increased. b. Contrast would be decreased. c. Contrast would not change. d. The scale of contrast would not change.

a. Contrast would be increased.

If a lateral projection of the chest is being performed on an asthenic patient and the outer photocells are selected, what is likely to be the outcome? Select one: a. Decreased density b. Increased density c. Scattered radiation fog d. Motion blur

a. Decreased density

If a radiograph exposed using a 12:1 ratio grid exhibits a loss of density at its lateral edges, it is probably because the Select one: a. SID was too great. b. grid failed to move during the exposure. c. x-ray tube was angled in the direction of the lead strips. d. central ray was off-center.

a. SID was too great.

Which of the following can be used to determine the sensitivity of a particular film emulsion? Select one: a. Sensitometric curve b. Dose-response curve c. Reciprocity law d. Inverse square law

a. Sensitometric curve

Screen film imaging is one example of a (n) Select one: a. analog system. b. digital system. c. electromagnetic system. d. direct-action radiation system.

a. analog system.

Crescent-shaped black marks on the finished radiograph are usually due to Select one: a. bending the film acutely. b. improper development. c. improper film storage. d. static electricity.

a. bending the film acutely.

Decreasing field size from 14 × 17 into 8 × 10 inches will Select one: a. decrease radiographic density and decrease the amount of scattered radiation generated within the part. b. decrease radiographic density and increase the amount of scattered radiation generated within the part. c. increase radiographic density and increase the amount of scattered radiation generated within the part. d. increase radiographic density and decrease the amount of scattered radiation generated within the part.

a. decrease radiographic density and decrease the amount of scattered radiation generated within the part.

The presence of dust or scratches on intensifying screens will cause Select one: a. decreased density in those areas of the image. b. increased density in those areas of the image. c. decreased density in all areas of the image. d. increased density in all areas of the image.

a. decreased density in those areas of the image.

If single-emulsion film was loaded into its cassette with the emulsion facing away from the intensifying screen, the resulting image would demonstrate Select one: a. decreased density. b. increased density. c. crossover. d. fog.

a. decreased density.

The conversion of the invisible latent image into a visible manifest image takes place in the Select one: a. developer. b. stop bath. c. first half of the fixer process. d. second half of the fixer process.

a. developer.

An overall image density arising from factors other than the light or radiation used to expose the image is called Select one: a. fog. b. log relative exposure. c. optical density. d. artifact.

a. fog.

Foreshortening of an anatomic structure means that Select one: a. it is projected on the IR smaller than its actual size. b. its image is more lengthened than its actual size. c. it is accompanied by geometric blur. d. it is significantly magnified.

a. it is projected on the IR smaller than its actual size.

If a 4-inch collimated field is changed to a 14-inch collimated field, with no other changes, the radiographic image will possess Select one: a. more density. b. less density. c. more detail. d. less detail.

a. more density.

Grid cutoff due to off-centering would result in Select one: a. overall loss of density. b. both sides of the image being underexposed. c. overexposure under the anode end. d. underexposure under the anode end.

a. overall loss of density.

The primary source of scattered radiation is the Select one: a. patient. b. tabletop. c. x-ray tube. d. grid.

a. patient.

An increase in kilovoltage will serve to Select one: a. produce a longer scale of contrast. b. produce a shorter scale of contrast. c. decrease the radiographic density. d. decrease the production of scattered radiation.

a. produce a longer scale of contrast.

The term spectral matching refers to the fact that film sensitivity must be matched with the Select one: a. proper color screen fluorescence. b. correct kVp level. c. correct mA level. d. proper developer concentration.

a. proper color screen fluorescence. Different types of intensifying screens are available for radiographic use, and they can differ greatly. Some intensifying screens emit a blue and others a green fluorescent light. Film emulsions are manufactured to be sensitive to one of these colors. This is termed spectral matching. If the film emulsion and intensifying screens are incorrectly matched, speed will be reduced. (Shephard, pp 65 66) #14967

The relationship between the height of a grid's lead strips and the distance between them is referred to as grid Select one: a. ratio. b. radius. c. frequency. d. focusing distance.

a. ratio.

A light-absorbing dye is frequently incorporated during the manufacture of screens to Select one: a. reduce the diffusion of fluorescent light. b. increase image contrast. c. increase screen speed. d. increase the useful life of the screen.

a. reduce the diffusion of fluorescent light.

The device used to give a film a predetermined exposure in order to test its response to processing is called the Select one: a. sensitometer. b. densitometer. c. step wedge. d. spinning top.

a. sensitometer.

Misalignment of the tube-part-IR relationship results in Select one: a. shape distortion. b. size distortion. c. magnification. d. blur.

a. shape distortion. Shape distortion (foreshortening, elongation) is caused by improper alignment of the tube, part, and IR. Size distortion, or magnification, is caused by too great an OID or too short a SID. Focal spot blur is caused by the use of a large focal spot. (Fauber, p 93)

The line focus principle expresses the relationship between Select one: a. the actual and the effective focal spot. b. exposure given the IR and resultant density. c. SID used and resultant density. d. grid ratio and lines per inch.

a. the actual and the effective focal spot.

Foreshortening can be caused by Select one: a. the radiographic object being placed at an angle to the IR. b. excessive distance between the object and the IR. c. insufficient distance between the focus and the IR. d. excessive distance between the focus and the IR.

a. the radiographic object being placed at an angle to the IR.

When an automatic processor is started up at the beginning of the day, or restarted after an extended standby period, the technologist should process an Select one: a. unexposed, undeveloped 14 × 17 inches film. b. exposed and developed 14 × 17 inches film. c. unexposed and developed 14 × 17 inches film. d. unexposed or unexposed and developed 14 × 17 inches film.

a. unexposed, undeveloped 14 × 17 inches film.

An exposure was made at 40-inch SID, using 5 mAs and 105 kVp with an 8:1 grid. In an effort to improve radiographic contrast, the image is repeated using a 12:1 grid and 90 kVp. Which of the following exposure times will be most appropriate, using 400 mA, to maintain the original density? Select one: a. 0.01 second b. 0.03 second c. 0.1 second d. 0.3 second

b. 0.03 second The use of high kVp with a fairly low-ratio grid will be ineffective in ridding the remnant beam of scattered radiation. To improve contrast in this example, it has been decided to decrease the kilovoltage by 15%, thus making it necessary to increase the mAs from 5 to 10 mAs. Because an increase in the grid ratio to 12:1 is also desired, another change in mAs will be required (remember, 10 mAs is now the old mAs): Then complete the formuala below to determine the exposure time required with 400 mA to produce 12.5 mAs: 400x = 12.5 x = 0.03 second exposure (Selman, p 214) #15980

A satisfactory radiograph of the abdomen was made at a 42-inch SID using 300 mA, 0.06-second exposure, and 80 kVp. If the distance is changed to 38 inches, what new exposure time would be required? Select one: a. 0.02 second b. 0.05 second c. 0.12 second d. 0.15 second

b. 0.05 second

If 300 mA has been selected for a particular exposure, what exposure time should be selected to produce 18 mAs? Select one: a. 0.04 b. 0.06 c. 0.4 d. 0.6

b. 0.06

An exposure was made at a 38-inch SID using 300 mA, a 0.03-second exposure, and 80 kVp with a 400 film-screen combination and an 8:1 grid. It is desired to repeat the radiograph and, in order to improve recorded detail, to use a 42-inch SID and a 200-speed film-screen combination. With all other factors remaining constant, what exposure time will be required to maintain the original radiographic density? Select one: a. 0.03 second b. 0.07 second c. 0.14 second d. 0.36 second

b. 0.07 second

An unexposed and processed film will have a density of about Select one: a. zero. b. 0.1. c. 1.0. d. 2.5.

b. 0.1. Film that is unexposed and has been processed will not be completely clear. The blue-tinted base contributes a small measure of density. A small but measurable amount of exposure from background radiation can also be present, and processing itself produces a small amount of density from chemical fog. Together, this is expressed as base-plus fog and should never exceed a density of 0.2. (Fauber, p 198) #14974

What pixel size has a 1024 × 1024 matrix with a 35-cm FOV? Select one: a. 30 mm b. 0.35 mm c. 0.15 mm d. 0.03 mm

b. 0.35 mm

A film emerging from the automatic processor exhibits excessive density. This may be attributable to which of the following? 1. Developer temperature too high 2. Chemical fog 3. Underreplenishment Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

An increase in kVp will have which of the following effects? 1. More scattered radiation will be produced. 2. The exposure rate will increase. 3. Radiographic contrast will increase. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Bone densitometry is often performed to 1. measure degree of bone (de)mineralization. 2. evaluate results of osteoporosis treatment/therapy. 3. evaluate condition of soft tissue adjacent to bone. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Cassette front material can be made of which of the following? 1. Carbon fiber 2. Magnesium 3. Lead Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Exposure rate increases with an increase in 1. mA. 2. kVp. 3. SID. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

For which of the following examinations can the anode heel effect be an important consideration? 1. Lateral thoracic spine 2. AP femur 3. RAO sternum Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Hardener is added to the developer solution of automatic processors to 1. keep emulsion swelling to a minimum. 2. decrease the possibility of a processor jam-up. 3. remove unexposed silver halide crystals. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

How can the radiographer reduce the amount of scattered radiation generated during a radiographic examination? 1. Use optimum kVp. 2. Collimate closely. 3. Use a grid. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

b. 1 and 2 only

If the developer temperature in the automatic processor is higher than normal, what will be the effect on the finished radiograph? 1. Loss of contrast 2. Increased density 3. Wet, tacky films Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

In radiography of a large abdomen, which of the following is (are) effective way(s) to minimize the amount of scattered radiation reaching the IR? 1. Use of close collimation 2. Use of compression devices 3. Use of a low-ratio grid Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Radiographic contrast is a result of 1. differential tissue absorption. 2. emulsion characteristics. 3. proper regulation of mAs. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

b. 1 and 2 only

The term latitude describes 1. an emulsion's ability to record a range of densities. 2. the degree of error tolerated with given exposure factors. 3. the conversion efficiency of a given intensifying screen. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Which of the following can impact the visibility of the anode heel effect? 1. SID 2. Image recorder size 3. Screen speed Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Which of the following factors affect(s) both radiographic density and intensifying screen speed? 1. Thickness of phosphor layer 2. Type of phosphors used 3. Thickness of spongy screen support Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Which of the following may be used to control the production of scattered radiation? 1. Restricted field size 2. Use of optimal kVp 3. Use of grids Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Which of the following methods can be effectively used to decrease differential absorption, providing a longer scale of contrast in the diagnostic range? 1. Using high kVp and low mAs factors 2. Using compensating filtration 3. Using factors that increase the photoelectric effect Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Which of the following will have an effect on radiographic contrast? 1. Beam restriction 2. Grids 3. Focal spot size Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only

Bone densitometry is often performed to 1. measure degree of bone (de) mineralization. 2. evaluate results of osteoporosis treatment/therapy. 3. evaluate condition of soft tissue adjacent to bone. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only DXA imaging is used to evaluate bone mineral density (BMD). Bone densitometry, DXA, can be used to evaluate bone mineral content of the body, or part of it, to diagnose osteoporosis or to evaluate the effectiveness of treatments for osteoporosis. It is the most widely used method of bone densitometry it is low dose, preceise, and uncomplicated to use/perform. DXA uses two photon energies one for soft tissue and one for bone. Since bone is more dense and attenuates x-ray photons more readily, their attenuation is calculated to represent the degree of bone density. Soft tissue attenuation information is not used to measure bone density. (Ballinger & Frank, vol 3, pp 488 489)

The amount of replenisher solution added as a film enters the automatic processor is related to the 1. size of the film. 2. temperature of the solution. 3. number of films processed. Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 3 only

The speed of an intensifying screen is influenced by which of the following factors? 1. Phosphor layer thickness 2. Antihalation backing 3. Phosphor type used Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 3 only

The effect that differential absorption has on radiographic contrast of a high subject contrast part can be minimized by 1. using a compensating filter. 2. using high-kVp exposure factors. 3. increased collimation. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only Differential absorption refers to the different attenuation, or absorption, properties of adjacent body tissues. Two parts with widely differing absorption characteristics will produce a high radiographic contrast. Frequently, exposure factors that would properly expose one part will severely overexpose or underexpose the neighboring part (as with lungs vs thoracic spine). This effect can be minimized by the use of a compensating filter or by the use of high kilovoltage (for more uniform penetration). Increased collimation is important in the control of patient dose and scattered radiation, not differential absorption. (Bushong, pp 169, 170)

Which of the following conditions would require an increase in exposure factors? 1. Congestive heart failure 2. Pleural effusion 3. Emphysema Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

b. 1 and 2 only Emphysema is abnormal distention of the alveoli (or tissue spaces) with air. The presence of abnormal amounts of air makes it necessary to decrease from normal exposure factors. Congestive heart failure and pleural effusion involve abnormal amounts of fluid in the chest and thus require an increase in exposure factors. (Carlton & Adler, p 258) #15027

Characteristics of low ratio focused grids include the following: 1. they have a greater focal range 2. they are less efficient in collecting SR 3. they can be used inverted Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only Grid ratio compares the height of the lead strip to the distance between the lead strips. Focused grids have their lead strips angled so as to parallel the divergent x-ray beam. The higher the grid ratio, the greater the grid's efficiency in absorbing scattered radiation before it reaches the image receptor but the more critical the centering and distance specifications. Although higher ratio focused grids absorb more SR they have a narrower focal range (focusing distance) and grid/tube centering becomes much more critical. Focused grids must not be accidentally inverted to do so would cause the lead strips to be placed exactly in the path of the lead strips (grid cutoff), everywhere but in the center of the grid. (Ballinger & Frank, vol 3, p 235)

Types of moving grid mechanisms include 1. oscillating. 2. reciprocating. 3. synchronous. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 2 and 3 only

b. 1 and 2 only Grids are devices constructed of alternating strips of lead foil and radiolucent interspacing material. They are placed between the patient and the IR, and they function to remove scattered radiation from the remnant beam before it forms the latent image. Stationary grids will efficiently remove scattered radiation from the remnant beam; however, their lead strips will be imaged on the radiograph. If the grid is made to move (usually in a direction perpendicular to the lead strips) during the exposure, the lead strips will be effectively blurred. The motion of a moving grid, or Potter-Bucky diaphragm, may be reciprocating (equal strokes back and forth), oscillating (almost circular direction), or catapult (rapid forward motion and slow return). Synchronous refers to a type of x-ray timer. (Bushong, p 256) #14945

Which of the following conditions require(s) a decrease in technical factors? 1. Emphysema 2. Osteomalacia 3. Atelectasis Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only Subcutaneous emphysema is a pathologic distention of tissues with air; pulmonary emphysema is a chronic disease characterized by overdistention of the alveoli with air. Osteomalacia is a softening of bone so that it becomes flexible, brittle, and deformed. Both of these conditions involve a decrease in tissue density, and therefore require a decrease in exposure factors. Atelectasis is a collapsed or airless lung; it requires an increase in exposure factors. (Carlton & Adler, p 257) #15978

Which of the following would be useful for an examination of a patient suffering from Parkinson's disease? 1. High-speed screens 2. Short exposure time 3. Compensating filtration Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

b. 1 and 2 only The shortest possible exposure should be used as a matter of routine. Parkinson's disease is characterized by uncontrollable tremors, and the resulting unsharpness can destroy image detail. It is therefore necessary to use as fast an imaging system as possible. High-speed (rare earth) intensifying screens will permit a considerable reduction in mAs (specifically, exposure time). Compensating filtration is unrelated to the problem and is not indicated here. (Fauber, p 188)

Which of the following can result from improper film storage or darkroom conditions? 1. Safelight fog 2. Background radiation fog 3. Screen lag Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only If the safelight bulb is of a higher wattage than it should be, the safelight filter is incorrect for the film type, or the filter is cracked, film fog can occur. If film is not stored in a radiation-safe area, it can be fogged by background radiation. Screen lag is not caused by improper film storage conditions, but rather by aged or defective intensifying screens. (Selman, pp 190 191) #14996

Which of the following is (are) classified as rare earth phosphors? 1. Lanthanum oxybromide 2. Gadolinium oxysulfide 3. Cesium iodide Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 2 only Rare earth phosphors have a greater conversion efficiency than do other phosphors. Lanthanum oxybromide is a blue-emitting rare earth phosphor, and gadolinium oxysulfide is a green-emitting rare earth phosphor. Cesium iodide is the phosphor used on the input screen of image intensifiers; it is not a rare earth phosphor. (Shephard, p 68) #15010

Which of the following have an effect on recorded detail? 1. Focal spot size 2. Type of rectification 3. SID Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 3 only

The function(s) of the fixer in film processing is (are) to 1. remove the unexposed silver bromide crystals. 2. change the unexposed silver bromide crystals to black metallic silver. 3. harden the emulsion. Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 3 only Developing agents change the exposed silver bromide crystals to black metallic silver, thus producing a manifest image. The fixer solution removes the unexposed silver bromide crystals from the emulsion and hardens the gelatin emulsion, thus ensuring permanence of the radiograph. (Fauber, p 167) #14943

Which of the following is (are) characteristics of a 16:1 grid? 1. It absorbs more primary radiation than an 8:1 grid. 2. It has more centering latitude than an 8:1 grid. 3. It is used with higher kVp exposures than an 8:1 grid. Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

b. 1 and 3 only High-kilovoltage exposures produce large amounts of scattered radiation, and high-ratio grids are often used with high-kV techniques in an effort to absorb more of this scattered radiation. However, as more scattered radiation is absorbed, more primary radiation is absorbed as well. This accounts for the increase in mAs required when changing from an 8:1 to a 16:1 grid. In addition, precise centering and positioning become more critical; a small degree of inaccuracy is more likely to cause grid cutoff in a high-ratio grid. (Bushong, pp 252 255) #15979

Of the following groups of technical factors, which will produce the greatest radiographic density? Select one: a. 10 mAs, 74 kVp, 44-inch SID b. 10 mAs, 74 kVp, 36-inch SID c. 5 mAs, 85 kVp, 48-inch SID d. 5 mAs, 85 kVp, 40-inch SID

b. 10 mAs, 74 kVp, 36-inch SID If A and B are reduced to 5 mAs for mAs consistency, the kVp will increase to 85 kVp in both cases, thereby balancing radiographic densities. Thus, the greatest density is determined by the shortest SID (greatest exposure rate). (Shephard, pp 306 307)

In a PA projection of the chest being used for cardiac evaluation, the heart measures 15.2 cm between its widest points. If the magnification factor is known to be 1.3, what is the actual diameter of the heart? Select one: a. 9.7 cm b. 11.7 cm c. 19.7 cm d. 20.3 cm

b. 11.7 cm

An increase in the kilovoltage applied to the x-ray tube increases the 1. x-ray wavelength. 2. exposure rate. 3. patient absorption. Select one: a. 1 only b. 2 only c. 2 and 3 only d. 1, 2, and 3

b. 2 only

The use of which of the following is (are) essential in magnification radiography? 1. High-ratio grid 2. Fractional focal spot 3. Direct exposure film Select one: a. 1 only b. 2 only c. 1 and 3 only d. 1, 2, and 3

b. 2 only Magnification radiography is used to enlarge details to make them more perceptible. Hairline fractures, minute blood vessels, and microcalcifications are candidates for magnification radiography. The problem of magnification unsharpness is overcome by using a fractional focal spot; larger focal spot sizes will produce excessive blurring unsharpness. Grids are usually unnecessary in magnification radiography because of the air-gap effect produced by the OID. A direct-exposure technique would not be likely to be used because of the excessive exposure required. (Selman, pp 226 228)

A lateral radiograph of the lumbar spine was made using 200 mA, 1-second exposure, and 90 kVp. If the exposure factors were changed to 200 mA, 1/2 second, and 104 kVp, there would be an obvious change in which of the following? 1. Radiographic density 2. Scale of radiographic contrast 3. Distortion Select one: a. 1 only b. 2 only c. 2 and 3 only d. 1, 2, and 3

b. 2 only The original mAs (regulating radiographic density) was 200. The original kVp (regulating radiographic contrast) was 90. The mAs was cut in half, to 100, causing a decrease in density. The kVp was increased (by 15%) to compensate for the density loss and thereby increase the scale of contrast. (Shephard, p 203)

A 3-inch object to be radiographed at a 36-inch SID lies 4 inches from the image recorder. What will be the image width? Select one: a. 2.6 inches b. 3.3 inches c. 26 inches d. 33 inches

b. 3.3 inches

Which of the following groups of technical factors will produce the greatest radiographic density? Select one: a. 400 mA, 0.010 second, 94 kVp, 100-speed screens b. 500 mA, 0.008 second, 94 kVp, 200-speed screens c. 200 mA, 0.040 second, 94 kVp, 50-speed screens d. 100 mA, 0.020 second, 80 kVp, 200-speed screens

b. 500 mA, 0.008 second, 94 kVp, 200-speed screens

Which of the following groups of exposure factors will produce the longest scale of contrast? Select one: a. 200 mA, 0.25 second, 70 kVp, 12:1 grid b. 500 mA, 0.10 second, 90 kVp, 8:1 grid c. 400 mA, 0.125 second, 80 kVp, 12:1 grid d. 300 mA, 0.16 second, 70 kVp, 8:1 grid

b. 500 mA, 0.10 second, 90 kVp, 8:1 grid Of the given factors, kilovoltage and grid ratio will have a significant effect on the scale of radiographic contrast. The mAs values are almost identical. Because an increased kilovoltage and low-ratio grid combination would allow the greatest amount of scattered radiation to reach the IR, thereby producing more gray tones, B is the best answer. Group D also uses a low-ratio grid, but the kilovoltage is too low to produce as many gray tones as Group B. #15974

An exposure was made using 12 mAs and 60 kVp. If the kVp was changed to 70 to obtain longer-scale contrast, what should be the new mAs? Select one: a. 3 b. 6 c. 18 d. 24

b. 6

If 0.05 second was selected for a particular exposure, what mA would be necessary to produce 30 mAs? Select one: a. 900 b. 600 c. 500 d. 300

b. 600

Which combination of exposure factors will most likely contribute to producing the longest-scale contrast? mAs kVp Film-Screen Grid Field Size (A) 10 70 400 5:1 14 × 17 inches (B) 12 90 200 8:1 14 × 17 inches (C) 15 90 200 12:1 8 × 10 inches (D) 20 80 400 10:1 11 × 14 inches Select one: a. A only b. A and B only c. B and C only d. A, B, and C

b. A and B only

If the radiographer is unable to achieve a short OID because of the structure of the body part or patient condition, which of the following adjustments can be made to minimize magnification distortion? Select one: a. A smaller focal spot size should be used. b. A longer SID should be used. c. Faster intensifying screens should be used. d. A lower-ratio grid should be used.

b. A longer SID should be used.

Which of the following terms refers to light being reflected from one intensifying screen, through the film, to the opposite emulsion and screen? Select one: a. Reflectance b. Crossover c. Scatter d. Filtration

b. Crossover

What will result from using single-emulsion film in an image receptor having two intensifying screens? Select one: a. Double exposure b. Decreased density c. Increased recorded detail d. Greater latitude

b. Decreased density

Which of the following is most likely to occur as a result of using a 30-inch SID with a 14 × 17-inch IR to radiograph a fairly homogeneous structure? Select one: a. Production of quantum mottle b. Density variation between opposite ends of the IR c. Production of scatter radiation fog d. Excessively short-scale contrast

b. Density variation between opposite ends of the IR

When green-sensitive rare earth screens are properly matched with the correct film, what type of safelight should be used in the darkroom? Select one: a. Wratten 6B b. GBX c. Amber d. None

b. GBX It is essential that the darkroom safelight filter color is correctly matched with the type/sensitivity of film emulsion being used. The GBX is a red filter that is safe with green-sensitive film emulsion. The amber-colored Wratten 6B filter is safe for blue-sensitive film only. Although using no safelight is possible, it is not a practical way to function. (Selman, p 191) #15941

Which of the following will result if developer replenishment is inadequate? Select one: a. Images with excessively high contrast b. Images with excessively low contrast c. Images with excessively high density d. Dry, brittle films

b. Images with excessively low contrast As films are developed, the developer solution becomes weaker and oxidation products are produced in the solution. If sufficient replenishment of new developer solution does not take place, the activity of the older solution decreases, and chemical fog is produced. Films lack contrast and have a flat, gray appearance. (Shephard, p 153) #14998

What combination of exposure factors and image receptor speed would best function to reduce quantum mottle? Select one: a. Decreased mAs, decreased kVp, fast-speed screens b. Increased mAs, decreased kVp, slow-speed screens c. Decreased mAs, increased kVp, fast-speed screens d. Increased mAs, increased kVp, fast-speed screens

b. Increased mAs, decreased kVp, slow-speed screens

For which of the following examinations may the use of a grid not be necessary in the adult patient? Select one: a. Hip b. Knee c. Abdomen d. Lumbar spine

b. Knee

Which of the following pathologic conditions will probably require a decrease in exposure factors? Select one: a. Osteomyelitis b. Osteoporosis c. Osteosclerosis d. Osteochondritis

b. Osteoporosis

Which reducing agent is responsible for producing the gray tones on the radiographic image? Select one: a. Hydroquinone b. Phenidone c. Sodium sulfite d. Ammonium thiosulfate

b. Phenidone

The relationship between the intensity of light striking a film and the intensity of light transmitted through the film is an expression of which of the following? Select one: a. Radiographic contrast b. Radiographic density c. Recorded detail d. Radiographic filtration

b. Radiographic density The greater the quantity of black metallic silver deposited on a film, the greater the radiographic density. The greater the degree of radiographic density (degree of blackening), the less the quantity of illuminator light transmitted through the film. Therefore, the relationship between the amount of illuminator light striking the film and the amount of light transmitted through the film is an expression of radiographic density. It is expressed by the formula #14931

Which portion of the characteristic curve would most likely represent a density of 1.0? Select one: a. Toe b. Straight-line portion c. Shoulder d. Dmax

b. Straight-line portion

Image receptors/cassettes frequently have a lead foil layer behind the rear screen that functions to Select one: a. improve penetration. b. absorb backscatter. c. preserve resolution. d. increase the screen speed.

b. absorb backscatter.

X-ray film emulsion is most sensitive to safelight fog Select one: a. before exposure and development. b. after exposure. c. during development. d. at low humidity.

b. after exposure.

The purpose of the automatic processor's circulation system is to Select one: a. monitor and adjust temperature. b. agitate, mix, and filter solutions. c. move the film and change its direction. d. monitor the solution and replace it as necessary.

b. agitate, mix, and filter solutions.

The radiographic accessory used to measure the thickness of body parts in order to determine optimum selection of exposure factors is the: Select one: a. fulcrum b. caliper c. densitometer d. ruler

b. caliper

A wire mesh test is performed to diagnose screen Select one: a. lag. b. contact. c. resolution. d. intensification.

b. contact.

The process of "leveling and windowing" of digital images determines the image Select one: a. spatial resolution. b. contrast. c. pixel size. d. matrix size.

b. contrast.

The device that is used for the direct measurement of optical density is the Select one: a. sensitometer. b. densitometer. c. penetrometer. d. H&D curve.

b. densitometer.

A compensating filter is used to Select one: a. absorb the harmful photons that contribute only to patient dose. b. even out widely differing tissue densities. c. eliminate much of the scattered radiation. d. improve fluoroscopy.

b. even out widely differing tissue densities.

Boxes of film stored in too warm an area may be subject to Select one: a. static marks. b. film fog. c. high contrast. d. loss of density.

b. film fog.

Unopened boxes of radiographic film should be stored away from radiation and Select one: a. in the horizontal position. b. in the vertical position. c. stacked with the oldest on top. d. stacked with the newest on top.

b. in the vertical position.

Most laser film must be handled Select one: a. under a Wratten 6B safelight. b. in total darkness. c. under a GBX safelight. d. with high-temperature processors.

b. in total darkness.

Using a short (25 30 inches) SID with a large size (14 × 17 inches) image receptor is likely to Select one: a. increase the scale of contrast. b. increase the anode heel effect. c. cause malfunction of the AEC. d. cause premature termination of the exposure.

b. increase the anode heel effect. Use of a short SID with a large-size image receptor (and also with anode angles of 10° or less) causes the anode heel effect to be much more apparent. The x-ray beam needs to diverge more to cover a large-size image receptor, and it needs to diverge even more for coverage as the SID decreases. The x-ray beam has no problem diverging toward the cathode end of the beam, but as it tries to diverge toward the anode end of the beam, it is eventually stopped by the anode (x-ray photons are absorbed by the anode). This causes a decrease in beam intensity at the anode end of the beam and is characteristic of the anode heel effect. (Carlton & Adler, p 120) #14910

When involuntary motion must be considered, the exposure time may be cut in half if the kVp is Select one: a. doubled. b. increased by 15%. c. increased by 25%. d. increased by 35%.

b. increased by 15%.

Improper spectral matching between rare earth intensifying screens and film emulsion results in Select one: a. longer-scale contrast. b. insufficient density. c. decreased recorded detail. d. excessive density.

b. insufficient density.

All other factors remaining the same, if a 14 × 17-inch field is collimated to a 4-inch square field, the radiographic image will demonstrate Select one: a. more density. b. less density. c. more detail. d. less detail.

b. less density.

Which of the following is the factor of choice for the regulation of radiographic (optical) density? Select one: a. kVp b. mAs c. SID d. Filtration

b. mAs

How are mAs and radiographic density related in the process of image formation? Select one: a. mAs and radiographic density are inversely proportional. b. mAs and radiographic density are directly proportional. c. mAs and radiographic density are related to image unsharpness. d. mAs and radiographic density are unrelated.

b. mAs and radiographic density are directly proportional.

A focal spot size of 0.3 mm or smaller is essential for Select one: a. small-bone radiography. b. magnification radiography. c. tomography. d. fluoroscopy.

b. magnification radiography.

The continued emission of light by a phosphor after the activating source has ceased is termed Select one: a. fluorescence. b. phosphorescence. c. image intensification. d. quantum mottle.

b. phosphorescence. Fluorescence occurs when an intensifying screen absorbs x-ray photon energy, emits light, and then ceases to emit light as soon as the energizing source ceases. Phosphorescence occurs when an intensifying screen absorbs x-ray photon energy, emits light, and continues to emit light for a short time after the energizing source ceases. Quantum mottle is the freckle-like appearance on some radiographs made using a very fast imaging system. The brightness of a fluoroscopic image is amplified through image intensification. (Bushong, p 221) #14960

Exposed silver halide crystals are changed to black metallic silver by the Select one: a. preservative. b. reducers. c. activators. d. hardener.

b. reducers.

Very low humidity in the darkroom can lead to Select one: a. crinkle marks. b. static electrical discharge. c. excessive emulsion swelling. d. chemical fog.

b. static electrical discharge.

The variation in photon distribution between the anode and cathode ends of the x-ray tube is known as Select one: a. the line focus principle. b. the anode heel effect. c. the inverse square law. d. Bohr's theory.

b. the anode heel effect.

As grid ratio is increased, Select one: a. the scale of contrast becomes longer. b. the scale of contrast becomes shorter. c. radiographic density increases. d. radiographic distortion decreases.

b. the scale of contrast becomes shorter.

Focal spot blur is greatest Select one: a. directly along the course of the central ray. b. toward the cathode end of the x-ray beam. c. toward the anode end of the x-ray beam. d. as the SID is increased.

b. toward the cathode end of the x-ray beam.

Referring to the given information, and with all other factors remaining constant, which of the following exposure times would be required to maintain radiographic density at a 36-inch SID using the 500-mA station, and with an increase to 87 kVp? 400 mA; 0.05 sec; 76 kVp; 40" SID Select one: a. 0.04 second b. 0.08 second c. 0.016 second d. 0.032 second

c. 0.016 second

A radiograph made using 300 mA, 0.1 second, and 75 kVp exhibits motion unsharpness, but otherwise satisfactory technical quality. The radiograph will be repeated using a shorter exposure time. Using 86 kV and 500 mA, what should be the new exposure time? Select one: a. 0.12 second b. 0.06 second c. 0.03 second d. 0.01 second

c. 0.03 second

The exposure factors of 300 mA, 0.07 second, and 95 kVp were used to produce a particular radiographic density and contrast. A similar radiograph can be produced using 500 mA, 80 kVp, and Select one: a. 0.01 second. b. 0.04 second. c. 0.08 second. d. 0.16 second.

c. 0.08 second.

Referring to the original factors given, and with all other factors remaining constant, which of the following exposure times would be required to maintain radiographic density using 400 mA and a 200 speed film-screen system, and with the addition of an 8:1 grid? 200 mA, 0.1 second, 80 kVp, 400 speed film-screen system, no grid Select one: a. 0.12 second b. 0.18 second c. 0.4 second d. 0.6 second

c. 0.4 second

A grid is usually employed 1. when radiographing a large or dense body part. 2. when using high kilovoltage. 3. when less patient dose is required. Select one: a. 1 only b. 3 only c. 1 and 2 only d. 1, 2, and 3

c. 1 and 2 only

A grid is usually employed in which of the following circumstances? 1. When radiographing a large or dense body part 2. When using high kilovoltage 3. When a lower patient dose is required Select one: a. 1 only b. 3 only c. 1 and 2 only d. 1, 2, and 3

c. 1 and 2 only

The squeegee assembly in an automatic processor 1. functions to remove excess solution from films. 2. is located near the crossover rollers. 3. helps establish the film's rate of travel. Select one: a. 1 only b. 2 only c. 1 and 2 only d. 1, 2, and 3

c. 1 and 2 only

Which of the following affect(s) both the quantity and the quality of the primary beam? 1. Half-value layer (HVL) 2. kVp 3. mA Select one: a. 1 only b. 2 only c. 1 and 2 only d. 1, 2, and 3

c. 1 and 2 only

With all other factors constant, as digital image matrix size increases, 1. pixel size decreases. 2. resolution increases. 3. pixel size increases. Select one: a. 1 only b. 2 only c. 1 and 2 only d. 2 and 3 only

c. 1 and 2 only

Grid interspace material can be made of 1. plastic. 2. lead. 3. aluminum. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

c. 1 and 3 only

If a radiograph exhibits insufficient density, this might be attributed to 1. inadequate kVp. 2. inadequate SID. 3. grid cutoff. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

c. 1 and 3 only

Terms that refer to shape distortion include 1. foreshortening. 2. attenuation. 3. elongation. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

c. 1 and 3 only

Which of the following function(s) to reduce the amount of scattered radiation reaching the IR? 1. Grid devices 2. Restricted focal spot size 3. Beam restrictors Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

c. 1 and 3 only

Which of the following will contribute to the production of longer-scale radiographic contrast? 1. An increase in kV 2. An increase in grid ratio 3. An increase in photon energy Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

c. 1 and 3 only

All of the following statements regarding dual x-ray absorptiometry are true: 1. two x-ray photon energies are used. 2. radiation dose is considerable. 3. photon attenuation by bone is calculated. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

c. 1 and 3 only Dual x-ray absorptiometry (DXA) imaging is used to evaluate bone mineral density (BMD). It is the most widely used method of bone densitometry it is low dose, precise, and uncomplicated to use/perform. DXA uses two photon energies one for soft tissue and one for bone. Since bone is more dense and attenuates x-ray photons more readily, their attenuation is calculated to represent the degree of bone density. Bone densitometry, DXA, can be used to evaluate bone mineral content of the body, or part of it, to diagnose osteoporosis or to evaluate the effectiveness of treatments for osteoporosis. (Ballinger & Frank, vol 3, pp 488 489)

Resolution in computed radiography increases as 1. laser beam size decreases 2. monitor matrix size decreases 3. PSP crystal size decreases Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

c. 1 and 3 only Spatial resolution in CR is impacted by the size of the PSP, the size of the scanning laser beam, and monitor matrix size. High-resolution monitors (2 4 K) are required for high-quality, high-resolution image display. Thelargerthematrixsize, thebettertheimageresolution. Typical image matrix size (rows and columns) used in chest radiography is 2048 × 2048. As in traditional radiography, spatial resolution is measured in line pairs per mm. As matrix size is increased, there are more and smaller pixels in the matrix therefore improved spatial resolution. Other factors contributing to image resolution are the size of the laser beam and the size of the PSP/IP phosphors. Smaller phosphor size improves resolution in ways similar to that of intensifying screens anything that causes an increase in light diffusion will result in a decreae in resolution. Smaller phosphors in the PSP plate allow less light diffusion. Additionally, the scanning laser light must be the correct intensity and size. A narrow laser beam is required for optimum resolution. (Shephard, p 336)

An exposure was made using 300 mA, 0.04-second exposure, and 85 kVp. Each of the following changes will decrease the radiographic density by one-half except a change to Select one: a. 1/50-second exposure. b. 72 kVp. c. 10 mAs. d. 150 mA.

c. 10 mAs.

Of the following groups of exposure factors, which will produce the greatest radiographic density? Select one: a. 200 mA, 0.03 second, 72-inch source-image distance (SID) b. 100 mA, 0.03 second, 36-inch SID c. 100 mA, 0.06 second, 36-inch SID d. 200 mA, 0.06 second, 72-inch SID

c. 100 mA, 0.06 second, 36-inch SID

A satisfactory radiograph was made using a 40-inch SID, 10 mAs, and a 12:1 grid. If the examination will be repeated at a distance of 48 inches and using an 8:1 grid, what should be the new mAs to maintain the original density? Select one: a. 5.6 b. 8.8 c. 11.5 d. 14.4

c. 11.5

Exposure factors of 110 kVp and 12 mAs are used with an 8:1 grid for a particular exposure. What should be the new mAs if a 12:1 grid is substituted? Select one: a. 3 b. 9 c. 15 d. 18

c. 15

Exposure factors of 90 kVp and 4 mAs are used for a particular nongrid exposure. What should be the new mAs if an 8:1 grid is added? Select one: a. 8 b. 12 c. 16 d. 20

c. 16

An exposure was made using 600 mA, 0.04-second exposure, and 85 kVp. Each of the following changes will serve to decrease the radiographic density by one half except change to Select one: a. 1/50-second exposure. b. 72 kVp. c. 18 mAs. d. 300 mA.

c. 18 mAs.

In digital imaging, as the size of the image matrix increases: 1. FOV increases 2. pixel size decreases 3. spatial resolution increases Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

c. 2 and 3 only

Recorded detail can be improved by decreasing 1. the SID. 2. the OID. 3. motion unsharpness. Select one: a. 1 only b. 3 only c. 2 and 3 only d. 1, 2, and 3

c. 2 and 3 only

Types of shape distortion include 1. magnification. 2. elongation. 3. foreshortening. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

c. 2 and 3 only

Which of the following are methods used for silver reclamation? 1. Photoelectric method 2. Metallic replacement method 3. Electrolytic method Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

c. 2 and 3 only

Which of the following materials may be used as grid interspace material? 1. Lead 2. Plastic 3. Aluminum Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

c. 2 and 3 only

Which of the following are methods of limiting the production of scattered radiation? 1. Using moderate ratio grids 2. Using the prone position for abdominal examinations 3. Restricting the field size to the smallest practical size Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

c. 2 and 3 only If a fairly large patient is turned prone, the abdominal measurement will be significantly different from the AP measurement as a result of the effect of compression. Thus, the part is essentially "thinner," and less scattered radiation will be produced. If the patient remains supine and a compression band is applied, a similar effect will be produced. Beam restriction is probably the single most effective means of reducing the production of scattered radiation. Grid ratio affects the cleanup of scattered radiation; it has no effect on the production of scattered radiation. (Shephard, p 203) #14886

Component part(s) of x-ray film include the following: 1. Phosphor layer 2. Gelatin emulsion 3. Adhesive layer Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

c. 2 and 3 only The manufacture of x-ray film starts with a clear polyester base that serves as support for the emulsion. Applied next is an adhesive layer that functions to hold the emulsion to the base. Next is the emulsion, consisting of silver halide grains suspended in gelatin. Finally, a supercoat of clear hard gelatin is applied as an antiabrasive layer. A phosphor layer is used in the construction of intensifying screens. (Shephard, pp 85 88)

An exposure was made using 600 mA and 18 ms. If the mA is changed to 400, which of the following exposure times would most closely approximate the original radiographic density? Select one: a. 16 ms b. 0.16 second c. 27 ms d. 0.27 second

c. 27 ms Since 18 ms is equal to 0.018 s, and since mA × time = mAs, the original mAs was 10.8. Now it is only necessary to determine what exposure time must be used with 400 mA to provide the same 10.8 mAs (and thus the same radiographic density). Because mA × time = mAs, 400x = 10.8 x = 0.027 second (27 milliseconds) (Selman, p 214) #15949

High-kilovoltage exposure factors are usually required for radiographic examinations using 1. water-soluble, iodinated media. 2. a negative contrast agent. 3. barium sulfate. Select one: a. 1 only b. 2 only c. 3 only d. 1 and 3 only

c. 3 only Positive-contrast medium is radiopaque; negative-contrast material is radioparent. Barium sulfate (radiopaque, positive-contrast material) is most frequently used for examinations of the intestinal tract, and high-kVp exposure factors are used to penetrate (to see through and behind) the barium. Water-based iodinated contrast media (Conray, Amipaque) are also positive-contrast agents. However, the K-edge binding energy of iodine prohibits the use of much greater than 70 kVp with these materials. Higher kVp values will obviate the effect of the contrast agent. Air is an example of a negative-contrast agent, and high-kVp factors are clearly not indicated. (Shephard, pp 200 201)

An exposure was made at a 36-inch SID using 12 mAs and 75 kVp with a 400-speed imaging system and an 8:1 grid. A second radiograph is requested with improved recorded detail. Which of the following groups of technical factors will best accomplish this task? Select one: a. 15 mAs, 12:1 grid, 75 kVp, 400-speed system, 36 inches SID b. 15 mAs, 12:1 grid, 75 kVp, 400-speed system, 40 inches SID c. 30 mAs, 12:1 grid, 75 kVp, 200-speed system, 40 inches SID d. 12 mAs, 8:1 grid, 86 kVp, 200-speed system, 36 inches SID

c. 30 mAs, 12:1 grid, 75 kVp, 200-speed system, 40 inches SID

A lateral radiograph of the cervical spine was made at 40 inches using 100 mA and 0.1-second exposure. If it is desired to increase the distance to 72 inches, what should be the new mA, all other factors remaining the same? Select one: a. 100 b. 200 c. 300 d. 400

c. 300

Which of the following groups of exposure factors will produce the longest scale of contrast? Select one: a. 200 mA, 0.08 second, 95 kVp, 12:1 grid b. 500 mA, 0.03 second, 81 kVp, 8:1 grid c. 300 mA, 0.05 second, 95 kVp, 8:1 grid d. 600 mA, 1/40 second, 70 kVp, 6:1 grid

c. 300 mA, 0.05 second, 95 kVp, 8:1 grid

Exposure factors of 80 kVp and 8 mAs are used for a particular nongrid exposure. What should be the new mAs if an 8:1 grid is added? Select one: a. 16 mAs b. 24 mAs c. 32 mAs d. 40 mAs

c. 32 mAs To change nongrid to grid exposure, or to adjust exposure when changing from one grid ratio to another, remember the factor for each grid ratio: No grid = 1 × original mAs 5:1 grid = 2 × original mAs 6:1 grid = 3 × original mAs 8:1 grid = 4 × original mAs 12:1 grid = 5 × original mAs 16:1 grid = 6 × original mAs Therefore, to change from nongrid exposure to an 8:1 grid, multiply the original mAs by a factor of 4. A new mAs of 32 is required. (Saia, p 324) #15987

Which of the following groups of exposure factors would be most appropriate to control involuntary motion? Select one: a. 400 mA, 0.03 second b. 200 mA, 0.06 second c. 600 mA, 0.02 second d. 100 mA, 0.12 second

c. 600 mA, 0.02 second

If 92 kV and 12 mAs were used for a particular abdominal exposure with single-phase equipment, what mAs would be required to produce a similar radiograph with three-phase, six-pulse equipment? Select one: a. 36 b. 24 c. 8 d. 6

c. 8

A particular radiograph was produced using 6 mAs and 110 kVp with an 8:1 ratio grid. The radiograph is to be repeated using a 16:1 ratio grid. What should be the new mAs? Select one: a. 3 b. 6 c. 9 d. 12

c. 9

The violet light emited by the photostimulable phosphor (PSP) is transformed into the image seen on the CRT by the Select one: a. PSP. b. scanner-reader. c. ADC. d. helium-neon laser.

c. ADC. The exposed CR cassette is placed into the CR scanner reader, where the PSP/imaging plate is automatically removed. The latent image appears as the PSP is scanned by a narrow high-intensity helium-neon laser to obtain the pixel data. As the plate is scanned in the CR reader, it releases a violet light a process referred to as photo-stimulated luminescence. The luminescent light is converted to electrical energy representing the analog image. The electrical energy is sent to an analog-to-digital converter (ADC) where it is digitized and becomes the digital image that is eventually displayed (after a short delay) on a high-resolution monitor and/or printed out by a laser printer. The digitized images can also be manipulated in postprocessing, electronically transmitted, and stored/archived. (

Although the stated focal spot size is measured directly under the actual focal spot, focal spot size in fact varies along the length of the x-ray beam. At which portion of the x-ray beam is the effective focal spot the largest? Select one: a. At its outer edge b. Along the path of the central ray c. At the cathode end d. At the anode end

c. At the cathode end

Although the stated focal spot size is measured directly under the actual focal spot, focal spot size really varies along the length of the x-ray beam. At which portion of the x-ray beam is the effective focal spot the largest? Select one: a. At its outer edge b. Along the path of the central ray c. At the cathode end d. At the anode end

c. At the cathode end

Which of the following terms is used to describe unsharp edges of tiny radiographic details? Select one: a. Diffusion b. Mottle c. Blur d. Umbra

c. Blur

All of the following statements regarding CR cassettes are true, except Select one: a. CR cassettes do not contain radiographic film. b. CR cassettes use no intensifying screens. c. CR cassettes must exclude all white light. d. CR cassettes function to protect the IP (image plate).

c. CR cassettes must exclude all white light. Externally, CR (computed radiography) cassettes appear very much like traditional film-screen cassettes. However, the main function of a CR cassette is to support and protect the IP that lies within the CR cassettes. CR cassettes do not contain intensifying screens or film and therefore do not need to be light tight. The photostimulable IP is not affected by light. (Shephard, p 51) #15007

Which of the following radiographic accessories functions to produce uniform density on a radiograph? Select one: a. Grid b. Intensifying screens c. Compensating filter d. Penetrometer

c. Compensating filter

What is the best way to reduce magnification distortion? Select one: a. Use a small focal spot. b. Increase the SID. c. Decrease the OID. d. Use a slow screen-film combination.

c. Decrease the OID.

What effect will a stained intensifying screen have on the finished radiograph? Select one: a. Blurring b. Magnification c. Decreased density d. Increased density

c. Decreased density

Which of the following is the correct order of radiographic film processing? Select one: a. Developer, wash, fixer, dry b. Fixer, wash, developer, dry c. Developer, fixer, wash, dry d. Fixer, developer, wash, dry

c. Developer, fixer, wash, dry

Which of the following pathologic conditions would require a decrease in exposure factors? Select one: a. Congestive heart failure b. Pneumonia c. Emphysema d. Pleural effusion

c. Emphysema Emphysema is abnormal distention of the pulmonary alveoli (or tissue spaces) with air. The presence of abnormal amounts of air makes a decrease from normal exposure factors necessary to avoid excessive density. Congestive heart failure, pneumonia, and pleural effusion, all involve abnormal amounts of fluid in the chest and would therefore require an increase in exposure factors. (Carlton & Adler, p 258)

What information, located on each box of film, is important to note and has a direct relationship to image quality? Select one: a. Number of films in the box b. Manufacturer's name c. Expiration date d. Emulsion lot

c. Expiration date

Which of the following can affect the amount of developer replenisher delivered per film in an automatic processor? Select one: a. Developer temperature b. Amount of film exposure c. Film size d. Processor capacity

c. Film size

Why are a single intensifying screen and single emulsion film used for select radiographic examinations? Select one: a. To decrease patient dose b. To achieve longer-scale contrast c. For better recorded detail d. To decrease fiscal expenses

c. For better recorded detail The diffusion of fluorescent light from intensifying screens is responsible for a loss of recorded detail on double-emulsion film. Therefore, by changing the system to include only one intensifying screen and single-emulsion film, as in mammographic systems, light diffusion is reduced and better recorded detail results. Patient dose is somewhat greater than with a two-screen cassette system, but the advantage of significantly improved recorded detail greatly offsets this. (Shephard, p 49) #15079

In which of the following examinations should 70 kVp not be exceeded? Select one: a. Upper GI (UGI) b. Barium enema (BE) c. Intravenous urogram (IVU) d. Chest

c. Intravenous urogram (IVU) The iodine-based contrast material used in intravenous (IV) urography gives optimum opacification at 60 to 70 kVp. Use of higher kVp will negate the effect of the contrast medium; a lower contrast will be produced, and poor visualization of the renal collecting system will result. GI and BE examinations employ high-kVp exposure factors (about 120 kVp) to penetrate through the barium. In chest radiography, high-kVp technical factors are preferred for maximum visualization of pulmonary vascular markings, made visible with long-scale contrast. (Saia, p 347) #14966

In which of the following examinations would a cassette front with very low absorption properties be especially desirable? Select one: a. Extremity radiography b. Abdominal radiography c. Mammography d. Angiography

c. Mammography

Film base is currently made of which of the following materials? Select one: a. Cellulose nitrate b. Cellulose acetate c. Polyester d. Glass

c. Polyester

Which of the following has the greatest effect on radiographic density? Select one: a. Aluminum filtration b. Kilovoltage c. SID d. Scattered radiation

c. SID

Which of the following chemicals is used in the production of radiographic film emulsion? Select one: a. Sodium sulfite b. Potassium bromide c. Silver halide d. Chrome alum

c. Silver halide

Why is a very short exposure time essential in chest radiography? Select one: a. To avoid excessive focal spot blur b. To maintain short-scale contrast c. To minimize involuntary motion d. To minimize patient discomfort

c. To minimize involuntary motion

The rate of chemical replenishment in automatic processing is based on Select one: a. solution temperature. b. processor speed. c. amount of film processed. d. solution agitation.

c. amount of film processed.

The fact that x-ray intensity across the primary beam can vary as much as 45% describes the Select one: a. line focus principle. b. transformer law. c. anode heel effect. d. inverse square law.

c. anode heel effect.

The reduction in x-ray photon intensity as the photon passes through material is termed Select one: a. absorption. b. scattering. c. attenuation. d. divergence.

c. attenuation.

Because of the anode heel effect, the intensity of the x-ray beam is greatest along the Select one: a. path of the central ray. b. anode end of the beam. c. cathode end of the beam. d. transverse axis of the IR.

c. cathode end of the beam.

The processor rollers that are out of solution and function to transfer the film from one solution to another are the Select one: a. deflector plates. b. guide shoes. c. crossover rollers. d. turnaround assembly.

c. crossover rollers.

The microswitch for controlling the amount of replenishment used in an automatic processor is located at the Select one: a. receiving bin. b. crossover roller. c. entrance roller. d. replenishment pump.

c. entrance roller.

The absorption of useful radiation by a grid is called Select one: a. grid selectivity. b. contrast improvement factor. c. grid cutoff. d. latitude.

c. grid cutoff.

The cause of films coming from the automatic processor still damp can be Select one: a. air velocity too high. b. unbalanced processing temperatures. c. insufficient hardening action. d. underreplenishment.

c. insufficient hardening action.

Materials that emit light when stimulated by x-ray photons are called Select one: a. ions. b. electrodes. c. phosphors. d. crystals.

c. phosphors. Materials that emit light when stimulated by x-ray photons are called phosphors. Phosphors are used in intensifying screens, where they function to absorb x-ray photon energy and convert it to visible light energy. Typically, for each x-ray photon absorbed, many light photons are emitted; intensifying screens serve to amplify the action of x-rays. (Carlton & Adler, p 330)

That portion of a CR cassette that records the radiologic image is the Select one: a. emulsion. b. helium-neon laser. c. photostimulable phosphor. d. scanner-reader.

c. photostimulable phosphor.

A particular mAs, regardless of the combination of mA and time, will reproduce the same radiographic density. This is a statement of the Select one: a. line focus principle. b. inverse square law. c. reciprocity law. d. law of conservation of energy.

c. reciprocity law.

The function of the developer solution chemicals is to Select one: a. reduce the manifest image to a latent image. b. increase production of silver halide crystals. c. reduce the latent image to a manifest image. d. remove the unexposed crystals from the film.

c. reduce the latent image to a manifest image.

Slow-speed screens are used Select one: a. to minimize patient dose. b. to keep exposure time to a minimum. c. to image fine anatomic details. d. in pediatric radiography.

c. to image fine anatomic details.

What pixel size has a 2048 × 2048 matrix with an 80-cm FOV? Select one: a. 0.04 mm b. 0.08 mm c. 0.2 mm d. 0.4 mm

d. 0.4 mm

A quality assurance program serves to 1. keep patient dose to a minimum. 2. keep radiographic quality consistent. 3. ensure equipment efficiency. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

A technique chart should include which of the following information? 1. Recommended SID 2. Grid ratio 3. Screen-film combination Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Acceptable method(s) of minimizing motion unsharpness is (are) 1. suspended respiration. 2. short exposure time. 3. patient instruction. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Base-plus fog is a result of 1. blue-tinted film base. 2. chemical development. 3. the manufacturing process. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Chemical fog may be attributed to 1. excessive developer temperature. 2. oxidized developer. 3. excessive replenishment. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Compression of the breast during mammographic imaging improves the technical quality of the image because 1. geometric blurring is decreased. 2. less scattered radiation is produced. 3. patient motion is reduced. Select one: a. 1 only b. 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Conditions contributing to poor radiographic film archival quality include 1. fixer retention. 2. insufficient developer replenishment. 3. poor storage conditions. Select one: a. 1 only b. 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Disadvantage(s) of using low kV technical factors include: 1. insufficient penetration. 2. increased patient dose. 3. diminished latitude. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Factor(s) that can be used to regulate radiographic density is (are) 1. milliamperage. 2. exposure time. 3. kilovoltage. Select one: a. 1 only b. 2 only c. 1 and 2 only d. 1, 2, and 3

d. 1, 2, and 3

Factors that contribute to film fog include 1. the age of the film. 2. excessive exposure to safelight. 3. processor chemistry. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Geometric unsharpness is influenced by which of the following? 1. Distance from object to image 2. Distance from focus to object 3. Distance from focus to image Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

In comparison to 60 kVp, 80 kVp will 1. permit greater exposure latitude. 2. produce longer scale contrast. 3. produce more scattered radiation. Select one: a. 1 only b. 2 only c. 1 and 2 only d. 1, 2, and 3

d. 1, 2, and 3

In which of the following ways can higher radiographic contrast be obtained in abdominal radiography? 1. By using lower kilovoltage 2. By using a contrast medium 3. By limiting the field size Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Shape distortion is influenced by the relationship between the 1. x-ray tube and the part to be imaged. 2. part to be imaged and the image recorder. 3. image recorder and the x-ray tube. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Silver reclamation may be accomplished in which of the following ways? 1. Metallic replacement cartridge 2. Electrolytic plating unit 3. Removal from used film Select one: a. 1 only b. 2 only c. 1 and 2 only d. 1, 2, and 3

d. 1, 2, and 3

The advantage(s) of high kilovoltage chest radiography is (are) that 1. exposure latitude is increased. 2. it produces long-scale contrast. 3. it reduces patient dose. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

The darkroom should be constructed and equipped so as to avoid 1. external light leaks. 2. film bin light leaks. 3. safelight fog. Select one: a. 1 only b. 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

The functions of the automatic processor's recirculation system include 1. keeping the solution in contact with the film emulsion. 2. maintaining uniform temperatures. 3. mixing and agitating solutions Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

The functions of the automatic processor's roller system include 1. film transport. 2. agitation. 3. squeegee action. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following adult radiographic examinations usually require(s) use of a grid? 1. Ribs 2. Vertebrae 3. Shoulder Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following can affect histogram appearance? 1. Centering accuracy 2. Positioning accuracy 3. Processing algorithm accuracy Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following can affect radiographic contrast? 1. Processing 2. Pathology 3. OID Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following can cause poor screen-film contact? 1. Damaged image receptor frame 2. Foreign body in image receptor 3. Warped image receptor front Select one: a. 1 only b. 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following contribute to the radiographic contrast present on the finished radiograph? 1. Atomic number of tissues radiographed 2. Any pathologic processes 3. Degree of muscle development Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following contribute to the radiographic contrast present on the finished radiograph? 1. Tissue density 2. Pathology 3. Muscle development Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following factors influence(s) the production of scattered radiation? 1. Kilovoltage level 2. Tissue density 3. Size of field Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following influences geometric unsharpness? 1. OID 2. Source-object distance 3. SID Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following is (are) tested as part of a QA program? 1. Beam alignment 2. Reproducibility 3. Linearity Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following may be used to reduce the effect of scattered radiation on the finished radiograph? 1. Grids 2. Collimators 3. Compression bands Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following pathologic conditions require(s) a decrease in exposure factors? 1. Pneumothorax 2. Emphysema 3. Multiple myeloma Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

Which of the following will influence recorded detail? 1. Screen speed 2. Screen-film contact 3. Focal spot Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3

The decision as to whether to deliver ionic or nonionic contrast media should include a preliminary patient history including, but not limited to, 1. patient age. 2. history of respiratory disease. 3. history of cardiac disease. Select one: a. 1 and 2 b. 1 and 3 c. 2 and 3 d. 1, 2, and 3

d. 1, 2, and 3 All of the choices listed in the question should be part of a preliminary patient history before deciding to inject ionic or nonionic contrast media. As patients age, their general health decreases, and they are therefore more likely to suffer from adverse reactions. Patients with a history of respiratory disease, such as asthma or emphysema and chronic obstructive pulmonary disease (COPD), are more likely to have a reaction, and to suffer greater distress in the event of a reaction. Patients with cardiac disease run an increased risk of changes in heart rate and myocardial infarction. Patients should also be screened for decreased renal or hepatic function, sickle-cell disease, diabetes, and pregnancy. (Adler & Carlton, pp 314 317)

Which of the following pathologic conditions are considered additive conditions with respect to selection of exposure factors? 1. Osteoma 2. Bronchiectasis 3. Pneumonia Select one: a. 1 and 2 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 All these conditions are considered technically additive because they all involve an increase in tissue density. Osteoma, or exostosis, is a (usually benign) bony tumor that can develop on bone. Bronchiectasis is a chronic dilatation of the bronchi with accumulation of fluid. Pneumonia is inflammation of the lung(s) with accumulation of fluid. Additional bony tissues and the pathological presence of fluid are additive pathological conditions and require an increase in exposure factors. Destructive conditions such as osteoporosis require a decrease in exposure factors. (Carlton & Adler, p 258)

An increase in exposure factors is usually required in which of the following circumstances? 1. Edema 2. Ascites 3. Acromegaly Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 An increase in exposure factors will be required when imaging pathological conditions that cause greater attenuation of the x-ray beam. The x-ray beam suffers more attenuation as the thickness and/or density of the tissues increases. Examples include conditions involving an increase in part size as a result of fluid accumulation (edema) following trauma, an accumulation of fluid in the abdomen (ascites), or an increase in bone size and density (acromegaly) as a result of an endocrine disorder. The radiographer needs a good working knowledge of pathological conditions, their effect on the body, and the resulting modifications in technical factors required. (Carlton & Adler, p 258) #15946

X-ray photon beam attenuation is influenced by 1. tissue type. 2. subject thickness. 3. photon quality. Select one: a. 1 only b. 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 Attenuation (decreased intensity through scattering or absorption) of the x-ray beam is a result of its original energy and its interactions with different types and thicknesses of tissue. The greater the original energy/quality (the higher the kilovoltage) of the incident beam, the less the attenuation. The greater the effective atomic number of the tissues (tissue type determines absorbing properties), the greater the beam attenuation. The greater the volume of tissue (subject density and thickness), the greater the beam attenuation. (Bushong, p 185) #15077

The effect described as differential absorption is 1. responsible for radiographic contrast. 2. a result of attenuating characteristics of tissue. 3. minimized by the use of high kVp. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 Differential absorption refers to the x-ray absorption characteristics of neighboring anatomic structures. The radiographic representation of these structures is referred to as radiographic contrast; it may be enhanced with high-contrast technical factors, especially using low kilovoltage levels. At low kilovoltage levels, the photoelectric effect predominates. (Bushong, pp 181 184)

Distortion can be caused by 1. tube angle. 2. the position of the organ or structure within the body. 3. the radiographic positioning of the part. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 Distortion is caused by improper alignment of the tube, body part, and image recorder. Anatomic structures within the body are rarely parallel to the IR in a simple recumbent position. In an attempt to overcome this distortion, we position the part to be parallel with the IR, or angle the central ray to "open up" the part. Examples of this technique are obliquing the pelvis to place the ilium parallel to the IR, or angling the central ray cephalad to "open up" the sigmoid colon. (Shephard, pp 228 234) #15115

Which of the following factors contribute(s) to the efficient performance of a grid? 1. Grid ratio 2. Number of lead strips per inch 3. Amount of scatter transmitted through the grid Select one: a. 1 only b. 2 only c. 1 and 2 only d. 1, 2, and 3

d. 1, 2, and 3 Grid ratio is defined as the ratio of the height of the lead strips to the width of the interspace material; the higher the lead strips, the more scattered radiation they will trap and the greater the grid's efficiency. The greater the number of lead strips per inch, the thinner and less visible they will be on the finished radiograph. The function of a grid is to absorb scattered radiation in order to improve radiographic contrast. The selectivity of a grid is determined by the amount of primary radiation transmitted through the grid divided by the amount of scattered radiation transmitted through the grid. (Selman, pp 236 237) #15023

Which of the following is (are) characteristic(s) of a 16:1 grid? 1. It absorbs a high percentage of scattered radiation. 2. It has little positioning latitude. 3. It is used with high-kVp exposures. Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 High-kilovoltage exposures produce large amounts of scattered radiation, and therefore high-ratio grids are used in an effort to trap more of this scattered radiation. However, accurate centering and positioning become more critical to avoid grid cutoff. (Selman, p 243) #15055

Which of the following is (are) method(s) that would enable the radiographer to reduce the exposure time required for a particular radiograph? 1. Use higher mA. 2. Use higher kVp. 3. Use faster film-screen combination. Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 If it is desired to reduce the exposure time for a particular radiograph, as it might be when radiographing those who are unable to cooperate fully, the milliamperage must be increased sufficiently to maintain the original mAs, and thus radiographic density. A higher kilovoltage could be useful because it would allow further reduction of the mAs (exposure time) according to the 15% rule. Use of a higher-speed film-screen combination also helps reduce mAs (exposure time) through more efficient conversion of photon energy to fluorescent light energy. (Selman, pp 182, 214)

Greater latitude is available to the radiographer in which of the following circumstances? 1. Using high-kVp technical factors 2. Using a slow film-screen combination 3. Using a low-ratio grid Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 In the low kilovoltage ranges, a difference of just a few kVp makes a very noticeable radiographic difference. High-kVp technical factors offer much greater margin for error, as do slow film-screen combinations. Lower-ratio grids offer more tube-centering latitude than high-ratio grids. (Saia, p 360) #14930

To be suitable for use in intensifying screens, a phosphor should have which of the following characteristics? 1. High conversion efficiency 2. High x-ray absorption 3. High atomic number Select one: a. 1 only b. 3 only c. 1 and 2 only d. 1, 2, and 3

d. 1, 2, and 3 Intensifying-screen phosphors that have a high atomic number are more likely to absorb a high percentage of the incident x-ray photons and convert x-ray photon energy to fluorescent light energy. How efficiently the phosphors detect and interact with the x-ray photons is termed quantum detection efficiency. How effectively the phosphors make this energy conversion is termed conversion efficiency.(Shephard, p 65)

Which of the following is (are) associated with subject contrast? 1. Patient thickness 2. Tissue density 3. Kilovoltage Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 Radiographic contrast is the sum of film emulsion contrast and subject contrast. Subject contrast has by far the greatest influence on radiographic contrast. Several factors influence subject contrast, each as a result of beam attenuation differences in the irradiated tissues. As patient thickness and tissue density increase, attenuation increases and subject contrast is increased. As kilovoltage increases, higher energy photons are produced, beam attenuation is decreased, and subject contrast decreases. (Carlton & Adler, pp 387 389) #15095

Recommended method(s) of minimizing motion unsharpness include 1. suspended respiration. 2. short exposure time. 3. patient instruction. Select one: a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 The shortest possible exposure time should be used to minimize motion unsharpness. Motion causes unsharpness that destroys detail. Careful and accurate patient instruction is essential for minimizing voluntary motion. Suspended respiration eliminates respiratory motion. Using the shortest possible exposure time is essential to decreasing involuntary motion. Immobilization can also be useful in eliminating motion unsharpness. (Selman, p 210) #15939

What determines the amount of fluorescent light emitted from a fluorescent screen? 1. Thickness of the active layer 2. Type of phosphor used 3. kV range used for exposure Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 The thicker the active layer of phosphors, the more fluorescent light is emitted from the screen. Different types of phosphors have different conversion efficiencies; rare earth phosphors emit more light during a given exposure than do calcium tungstate phosphors. As the kVp level is increased, so is the amount of fluoroscopic light emitted by intensifying screen phosphors. (Selman, pp 177 182) #15942

What determines the quantity of fluorescent light emitted from a fluorescent screen? 1. Thickness of the phosphor layer 2. Type of phosphor used 3. kV range used for exposure Select one: a. 1 only b. 1 and 2 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 The thicker the layer of phosphors, the more fluorescent light is emitted from the screen. Different types of phosphors have different conversion efficiencies; rare earth phosphors emit more light during a given exposure than do calcium tungstate phosphors. As the kVp level is increased, so is the amount of fluoroscopic light emitted by intensifying-screen phosphors. (Selman, pp 181 183) #14935

Characteristics of digital radiographic imaging include 1. solid state detector receptor plates. 2. direct-capture imaging system. 3. immediate image display. Select one: a. 1 only b. 1 and 3 only c. 2 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 Whereas CR utilizes traditional x-ray devices to enclose and protect the PSP image plate, digital radiography requires the use of somewhat different equipment. DR does not use cassettes or a traditional x-ray table; it is a direct-capture system of x-ray imaging. DR uses solid state detector plates as the x-ray image receptor (instead of a cassette in the Bucky tray) to intercept the collimated x-ray beam and form the latent image. The solid state detector plates are made of barium fluorohalide compounds similar to that used in CR's PSP image plates. DR affords the advantage of immediate display of the image,compared to CR's delayed image display. (Shephard, p 335)

If 300 mA has been selected for a particular exposure, what exposure time would be required to produce 60 mAs? Select one: a. 1/60 second b. 1/30 second c. 1/10 second d. 1/5 second

d. 1/5 second

If a particular grid has lead strips 0.40 mm thick, 4.0 mm high, and 0.25 mm apart, what is its grid ratio? Select one: a. 8:1 b. 10:1 c. 12:1 d. 16:1

d. 16:1 Grid ratio is defined as the ratio between the height of the lead strips and the width of the distance between them (ie, their height divided by the distance between them). If the height of the lead strips is 4.0 mm and the lead strips are 0.25 mm apart, the grid ratio must be 16:1 (4.0 divided by 0.25). The thickness of the lead strip is unrelated to grid ratio. (Selman, p 236) #15090

Which of the following examinations might require the use of 120 kVp? 1. AP abdomen 2. Chest radiograph 3. Barium-filled stomach Select one: a. 1 only b. 2 only c. 1 and 2 only d. 2 and 3 only

d. 2 and 3 only

If the quantity of black metallic silver on a particular radiograph is such that it allows 1% of the illuminator light to pass through the film, that film has a density of Select one: a. 0.01. b. 0.1. c. 1.0. d. 2.0.

d. 2.0.

If the quantity of black metallic silver on a particular radiograph is such that it allows 1% of the illuminator light to pass through the image, that image has a density of Select one: a. 0.01. b. 0.1. c. 1.0. d. 2.0.

d. 2.0.

Using a 48-inch SID, how much object-image distance (OID) must be introduced to magnify an object two times? Select one: a. 8-inch OID b. 12-inch OID c. 16-inch OID d. 24-inch OID

d. 24-inch OID Magnification radiography may be used to delineate a suspected hairline fracture or to enlarge tiny, contrast-filled blood vessels. It also has application in mammography. To magnify an object to twice its actual size, the part must be placed midway between the focal spot and the IR. (Selman, pp 223 225; Shephard, pp 229 231)

Which of the following groups of exposure factors would be most effective in eliminating prominent pulmonary vascular markings in an RAO position of the sternum? Select one: a. 500 mA, 1/30 second, 70 kVp b. 200 mA, 0.04 second, 80 kVp c. 300 mA, 1/10 second, 80 kVp d. 25 mA, 7/10 second, 70 kVp

d. 25 mA, 7/10 second, 70 kVp In the RAO position, the sternum must be visualized through the thorax and heart. Prominent pulmonary vascular markings can hinder good visualization. A method frequently used to overcome this problem is to use an mAs with a long exposure time. The patient is permitted to breathe normally during the (extended) exposure and, by doing so, blurs out the prominent vascularities. (Ballinger & Frank, vol 1, p 474) #15073

If 0.05 second was selected for a particular exposure, what mA would be necessary to produce 15 mAs? Select one: a. 900 b. 600 c. 500 d. 300

d. 300

The exposure factors used for a particular nongrid radiograph were 400 mA, 0.02 second, and 90 kVp. Another radiograph using an 8:1 grid is requested. Which of the following groups of factors is most appropriate? Select one: a. 400 mA, 0.02 second, 110 kVp b. 200 mA, 0.08 second, 90 kVp c. 300 mA, 0.05 second, 100 kVp d. 400 mA, 0.08 second, 90 kVp

d. 400 mA, 0.08 second, 90 kVp The addition of a grid will help clean up the scattered radiation produced by higher kVp, but it requires an mAs adjustment. According to the grid conversion factors listed here, the addition of an 8:1 grid requires that the original mAs be multiplied by a factor of 4: No grid = 1 × the original mAs 5:1 grid = 2 × the original mAs 6:1 grid = 3 × the original mAs 8:1 grid = 4 × the original mAs 12:1 (or 10:1) grid = 5 × the original mAs 16:1 grid = 6 × the original mAs The adjustment therefore requires 32 mAs at 90 kVp. (Saia, p 328) #14884

The developer temperature in a 90-second automatic processor is usually about Select one: a. 75° to 80°F. b. 80° to 85°F. c. 85° to 90°F. d. 90° to 95°F.

d. 90° to 95°F.

How is SID related to exposure rate and radiographic density? Select one: a. As SID increases, exposure rate increases and radiographic density increases. b. As SID increases, exposure rate increases and radiographic density decreases. c. As SID increases, exposure rate decreases and radiographic density increases. d. As SID increases, exposure rate decreases and radiographic density decreases.

d. As SID increases, exposure rate decreases and radiographic density decreases.

Which of the following conditions will require an increase in x-ray photon energy/penetration? Select one: a. Fibrosarcoma b. Osteomalacia c. Paralytic ileus d. Ascites

d. Ascites

Which of the following pathologic conditions would require an increase in exposure factors? Select one: a. Pneumoperitoneum b. Obstructed bowel c. Renal colic d. Ascites

d. Ascites

Which of the following possesses the widest dynamic range? Select one: a. high-speed screens b. slow-speed screens c. AEC d. CR

d. CR One of the biggest advantages of CR is the dynamic range, or latitude, it offers. The characteristic curve of x-ray film emulsion has a certain "range of correct exposure," limited by the toe and shoulder of the curve. In CR, there is a linearrelationship between the exposure, given the PSP (photostimulable phosphor, or image plate) and its resulting luminescence, as it is scanned by the laser. This affords much greater exposure latitude and technical inaccuracies can be effectively eliminated. Overexposure of up to 500% and underexposure of up to 80% are reported as recoverable, thus eliminating most retakes. This surely affords increased efficiency; however, this does not mean that images can be exposed arbitrarily. The radiographer must keep dose reduction in mind. The same exposure factors as screen-film systems, or less, are generally recommended for CR. Intensifying screens used in screen-film x-ray imaging tend to produce high contrast. The faster the screens, the higher the contrast; higher contrast is often associated with decreased latitude. AEC refers to automatic exposure control and is unrelated to dynamic range or latitude. (Ballinger & Frank, vol 3, p 234; Shephard, pp 336 338)

Focusing distance is associated with which of the following? Select one: a. Computed tomography b. Chest radiography c. Magnification radiography d. Grids

d. Grids

What should be done to correct for magnification when using air-gap technique? Select one: a. Decrease OID b. Increase OID c. Decrease SID d. Increase SID

d. Increase SID

Which of the following functions to increase the mA? Select one: a. Increasing the speed of anode rotation b. Increasing the transformer turns ratio c. Using three-phase rectification d. Increasing the heat of the filament

d. Increasing the heat of the filament

Which of the following is an abnormal intensifying screen action? Select one: a. Fluorescence b. Luminescence c. Speed d. Lag

d. Lag

Underexposure of a radiograph can be caused by all of the following except insufficient Select one: a. mA. b. exposure time. c. kVp. d. SID.

d. SID.

Which of the following is performed to check the correctness of the developing parameters? Select one: a. Densitometry b. A thorough cleaning of rollers c. A warm-up procedure d. Sensitometry

d. Sensitometry Sensitometry is a method of quality control for daily monitoring of the automatic film processor. A densitometer is a device used to read optical density. Crossover rollers should be cleaned daily to prevent the buildup of crystallized solution on the rollers. A warm-up procedure is performed on an x-ray tube for safe operation after prolonged disuse. (Selman, pp 292 293) #14988

How is the mAs adjusted in an AEC system as the film screen speed combination is decreased? Select one: a. The mAs increases as film screen speed decreases. b. Both the mAs and the kVp increase as film screen speed decreases. c. The mAs decreases as film screen speed decreases. d. The mAs remains unchanged as film screen speed decreases.

d. The mAs remains unchanged as film screen speed decreases.

What is the purpose of the thin layer of lead that is often located behind the rear intensifying screen in a image receptor? Select one: a. To prevent crossover b. To increase screen speed c. To diffuse light photons d. To prevent scattered radiation fog

d. To prevent scattered radiation fog

When the collimated field must extend past the edge of the body, allowing primary radiation to strike the tabletop, as in a lateral lumbar spine, what may be done to prevent excessive radiographic density due to undercutting? Select one: a. Reduce the mAs b. Reduce the kVp c. Use a shorter SID d. Use lead rubber to absorb tabletop primary radiation

d. Use lead rubber to absorb tabletop primary radiation

Geometric unsharpness is most likely to be greater Select one: a. at long SIDs. b. at the anode end of the image. c. with small focal spots. d. at the cathode end of the image.

d. at the cathode end of the image.

A radiograph made with a parallel grid demonstrates decreased density on its lateral edges. This is most likely due to Select one: a. static electrical discharge. b. the grid being off-centered. c. improper tube angle. d. decreased SID.

d. decreased SID.

All of the following affect the exposure rate of the primary beam except Select one: a. mA. b. kVp. c. distance. d. field size.

d. field size.

All of the following have an impact on radiographic contrast, except Select one: a. photon energy. b. grid ratio. c. OID. d. focal spot size.

d. focal spot size.

All of the following are related to recorded detail except Select one: a. motion. b. film-screen contact. c. SID. d. grid ratio.

d. grid ratio.

A film emulsion having wide latitude is likely to exhibit Select one: a. high density. b. low density. c. high contrast. d. low contrast.

d. low contrast.

A change from 100 speed screens to 200 speed screens would require what change in mAs? Select one: a. mAs should be increased by 15%. b. mAs should be increased by 30%. c. mAs should be doubled. d. mAs should be halved.

d. mAs should be halved.

The major function of filtration is to reduce Select one: a. image noise. b. scattered radiation. c. operator dose. d. patient dose.

d. patient dose.

Treelike, branching black marks on a radiograph are usually the result of Select one: a. bending the film acutely. b. improper development. c. improper film storage. d. static electricity.

d. static electricity.


संबंधित स्टडी सेट्स

How Much You Can Expect to Borrow

View Set

Algebra II 5.02: Solve Radical Equations

View Set

Module 31- Stress, Coping, Anxiety

View Set

NBCOT Musculoskeletal Impairments Exam Prep

View Set