RAD Image and Evaluation Final

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Input phosphor

- labeled A

Photocathode

- labeled D

Electrostatic lens

- labeled F

What is the minimum amount of lead aprons a radiographer should have on a portable?

2

A radiograph made using 300 mA, 0.10 seconds, and 75 kVp exhibits motion unsharpness but otherwise satisfactory technical quality. The radiograph must be repeated using a shorter exposure time. Which of the following exposure times will maintain the original plate exposure if the kVp is increased to 86 and the mA is increased to 400? A. 0.0375 sec B. 0.05 sec C. 0.10 sec D. 0.25 sec

A. 0.0375

The normal milliamperage used for image intensified fluoroscopy is about: A. 0.5-5. mA B. 10-15 mA C. 25-100 mA D. 100-600 mA

A. 0.5-5 mA

Which of the following sets of technical factors will produce the LOWEST radiographic exposure? ' A. 100 mA, 0.050 sec B. 200 mA, 0.040 sec C. 400 mA, 0.050 sec D. 600 mA, 0.030 sec

A. 100 mA, 0.050 sec

If the input screen of an image intensifier measures 24 cm and the output screen measures 2.0 cm, the minification gain would be a factor of: A. 144 B. 48 C. 12 D. .0069

A. 144

The geometric sharpness of an image is BEST when using: A. 180 cm SID B. 100 cm SID C. 80 cm SID D. 50 cm SID

A. 180 cm SID

A radiograph with few shades of gray, primarily exhibiting black and white areas only, would be described as having what type of contrast: 1. Long scale 2. short scale 3. low 4. high A. 2 and 4 B. 1 and 3 C. 1 and 4 D. 2 only

A. 2 and 4

Advantages of digital acquisition fluoroscopy as compared to standard image intensified fluoroscopy include: 1. less image distortion 2. higher image resolution 3. lower occupational exposure A. 3 only B. 1 and 2 only C. 2 and 3 only D. 1, 2 and 3

A. 3 only

The geometric properties of radiographic image quality include: 1. contrast 2. density 3. detail A. 3 only B. 1 and 2 only C. 1 and 3 only D. 2 and 3 only

A. 3 only

The geometric properties of radiographic image quality include: 1. contrast 2. density 3. detail A. 3 only B. 1 and 2 only C. 1 and 3 only D. 2 and 3 only

A. 3 only

A radiographic image is produced by using 12 mAs and 92 kVp. Which combination of technical factors would maintain the original IR exposure/density? A. 6 mAs, 106 kVp B. 48 mAs, 78 kVp C. 48 mAs, 56 kVp D. 12 mAs, 78 kVp

A. 6 mAs, 106 kVp

A given radiographic technique (35 mAs/75 kVp) results in an IR exposure of 24.5 mR at a distance of 100 cm. The IR exposure for the same technical factors at 180 cm would be: A. 7.56 mR B. 13.61 mR C. 41.10 mR D. 79.38 mR

A. 7.56 mR

Change from 12:1 grid to a 5:1 grid will result in: A. IR exposure/density increased B. IR exposure/density decreased C. No visible change in IR exposure/density

A. IR exposure/density increased

Increase from 60 to 78 kVp will result in: A. IR exposure/density increased B. IR exposure/density decreased C. No visible change in IR exposure/density

A. IR exposure/density increased

The amount of magnification on a radiographic image can be determined by the formula: A. MF = SID/SOD B. MF = OID/SOD C. MF = SOD/OID D. none of the above

A. MF = SID/SOD

Which of the following systems adjusts the mA, kVp and/or pulse rate to compensate for changing patient/part thickness during fluoroscopy? A. automatic brightness control B. minification gain C. automatic resolution D. pin cushion correction

A. automatic brightness control

The arm that supports the equipment suspended over the patients table during image intensified fluoroscopy is called the: A. carriage B. gantry C. goose-neck D. o-arm

A. carriage

Decrease field size from 14x17 to 8x10 inches will cause: A. contrast increased B. contrast decreased C. no visible change in contrast

A. contrast increased

What is the relationship between kilovolt age and radiographic exposure? A. direct but not proportionate B. inverse, but not proportionate C. directly proportionate D. inversely proportionate

A. direct but not proportionate

The photocathode layer that helps to convert x-rays into an electronic signal in the image intensification tube is located on the ____________ of the tube. A. input side B. output side C. periphery D. focal tract

A. input side

Foreshortening of an anatomic structure means that: A. it is projected on the image receptor smaller than its actual size B. its image is more lengthened than its actual size C. it is accompanied by an increase in contrast D. it is significantly magnified

A. it is projected on the image receptor smaller than its actual size

The image of a body part comprised of structures with minimal differential attenuation will appear to have: A. low contrast B. high density C. high magnification D. high contrast

A. low contrast

During digital acquisition and processing of a radiographic image, large objects are represented by: A. Low spatial frequency B. High spatial frequency C. Nyquist signal D. Pythagorean signal

A. low-spatial frequency signal

Which of the following units is used to express image resolution? A. lp/mm B. mrem C. kev D. cm

A. lp/mm

Which set of technical factors will produce an image with the longest scale of contrast? mAs kV SID Grid A. 20 92 40" 5:1 B. 24 72 40" 8:1 C. 18 92 40" 10:1 D. 34 66 40" 10:1

A. mAs: 20 kV: 92 SID: 40" Grid: 5:1

The squared ratio of the input to the output screen diameter in an image intensifier tube is termed: A. minification gain B. conversion ratio C. modulation transfer ratio D. magnification technique

A. minification gain

Automatic brightness control during fluoroscopy adjusts the: A. peak kilo voltage (kVp) and milliamperage (mA) B. backup timer C. mill amperage (mA) and time D. peak kilo voltage (kVp) and time

A. peak kilo voltage (kVp) and milliamperage (mA)

The area of unsharpness around a radiographic detail is termed: A. penumbra B. umbra C. remnant D. fluorescence

A. penumbra

Human vision under daylight conditions is controlled by the cones of the retina and is commonly referred to as: A. photopic vision B. scotopic vision C. mesonic vision D. chromatic vision

A. photopic

Improper angulation of the tube-to-part-to-image receptor alignment results in: A. shape distortion B. minification C. Nyquist distortion D. umbra

A. shape distortion

A 15% decrease in kilovoltage peak accompanied by a 50% increase in milliampere-seconds will result in a: A. shorter scale of contrast B. increase in exposure latitude C. increase in density D. decrease in recorded detail

A. shorter scale of contrast

A beam-splitting mirror is required in the fluoroscopic imaging chain to allow for: A. static image recording B. image magnification C. automatic brightness control D. image minification

A. static image recording

The reduction of the brightness at the periphery of an image intensified is termed: A. vignetting B. diminution C. lateral dispersion D. modulation transfer

A. vignetting

A technique of 150 mA, 0.030 sec. and 100 kVp could be changed to 300 mA, _________ and 85 kVp with no appreciable change in optical density. A. 0.015 sec B. 0.030 sec C. 0.045 sec D. 0.060 sec

B. 0.030 sec

The photographic properties of radiographic image quality include: 1. contrast 2. density 3. distortion A. 3 only B. 1 and 2 only C. 1 and 3 only D. 2 and 3 only

B. 1 and 2 only

Which of the following will serve t reduce the production of scatter radiation: 1. increased collimation 2. the use of a cone for beam restriction 3. an air-gap technique A. 3 only B. 1 and 2 only C. 2 and 3 only D. 1, 2 , and 3

B. 1 and 2 only

What is the actual size of a heart whose image is 10.2 cm wide on a PA chest radiograph produced at 180 cm when the heart is located 4 cm from the film? A. 1.02 cm B. 10.0 cm C. 14.2 cm D. 20.4 cm

B. 10.0 cm

Which of the following directly affect the spatial resolution of a digital radiographic system? 1. tube potential (kVp) 2. matrix size 3. sampling frequency 4. pixel dimension 5. DEL size A. 1, 2 and 4 B. 2, 3, 4 and 5 C. 1, 4 and 5 D. All (1-5)

B. 2, 3, 4 and 5

How much of an adjustment in mAs must be made to order to see (notice) a change in radiographic density? A. 15% B. 30% C. 50% D. 100%

B. 30%

Decrease field size from 14x17 to 8x10 inches will result in: A. IR exposure/density increased B. IR exposure/density decreased C. No visible change in IR exposure/density

B. IR exposure/density decreased

Which of the following factors has the GREATEST effect on the recored detail of the radiographic image? A. SID B. OID C. focal spot size D. all of the above

B. OID

Assuming all other factors are to remain constant, radiographic exposure will INCREASE by varying: A. milliampere-seconds from 25 to 12 B. SID from 40 to 36 inches C. focal spot size from large to small D. kilovolts from 92 to 80

B. SID from 40 to 36 inches

If the radiographer is unable to achieve a short OID because of the structure of the body part or the patient condition, which of the following adjustments can be made to minimize penumbra? A. a larger spor size (FSS) should be used B. a longer source-to-image receptor distance (SID) should be used C. faster intensifying screens should be used D. a lower grid ratio should be used

B. a longer source-to-image receptor distance (SID) should be used

The time it takes for the human eye to adjust to the low light levels of conventional fluoroscopy is called: A. flicker time B. adaptation time C. integration time D. interlace time

B. adaptation time

The differences in adjacent densities across a radiograph may be referred to as: A. density B. contrast C. recorded detail D. scatter

B. contrast

Change from a 12:1 grid to a 5:1 grid will cause: A. contrast increased B. contrast decreased C. no visible change in contrast

B. contrast decreased

Increase from 60 to 78 kVp: A. contrast increased B. contrast decreased C. no visible change in contrast

B. contrast decreased

An exposure was made using 400 mA, 0.20 seconds, and 80 kVp at an SID of 72 inches. Each of the following changes will reduce IR exposure/density o 1/4 (25%) of the original, EXCEPT: A. change to 0.05 second exposure B. decrease SID to 36 inches C. add an 8:1 grid D. change to 57 kVp

B. decrease SID to 36 inches

As compared to historical direct view fluoroscopes, a substantial increase in image brightness is accomplished in modern RF systems using a/an: A. mirror system B. image intensification tube C. video tape unit D. magnification technique

B. image intensification tube

When involuntary motion must be reduced, the exposure time may be cut in half if the kVp is: A. doubled B. increased by 15% C. increased by 25% D. increased by 35%

B. increased by 15%

A change of 200 mA, 1/4 sec, and 65 kV to 200 mA, 1/8 sec, and 75 kV results in: A. greater IR exposure B. longer scale contrast C. reduced IR exposure D. shorter scale contrast

B. longer scale contrast

Which of the following theories dictates that IR exposure/density is based solely on energy deposited on the film, regardless of mA station and time combinations? A. inverse square law B. reciprocity law C. 30% rule D. 15% rule

B. reciprocity law

If the SID is HALVED, how could the mAs be adjusted to maintain the same IR exposure? A. cut in half B. reduced by a factor of 4 C. doubled D. increased by a factor of 4

B. reduced by a factor of 4

The principal method of limiting involuntary motion on a radiograph is the use of: A. sandbags B. short exposure times C. tape D. proper communication

B. short exposure times

If the distance between the object being radiographed and the image receptor is small, penumbra will be: A. large B. small C. magnified by a factor of 4 D. the same on both the anode and the cathode sides of the tube

B. small

As grid ratio is increased, A. the scale of contrast becomes longer B. the scale of contrast becomes shorter C. radiographic density increases D. radiographic distorsion decreases

B. the scale of contrast becomes shorter

Which of the following is the most important factor in controlling shape distortion? A. focal spot size B. tube/part angulation C. SID D. exposure time

B. tube/part angulation

The output screen in an image intensifier serves to convert the electronic image into: A. electron stream B. visible light image C. video signal D. television fram

B. visible light image

The total brightness gain of an image intensifier is a result of: 1. flux gain 2. minification gain 3. focusing gain A. 1 only B. 2 only C. 1 and 2 only D. 1 and 3 only

C. 1 and 2 only

Which of the following pathologic conditions would require a reduction in beam intensity to maintain appropriate IR exposure/density? 1. emphysema 2. osteoporosis 3. ascites A. 1 only B. 3 only C. 1 and 2 only D. 1, 2 and 3

C. 1 and 2 only

Acceptable methods of minimizing motion unsharpness include: 1. suspended respiration 2. long exposure time 3. velcro immobilization straps A. 1 only B. 1 and 2 only C. 1 and 3 only D. 1, 2 and 3

C. 1 and 3 only

Assuming no other compensatory change is made by the technologist, which of the following change(s) would have a NOTICEABLE effect on IR exposure/density? 1. Changing the kV from 86 to 100 2. changing the focal spot from small to large 3. changing the mAs from 100 to 110 4. changing from a table-top to a 12:1 grid 5. changing SID from 100 cm to 180 cm A. 1, 2 and 3 B. 1, 3 and 4 C. 1, 4 and 5 D. all of the above

C. 1, 4 and 5

An object to be radiographed measures 11.5 cm across it widest margins. If the radiographic image of this object measures 13.8 cm, what is the magnification factor? A. 0.833 B. 1.756 C. 1.2 D. 158.7

C. 1.2

A satisfactory radiograph was produced at an SID of 40 inches using 400 mA, 0.10 seconds, and 80 kVp. If the distance were changed to 72 inches, what new mAs would be required to maintain exposure to the IR? A. 12 mAs B. 70 mAs C. 130 mAs D. 160 mAs

C. 130 mAs mAs1/mAs2 = d1^2/d2^2

The image (visible light) on the input phosphor of the image intensifier tube is: 1. brighter than the output phosphor 2. dimmer than the output phosphor 3. larger than the output phosphor A. 1 only B. 2 only C. 2 and 3 only D. 1 and 3 only

C. 2 and 3 only

Which input screen mode of a triple field image intensifier will have the highest minification gain? (all other factors remaining the same) A. 10 cm B. 15 cm C. 23 cm D. all are the same

C. 23 cm

What will the magnification factor be for an object placed 20" from the x-ray tube source and 20" from the image receptor? A. 1x B. 1.5x C. 2x D. 4x

C. 2x

A satisfactory radiograph was made at 36 inches SID using 300 mA, 1/15 second, and 80 kVp. If the distance is changed to 48 inches, what new mAs would be required? A. 11 mAs B. 15 mAs C. 35 mAs D. 60 mAs

C. 35 mAs

A change in which geometric factor will NOT visibly affect the magnification of a radiographic image? A. SID B. SOD C. FSS D. OID

C. FSS

Change from a 100 small focal spot to a 100 large focal spot will result in: A. IR exposure/density increased B. IR exposure/density decreased C. No visible change in IR exposure/density

C. No visible change

Decrease from 75 mAs to 70 mAs will result in: A. IR exposure/density increased B. IR exposure/density decreased C. No visible change in IR exposure/density

C. No visible change

Which of the following will produce the GREATEST amount of size distortion? OID SID mAs A. 4" 40" 25 B. 4" 36" 20 C. 6" 36" 20 D. 6" 40" 25

C. OID: 6" SID: 36" mAs: 20

As a general rule, in the utilization of the anode heel effect the thickest portion of the body is placed under the: A. central ray B. Bucky side of the table C. cathode side of the tube D. anode side of the tube

C. cathode side of the tube

The ability of an imaging system to visualize an object with only a slight difference in density compared t the surrounding tissue is termed: A. quantum mottle B. spatial resolution C. contrast resolution D. visibility

C. contrast resolution

The relationship between the intensity of the incident light falling on one side of a processed film and the intensity of the light transmitted through the film is a measure of radiographic: A. contrast B. latitude C. density D. resolution

C. density

The principle advantage of image intensified fluoroscopy as compared to conventional projection radiography is that it allows for: A. higher resolution B. reduced patient dose C. dynamic viewing D. static imaging

C. dynamic viewing

Assuming all factors remain constant, according to the inverse square law what is the relationship of radiographic exposure to changes in SID? A. inversely proportional B. directly proportional C. inversely proportional to the square of the SID change D. directly proportional to the square of the SID change

C. inversely proportional to the square of the SID change

The primary exposure factor that is used for regulating radiographic contrast is: A. distance B. focal spot size C. kVp D. mAs

C. kVp

A properly exposed AP radiograph of the hip is produced using 74 kVp, 100 mA at 0.40 seconds. Due to uncontrollable patient motion, the image suffers from a lack of recorded detail. While maintaining radiographic exposure to the IR, which of the following should be used to reduce motion on the repeated image? kVp mA time(sec) A. 74 500 0.01 B. 74 300 0.20 C. 74 400 0.10 D. 74 200 0.02

C. kVp: 74 mA: 400 time(sec): 0.10

When the edge-enhancement function of a digital radiographic system is applied, __________ is/are filtered out of (removed from) the image. A. noise B. aliasing artifacts C. low-frequency signal D. high-frequency signal

C. low-frequency signal

The major factors affecting the amount of brightness gain in an image intensifier are: A. focal and scotopic vision gains B. adaption and vignetting gains C. magnification and flux gain D. dispersion and retinal gains

C. magnification and flux gain

Change from a 100 small focal spot to a 100 large focal spot will cause: A. contrast increased B. contrast decreased C. no visible change in contrast

C. no visible change in contrast

Decrease from 75 mAs to 70 mAs: A. contrast increased B. contrast decreased C. no visible change in contrast

C. no visible change in contrast

An UNDISTORTED radiographic image will result when the long axis of an object and the IMAGE RECEPTOR are: A. angled in relation to each other B. at right angles C. parallel D. perpendicular

C. parallel

With all other factors remaining constant, which of the following is MOST affected by selecting the large focal spot over the small for a given radiographic exposure? A. density B. contrast C. recorded detail D. patient dose

C. recorded detail

A radiograph with a small number of widely varying density values is said to possess: A. low subject contrast B. low inherent contrast C. short scale contrast D. long scale contrast

C. short scale contrast

What energy conversion occurs at the photocathode of an image intensification tube? A. x-ray energy is converted into visible light B. x-ray energy is converted into electron energy C. visible light is converted to electron energy D. electron energy is converted to visible light

C. visible light is converted to electron energy

If no other technical adjustments are made, which of the following would result in an increase in exposure to the CR plate? 1. increasing mAs 2. increasing kVp 3. decreasing SID A. 3 only B. 1 and 2 only C. 1 and 3 only D. 1, 2, and 3

D. 1, 2 and 3

If the radiographer makes no other changes to compensate, an increase in collimation will result in a: 1. decrease in IR exposure 2. decrease in scatter production 3. increase in contrast A. 2 only B. 1 and 2 only C. 2 and 3 only D. 1, 2, and 3

D. 1, 2 and 3

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 a high kVp A. 1 only B. 1 and 2 only C. 1 and 3 only D. 1, 2 and 3

D. 1, 2 and 3

The total brightness of fluoroscopic image can be increased by increasing the: 1. radiation exposure to the patient and input screen 2. minification gain 3. flux gain 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 directly affect shape distortion? 1. alignment of tube to the part 2. alignment of tube to the image receptor 3. alignment of part to the image receptor 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 may affect IR exposure/density? 1. average atomic number of anatomic structures 2. pathologic conditions 3. tissue thickness (size) A. 1 only B. 3 only C. 1 and 3 only D. 1, 2 and 3

D. 1, 2 and 3

If the radiographer makes no other changes to compensate, and increase in collimation will result in a: 1. decrease in IR exposure 2. decrease in scatter production 3. increase in contrast A. 2 only B. 1 and 2 only C. 2 and 3 only D. 1, 2 and 3

D. 1,2 and 3

A radiographic image is produced by using 20 mAs and 100 kVp. Which combination of technical factors would maintain the original IR exposure but provide an image with LOWER radiographic contrast? A. 40 mAs, 85 kVp B. 10 mAs, 100 kVp C. 20 mAs, 115 kVp D. 10 mAs, 115 kVp

D. 10 mAs, 115 kVp

What is the total brightness fain of a fluoroscopic image if an image intensification tube has an inout phosphor diameter of 20 cm, and output phosphor diameter of 5 cm, and flux gain of 80? A. 5x B. 160x C. 320x D. 1280x

D. 1280x

In comparison with 60 kVp, 80 kVp will: 1. produce less scatter radiation 2. produce longer scale contrast 3. produce more scatter radiation A. 1 only B. 3 only C. 1 and 2 only D. 2 and 3 only

D. 2 and 3 only

If the intensity of a particular x-ray bean is 80 mR at 180 cm, what would its intensity be at 100 cm? A. 25 mR B. 44 mR C. 144 mR D. 260 mR

D. 260 mR I1/I2 = d2^2/d1^2

A lateral radiograph of the c-spine was produced at 100 cm using 100 mA and 0.1 second exposure. If it is desired to increase the distance to 200 cm, what should the new milliampere (mA) setting, all other factors remaining the same? A. 100 B. 200 C. 300 D. 400

D. 400

Which of the following combinations will produce the LEAST amount of unsharpness? FSS OID SID A. 2.0 mm 6" 40" B. 1.0 mm 4" 40" C. 0.6 mm 3" 40" D. 0.3 mm 2" 40"

D. FSS: 2.0 mm OID: 2" SID: 40"

During digital imaging the smallest sized object (maximum spatial frequency) that may be imaged is referred to as the: A. Pendergast frequency B. Gurney-Mott frequency C. Quantum Mottle frequency D. Nyquist frequency

D. Nyquist frequency

An exposure was made using 200 mA, 0.05 seconds, and 75 kVp. Each of the following changes would double exposure to the image receptor EXCEPT: A. change to 0.1 second exposure B. change to 86 kVp C. change to 20 mAs D. change to 100 mA

D. change to 100 mA

If a technologist were to keep all technical factors constant, adding a grid would have which of the following effects on radiographic quality? A. increase in density and contrast B. decrease in density and contrast C. increase in density and decrease in contrast D. decrease in density and increase in contrast

D. decrease in density and increase in contrast

In a fluoroscopic image-intensification tube, the path of electron flow from the photocathode to the output phosphor is controlled by the: A. focusing cup B. photocathode C. output phosphor D. electrostatic lenses

D. electrostatic lenses

All of the following have an impact on radiograph contrast EXCEPT? A. photon energy B. grid ratio C. OID D. focal-spot size

D. focal spot size

The primary exposure factor that is used for controlling IR exposure/density is: A. distance B. focal spot size C. kVp D. mAs

D. mAs

Long scale contrast would be most correctly defined as: A. increased difference between adjacent densities B. narrow latitude C. high contrast D. many shades of gray

D. many shades of gray

The geometric distortion of the fluoroscopic image due to the curved input screen is called: A. vignetting B. diminution C. lateral dispersion D. pin cushion effect

D. pin cushion effect

Which of the following directly controls the brightness of the densities displayed on a digital radiograph? A. matrix size B. exposure index C. window width D. window level

D. window level

Most modern image intensifiers utilize an output fluorescent screen layer which is composed of: A. calcium tungstate B. cesium iodide C. barium lead sulfate D. zinc cadmium sulfide

D. zinc cadmium sulfide

Which of the following changes is likely to have the MOST NOTICEABLE effect on radiographic contrast? A. changing the kV from 86 to 82 B. changing the focal spot from small to large C. changing the mAs from 100 to 125 D. changing from table-top (non-grid) to a 12:1 grid

D.changing from table-top (non-grid) to a 12:1 grid

A device designed to electronically amplify the brightness of the fluoroscopic image:

Image intensifier

The enlargement of a radiographic image as compared to the actual size of the object:

Magnification

The value calculated by dividing the SID by the SOD

Magnification factor

Human vision under low-light conditions as controlled by the rods of the retina:

Scotopic vision

The ability of an imaging system to display fine details separately:

Spatial resolution

This type of radiographic contrast may be negatively affected by pathologic conditions:

Subject contrast

He invented the fluoroscope in 1896:

Thomas edison

This QC testing precess ensures that an x-ray tube accurately repeats an exposure for a given technique:

exposure reproducibility


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