Principles of Imaging questions

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The emission of light when stimulated by a high intensity laser beam is: a. Luminescence b. Photostimulable phosphor c. Photostimulable luminescence d. None of the above

*Photostimulable luminescence*

DR imaging systems briefly store the electrical charge in the: a. ADC b. TFT ((thin-film transistor) c. CRT d. EST

*TFT* ((thin-film transistor)

The DR detector array is typically located: a. Inside the cassette b. By the computer keyboard c. On top of the table d. Where you would normally find the Bucky tray

*Where you would normally find the Bucky tray*

More

12. When operated in magnification mode, the electrostatic lenses have ________ of a negative charge. a.Less b.More c.The same amount as usual d.One half

Density control

12. When using AEC with film-screen, what should the radiographer adjust to manipulate the overall density of the image? a.kVp b.Backup time c.Focal spot size d.Density control

No change in; decreased

12. When using a digital imaging system, changing from 8 × 10 collimation to 14 × 17 collimation would result in _____________ brightness and ____________ contrast. a.No change in; no change in b.Decreased; increased c.No change in; decreased d.Decreased; decreased

The beam splitting mirror can only be used with _____ ______ because the fiber optics won't allow the mirror to be introduced

optical lenses

The technique chart cannot provide information for all patient variables. It is up to the radiographer to

use critical thinking skills to assess the patient and make adjustments

Because accurate centering is critical to effective use of AEC, it is not a good idea to

use this technology when the location of the anatomy of interest is uncertain

AEC devices are unable to determine the type of the image receptor that's being used. If the wrong IR type is used by mistake, the resulting image

will have inappropriate exposure to the IR

Newer x-ray units may keep you from making an exposure if

you've selected the table Bucky on the control panel but there's no IR in the table Bucky

2. Increased CR angulation 3. Decreased SID

1. A digital image with increased distortion may be due to: 1. Decreased OID 2. Increased CR angulation 3. Decreased SID a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

To reduce repeats and improve image quality

1. Why was automatic exposure control (AEC) originally developed? a. To decrease the need for technique charts b. To make the radiographer more of a "button pusher" c. To reduce repeats and improve image quality d. To increase productivity and patient dose

Dynamic

1. ___________ imaging is accomplished with fluoroscopy as opposed to radiography. a.Static b.Still c.Dynamic d.Colorized

Exposure time

10. AEC eliminates the need for the radiographer to select the actual _____ the examination will require. a.kVp b.SID c.Exposure time d.Focal spot size

Newer; 1%

10. The conversion factor is a(n) ___________ term for brightness gain and is typically about __________ of the brightness gain value. a.Older; 1% b.Older; 10% c.Newer; 1% d.Newer; 10%

- No change in; no change in

10. When using a digital imaging system, changing from 70 to 85 kVp would result in _____________ brightness and ____________ spatial resolution. a- Increased; no change in b- Decreased; increased c- No change in; decreased d- No change in; no change in

ABC

11. In reference to image intensification, the function that adjusts and maintains the overall image brightness and contrast during the fluoroscopic procedure is: a.DQE b.APR c.ABC d.AEC

kVp

11. When using AEC, what should the radiographer adjust to manipulate the contrast of the image? a.kVp b.Detector selection c.Exposure time d.Focal spot size

No change in; no change in.

11. When using a digital imaging system, changing from 40" SID to 72" SID would result in _____________ brightness and ____________ contrast. a.No change in; no change in. b.Decreased; increased. c.No change in; decreased. d.Decreased; decreased.

MF = full size input phosphor / selected input phosphor

13. The formula to determine the amount of magnification created when in magnification mode is: a.MF = full size input phosphor / selected input phosphor b.MF = full size input phosphor2 / selected input phosphor2 c.MF = selected input phosphor / full size input phosphor d.MF = selected input phosphor2 / full size input phosphor2

150% of the expected mAs

13. What is the appropriate setting for backup time/mAs? a.50% of the expected mAs b.100% of the expected mAs c.150% of the expected mAs d.400% of the expected mAs

- No change in; decreased

13. When using a film-screen imaging system, changing from small to large focal spot size would result in _____________ density and ____________ spatial resolution. a- No change in; no change in b- Decreased; increased c- No change in; decreased d- Decreased; decreased

1.3 Based on the formula, the MF = the full size of the input phosphor (30 cm) / the selected input phosphor size (23 cm)

14. If a 30/23/15 cm image intensifier is operated in the 23 cm mode, the fluoroscopic image will be magnified by a factor of: a.1.3 b.1.5 c.1.7 d.2

To prevent excessive exposure of the patient

14. What is the purpose of setting a backup time/mAs? a.To prevent excessive exposure of the patient b.To make certain the contrast is acceptable if the chosen kVp is too low c.To make certain the density is acceptable if the patient moves d.To prevent the selection of the wrong detector

Decreased; increased

14. When using a film-screen imaging system, changing from 85 to 70 kVp would result in _____________ density and ____________ contrast. a.No change in; no change in b.Decreased; increased c.No change in; decreased d.Decreased; decreased

Spatial resolution

15. Magnification of the fluoroscopic image results in improved: a.Brightness b.Spatial resolution c.Contrast d.Exposure

Anatomically programmed radiography

15. What does APR stand for? a.All programming radiology b.Anatomically programmed radiography c.Accurately positioned radiographs d.None of the above

Increased; decreased

15. When using a film-screen imaging system, changing from a 200 to a 400 speed system would result in _____________ density and ____________ spatial resolution. a.No change in; no change in b.Decreased; increased c.No change in; decreased d.Increased; decreased

The patient receives additional dose.

16. A disadvantage of using magnification mode during fluoroscopy is: a.The image has less resolution. b.The image brightness is inconsistent. c.The patient receives additional dose. d.None of the above

Density will decrease

16. When doing a film-screen study using AEC, what will happen to the density in the area of interest when changing from 70 kVp to 90 kVp? a.Density will increase. b.Density will decrease. c.Density will not change.

Decreased; decreased

16. When using a film-screen imaging system, increasing the central angle would result in _____________ density and ____________ spatial resolution. a.No change in; no change in b.Decreased; decreased c.No change in; decreased d.Decreased; increased

8 mAs @ 80 kVp

17. A film-screen image produced using 16 mAs @ 80 kVp has to be repeated because it is too dark. Which of the following exposure factors would be the best choice to correct the problem? a.4 mAs @ 80 kVp b.8 mAs @ 80 kVp c.8 mAs @ 68 kVp d.16 mAs @ 68 kVp

4 to 6 Lp/mm

17. Typical fluoroscopic systems have spatial resolution capabilities in the range of: a.2 to 3 Lp/mm b.4 to 6 Lp/mm c.7 to 9 Lp/mm d.10 to 12 Lp/mm

density will increase

17. When doing a film-screen study using AEC, what will happen to the density in the area of interest when changing from −1 to +1 density setting? a.Density will increase. b.Density will decrease. c.Density will not change.

The curved shape of the photocathode

18. In fluoroscopy, shape distortion is caused by: a.Angling the tube b.Angling the image intensifier c.The curved shape of the photocathode d.The position of the electrostatic focusing lenses

Underexposed; doubled

18. Using a Konica digital imaging system, if an image's S number is 600 while the optimal range ends at 300, this means that the IR was ______________ and the exposure to the IR needs to be ___________________. a.Underexposed; doubled b.Under exposed; halved c.Overexposed; doubled d.Overexposed; halved

Brightness will not change.

18. When doing a CR study using AEC, what will happen to the brightness in the area of interest when changing from the −1 to +1 density setting? a.Brightness will increase. b.Brightness will decrease. c.Brightness will not change.

Pincushion appearance

19. Distortion of the fluoroscopic image that appears as unequal magnification is: a.Noise b.Pincushion appearance c.Vignetting d.Magnification

Overexposed; reduced by a factor of four

19. Using a Carestream digital imaging system, if an image's EI number is 1800 while the optimal range ends at 1200, this means that the IR was ______________ and the exposure to the IR needs to be ___________________. a.Underexposed; doubled b.Underexposed; increased by a factor of four c.Overexposed; halved d.Overexposed; reduced by a factor of four

Patient exposure will increase.

19. When doing a CR study using AEC, what will happen to the patient exposure when changing from the −1 to +1 density setting? a.Patient exposure will increase. b.Patient exposure will decrease. c.Patient exposure will not change.

Conversion factor

8. This is measured in cd/m2/mR/s. a.Brightness gain b.Flux c.Minification gain d.Conversion factor

1. Increased central ray angulation 3. Decreased SID

2. A digital image with decreased spatial resolution may be due to: 1. Increased central ray angulation 2. Decreased grid ratio 3. Decreased SID a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

X-rays to light to electrons to light

2. Which of the following most accurately shows the energy sequence during image-intensified fluoroscopy? a.Light to x-rays to electrons to light b.X-rays to light to electrons to light c.X-rays to electrons to light d.Electrons to light to electrons

mAs readout

2. Which of the following terms does not belong in the list? a. Photodiode b. Ion chamber c. Ionization chamber d. mAs readout

Vignetting

20. A loss of brightness around the edge of the fluoroscopic image due to the curve of the photocathode is: a.Noise b.Pincushion appearance c.Vignetting d.Magnification

Underexposed

20. If the detector is directly exposed to the primary beam during a film-screen study, the area of interest will appear: a.Overexposed b.Underexposed c.Correctly exposed d.To have high contrast

Underexposed; increased by a factor of two

20. Using an Agfa digital imaging system, if an image's exposure indicator is 2.3 lgM while the optimal range begins at 2.6 lgM, this means that the IR was ______________ and the exposure to the IR needs to be ___________________ . a.Underexposed; increased by 30% b.Underexposed; increased by a factor of two c.Overexposed; decreased by 30% d.Overexposed; decreased by a factor of two

mAs readout

21. In order to become familiar with manual technical factors (i.e., setting mAs and kVp and not using AEC), it is very helpful to pay attention to the: a.Exposure time b.Heat units c.Density control d.mAs readout

Noise

21. Increasing the mA is the way to correct a fluoroscopic image that has: a.Noise b.Pincushion appearance c.Vignetting d.Magnification

Brightness/density and image contrast

21. The visibility of anatomic structures in a radiographic image is determined by: a.Spatial resolution and image contrast b.Brightness/density and image contrast c.Spatial resolution and brightness/density d.All of the above

Using a TV monitor

22. The conventional or current method for viewing the fluoroscopic image is by: a.Using a hand-held device b.Looking directly at the output phosphor c.Using a TV monitor d.Using a mirror-optics system

2. Increasing mAs 3. Changing to a lower ratio grid

22. Which of the following would reduce quantum noise in a digital image? 1. Decreasing mAs 2. Increasing mAs 3. Changing to a lower ratio grid a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

1 ms

22. With modern x-ray equipment, the AEC system's minimum response time is typically: a.1 ms b.10 ms c.50 ms d.100 ms

1. Decreasing mAs 3. Imaging a thicker part

23. Assuming no other changes are made, which of the following would result in increased quantum noise in a digital image? 1. Decreasing mAs 2. Increasing kVp 3. Imaging a thicker part a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

Centering

23. The most common cause for repeating images done with film-screen and AEC is inaccurate: a.kVp selection b.Backup mAs selection c.Centering d.Alignment of the tube and image receptor

Camera tube

23. Vidicon refers to a type of: a.Television monitor b.Camera tube c.CCD d.Fiber optics

Reports the actual mAs used for an exposure

24. The mAs readout: a.Is of little value because it's not necessary to know mAs when using AEC b.Reports the actual mAs used for an exposure c.Reports the patient dose for the entire imaging study d.Allows the radiographer to better set the mAs for an AEC examination

Raster

24. When the electron beam in the camera travels back and forth across, from the top to bottom, it is moving in a ___________ pattern. a.Sweep b.Brush c.Raster d.Rooster

CCD

25. Semiconductor capacitors are components of the: a.Camera tube b.CCD c.Image intensifier d.X-ray tube

Be a good idea because the exposure time will decrease

25. With a CR system, when using AEC to image a patient who is having difficulty holding still, increasing the mA (if the unit allows) will: a.Be a bad idea because the patient will be overexposed b.Be a bad idea because the patient will be underexposed c.Be a good idea because the exposure time will increase d.Be a good idea because the exposure time will decrease

Pixel

26. Each capacitor in a CCD represents a(n): a.Line b.Image c.Pixel d.Electric charge

600 mAs

26. If the backup time/mAs is automatically set by the x-ray unit, the exposure should end when a maximum of _________ has been reached. a.600 s b.600 kVp c.600 mA d.600 mAs

Television monitor

27. The CCD's electrical charge from the capacitors is sent to the: a.Output phosphor b.Television monitor c.X-ray tube d.Image intensifier

Set manual technique

27. When doing a tabletop forearm study with CR, you should: a.Use AEC b.Set manual technique c.A and B d.None of the above

Link the output phosphor and camera or CCD

28. The fiberoptic bundle or optical lens system is used to: a.Deliver the image from the camera to the television monitor b.Record the fluoroscopic image c.Link the output phosphor and camera or CCD d.None of the above

Patient exposure is increased.

28. When a digital IR is overexposed due to poor use of AEC: a.Image contrast will be increased. b.Quantum noise may be highly visible. c.Patient exposure is increased. d.Patient exposure is unaffected.

Decrease

29. Exposure time will ______ using AEC when patient thickness decreases. a.Decrease b.Remain the same c.Increase d.Double

Allow spot filming to be done during fluoroscopy

29. The purpose of a beam splitting mirror is to: a.Be able to view the fluoroscopic image on more than one television b.Reduce the intensity of the image from the output phosphor c.Allow spot filming to be done during fluoroscopy d.None of the above

1. Decreased kVp 2. Increased grid ratio 3. Decreased patient thickness

3. A digital image with higher contrast may be due to: 1. Decreased kVp 2. Increased grid ratio 3. Decreased patient thickness a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

Output phosphor

3. The __________________ absorbs electrons and emits light. a.Input phosphor b.Output phosphor c.Photocathode d.Accelerating anode

Ionization chamber

3. Which automatic exposure device works by using a gas-filled chamber? a.Phototimer b.Diode sensor c.Ionization chamber d.Bucky proliferator

525 lines

30. Typical television monitors have: a.300 lines b.450 lines c.525 lines d.875 lines

Technique chart

30. Where does a radiographer find the established guidelines for selecting exposure factors for a radiographic examination? a.Technique chart b.Generator control panel c.Examination requisition d.B or C

1024 lines

31. A typical high resolution monitor will have: a.825 lines b.1024 lines c.1872 lines d.2034 lines

- To ensure consistent image quality - To reduce repeat imaging due to technique error and, in turn, reduce patient exposure

31. What is the purpose of a technique chart? a.To decrease patient exposure by always using the highest kVp required b.To ensure consistent image quality c.To reduce repeat imaging due to technique error and, in turn, reduce patient exposure d.B and C

Each radiographic tube

32. A technique chart should be established for: a.Each radiographer b.Each radiographic tube c.Each radiologist d.A and C

- Raster

32. The electron gun in the monitor moves in the same ___________ pattern as did the electron gun in the tube camera. a- Sweep b- Brush c- Raster d- Rooster

5 Lp/mm; 1 to 2 Lp/mm

33. The image intensifier is capable of resolving about ___________, while the monitor can resolve about _______________. a.1 to 2 Lp/mm; 1 to 2 Lp/mm b.1 to 2 Lp/mm; 5 Lp/mm c.5 Lp/mm; 5 Lp/mm d.5 Lp/mm; 1 to 2 Lp/mm

- The radiographic equipment must be operating properly. - A good quality control program is in place.

33. Which of the following is/are true regarding development of an effective technique chart? a.The radiographic equipment must be operating properly. b.A good quality control program is in place. c.The equipment must be from the same manufacturer. d.A and B

- Television monitor

34. In terms of resolution, the weakest part of the fluoroscopic system is the: a- Image intensifier b- Television monitor c- Camera tube d- None of the above

To measure the part

34. What are calipers used for? a.To measure the mA b.To select the kVp c.To select focal spot size d.To measure the part

OID

35. Which of the following is not part of a standardized technique chart? a.SID b.OID c.mA d.kVp

Cassette spot filming

35. Which of the following require the x-ray beam to be in radiographic mode? a.Cassette spot filming b.Film cameras for spot filming c.Videotape d.None of the above

Film cameras for spot filming

36. This recording system uses 70 mm or 105 mm film. a.Cassette spot filming b.Film cameras for spot filming c.Videotape d.None of the above

2 kVp -A 1 cm change in tissue thickness calls for a 2 kVp change when using a variable kVp-fixed mAs technique chart-

36. What is the appropriate change in kVp when using a variable kVp-fixed mAs technique chart for a 1 cm change in tissue thickness? a.2 kVp b.4 kVp c.6 kVp d.10 kVp

83 kVp - Increasing part thickness by 4 cm requires an increase of 8 kVp (2 kVp per centimeter)-

37. If a part measures 14 cm and requires the use of 75 kVp, how much kVp would a part measuring 18 cm require when using a variable kVp-fixed mAs technique chart? a.67 kVp b.77 kVp c.83 kVp d.91 kVp

- Cassette spot filming

37. This recording system allows the film to be divided into two, four, or more images. a- Cassette spot filming b- Film cameras for spot filming c- Videotape d- None of the above

Videotape

38. In order to record the dynamic image you will need to use: a.Cassette spot filming b.Film cameras for spot filming c.Videotape d.None of the above

A fixed kVp technique chart

38. What kind of chart uses a kVp value that is high enough to adequately penetrate the part but does not diminish radiographic contrast? a.A variable kVp technique chart b.A fixed kVp technique chart c.A fixed mAs technique chart d.A and C

- Film cameras for spot filming

39. The recording device that "photographs" the image off of the output phosphor is the: a- Cassette spot filming b- Film cameras for spot filming c- Videotape d- None of the above

It should be doubled.

39. When using a fixed kVp-variable mAs technique chart, if part thickness increases by 5 cm, what needs to happen to the mAs? a.It should be halved. b.It should be doubled. c.It should be quartered. d.It should be tripled.

1. Increased patient thickness 3. Increased kVp

4. A film-screen image with lower contrast may be due to: 1. Increased patient thickness 2. Increased beam restriction 3. Increased kVp a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

Input phosphor

4. The __________________________ absorbs x-rays and emits light. a.Input phosphor b.Output phosphor c.Photocathode d.Accelerating anode

In front of the image receptor

4. Where is the sensor located in an automatic exposure device with a gas-filled chamber? a.In front of the patient b.Behind the Bucky tray c.In front of the image receptor d.On the tabletop

Prior to the development of technique charts

40. Departmental standards, such as the SID or whether an examination is done tabletop or Bucky, should be determined: a.Prior to the development of technique charts b.After the development of technique charts c.At the same time as the development of technique charts d.Whenever the department can come to an agreement

An ADC

40. Early versions of digital fluoroscopy used the standard system and added: a.A different camera b.An ADC c.Videotape d.None of the above

Variable kVp-fixed mAs technique chart design

41. Accurate patient measurement is most critical for the: a.Variable kVp-fixed mAs technique chart design b.Variable kVp-variable mAs technique chart design c.Fixed kVp-variable mAs technique chart design d.Fixed kVp-fixed mAs technique chart design

- Makes the electrical signal understandable to the computer - Determines the contrast resolution of the system - Determines the image matrix

41. The analog to digital converter: a.Makes the electrical signal understandable to the computer b.Determines the contrast resolution of the system c.Determines the image matrix d.All of the above

A CCD

42. Digital fluoroscopy is improved by using: a.A vidicon camera b.Videotape c.A beam splitting mirror d.A CCD

Fixed kVp-variable mAs technique chart design

42. Radiographic contrast would be standardized with the: a.Variable kVp-fixed mAs technique chart design b.Variable kVp-variable mAs technique chart design c.Fixed kVp-variable mAs technique chart design d.Fixed kVp-fixed mAs technique chart design

Fixed kVp-variable mAs technique chart design

43. Generally speaking, patient dose will be decreased with the: a- Variable kVp-fixed mAs technique chart design b- Variable kVp-variable mAs technique chart design c- Fixed kVp-variable mAs technique chart design d- Fixed kVp-fixed mAs technique chart design

- CCD

43. Which of the following is more light-sensitive? a- Tube-type camera b- CCD c- There is no difference between the two.

Tube-type camera

44. Which of the following produces an image with more noise? a.Tube-type camera b.CCD c.There is no difference between the two.

80 mAs at 75 kVp

45. A patient measuring 26 cm requires 20 mAs at 75 kVp based on a fixed kVp-variable mAs technique chart. What technique should be used for the next patient, who measures 34 cm? a.40 mAs at 75 kVp b.80 mAs at 75 kVp c.20 mAs at 91 kVp d.40 mAs at 91 kVp

- Tube-type camera

45. Which of the following has more spatial distortion? a- Tube-type camera b- CCD c- There is no difference between the two.

Less; less

46. In comparison, the vidicon camera tube has ______________ spatial resolution, and the CCD requires ________________ radiation to produce a good fluoroscopic image. a.Less; more b.Less; less c.Better; more d.Better; less

The same mAs

46. Using the concept of comparative anatomy, if a child's elbow measures the same as an adult wrist and all other procedural variables are the same (i.e., SID, image receptor type, etc.), the child's elbow will require _____ in comparison to the adult wrist. a.Less mAs b.More mAs c.The same mAs d.Higher kVp

Visual cues for underexposure or overexposure are missing.

47. Exposure technique charts are possibly more important when using digital image receptors because: a.The equipment is more expensive. b.It's obvious when the wrong exposure factors have been used with digital IRs. c.Visual cues for underexposure or overexposure are missing. d.All of the above

CCD.

47. Use of which of the following systems will result in less radiation dose to the patient? a.Tube-type camera. b.CCD. c.There is no difference between the two.

In place of the image intensifier

48. The newest fluoroscopy systems use a flat-panel detector: a.To display the spot images during fluoroscopy b.To record the overhead images following fluoroscopy c.In place of the image intensifier d.In addition to the image intensifier

Higher

48. To take advantage of the fact that that digital image processing allows adjustment of the image contrast, optimal kVp for the fixed kVp-variable mAs technique chart for a digital room can be: a.Significantly lower b.Slightly lower c.The same d.Higher

a.Amorphous silicon indirect capture type c.Amorphous selenium direct capture type

49. Flat-panel detectors for fluoroscopic imaging can be the: a.Amorphous silicon indirect capture type b.Photostimulable phosphor plate type c.Amorphous selenium direct capture type d.A and C

The spine will have insufficient density.

49. When using film-screen, what happens when an outside detector is selected for an AP thoracic spine? a.The spine will have insufficient contrast. b.The spine will be too dark. c.The spine will have excessive contrast. d.The spine will have insufficient density.

2. Decreased SID 3. Increased film-screen speed

5. A film-screen image with increased density may be due to: 1. Increased OID 2. Decreased SID 3. Increased film-screen speed a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

Photocathode

5. This part of the image intensifier absorbs light and produces electrons. a.Input phosphor b.Output phosphor c.Photocathode d.Electrostatic focusing lenses

Phototimer

5. Which automatic exposure device works by converting x-ray photons first into light and then into an electronic signal? a.Phototimer b.Gas detector c.Ionization chamber d.Backup timer

Flat-panel detector in place of image intensifier

50. Which of the following is easier to move around and allows better access to the patient during a procedure? a.Conventional image intensifier b.Flat-panel detector in place of image intensifier c.There is no difference between the two.

Flat-panel detector in place of image intensifier.

51. Which of the following does not require any additional devices for spot filming during the fluoroscopic procedure? a.Conventional image intensifier. b.Flat-panel detector in place of image intensifier. c.There is no difference between the two.

- Flat-panel detector in place of image intensifier

52. Which of the following has a rectangular field of view and a wider dynamic range? a- Conventional image intensifier b- Flat-panel detector in place of image intensifier c- There is no difference between the two.

Conventional image intensifier b.

53. Which of the following has the possibility of demonstrating veiling glare and pincushion distortion? a.Conventional image intensifier b.Flat-panel detector in place of image intensifier c.There is no difference between the two.

Conventional image intensifier

54. Which of the following requires more radiation to produce quality fluoroscopic images? a.Conventional image intensifier b.Flat-panel detector in place of image intensifier c.There is no difference between the two.

6 months

55. Fluoroscopic equipment should be inspected every: a.Week b.Month c.6 months d.Year

Operational

56. The radiographer may be responsible for the ________________ inspection of the fluoroscopic equipment for QC purposes. a.Performance b.Operational c.A and B d.None of the above

Operational QC testing

57. Inspecting the protective curtain, Bucky slot cover, and fluoroscopic timer are part of the: a.Performance QC testing b.Operational QC testing c.A and B d.None of the above

Is smaller

58. As compared to the tube-type camera, the CCD: a.Is smaller b.Is larger c.Uses an electron gun to produce the video signal d.B and C

High; pulsed

59. The x-ray beam used with a digital fluoroscopic unit uses ___________ mA and a ______________ beam. a.Low; constant b.High; constant c.Low; pulsed d.High; pulsed

1. Increased SID 2. Decreased focal spot size 3. Decreased film-screen speed

6. A film-screen image with increased recorded detail may be due to: 1. Increased SID 2. Decreased focal spot size 3. Decreased film-screen speed a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

Larger

6. The input phosphor is ______________ than the output phosphor. a.Larger b.Smaller c.The same size as d.Brighter

Behind the image receptor

6. Where is the sensor located in an automatic exposure device that converts light into an electrical signal? a.In front of the patient b.Behind the image receptor c.In front of the image receptor d.On the tabletop

38 cm; 30 cm

60. The SSD should be no less than ___________ for a fixed or stationary fluoro unit and no less than ____________ for a mobile fluoro unit. a.38 cm; 30 cm b.30 cm; 38 cm c.38 inches; 30 inches d.30 inches; 38 inches

1. Decreased patient thickness 2. Increased SID

7. A film-screen image with decreased distortion may be due to: 1. Decreased patient thickness 2. Increased SID 3. Increased focal spot size a.1 & 2 only b.1 & 3 only c.2 & 3 only d.1, 2, & 3

Minification gain

7. The gain related to the decrease in size from the input to the output phosphor is the: a.Brightness gain b.Flux c.Minification gain d.Conversion factor

Seconds

7. Which exposure variable is controlled by the automatic exposure control device? a.kVp b.Focal spot size c.Seconds d.mA

Image density would be excessive

8. What would the result be if a film-screen radiographic examination required an exposure time shorter than the minimum response time of the AEC sensors? a.Image density would be optimal. b.Image density would be excessive. c.Response time has nothing to do with AEC. d.Image contrast would be high.

digital image brightness is independent of mAs, kVp, and patient thickness

8. Which of the following changes would produce a digital image with decreased brightness? a.Increased mAs b.Decreased kVp c.Increased patient thickness d.None of the above

Brightness gain = minification gain × flux gain

9. The formula for brightness gain is: a.Brightness gain = minification gain - flux gain b.Brightness gain = minification gain / flux gain c.Brightness gain = minification gain × flux gain d.None of the above

Minimum response time

9. What describes the shortest exposure time required for the AEC device to operate? a.Backup time b.Minimum response time c.Master density time d.A and C

No change in; no change in

9. When using a digital imaging system, changing from no grid to an 8:1 ratio grid would result in _____________ brightness and ____________ spatial resolution. a.Increased; no change in b.Decreased; increased c.No change in; decreased d.No change in; no change in

Pediatric patients

A variable kVp-fixed mAs chart may be most effective with: a.Geriatric patients b.Trauma patients c.Patients imaged with mobile equipment d.Pediatric patients

Ambient lighting refers to the darkness or brightness of the digital image viewing area

A very bright or high level of ambient lighting makes it more difficult to view the details of the digital image

The CR (computed radiography) phosphor layer is composed of: a. Gadolinium oxysulfide with terbium b. Barium fluorohalide with europium c. Lanthanum oxybromide with thulium d. Yttrium oxysulfide with terbium

Barium fluorohalide with europium

All of the data from the entire IP (including scatter outside the exposed field) may be included in the histogram analysis if: a. *Only one edge of the collimated field is identified*. b. Only three edges of the collimated field are identified. c. All four edges of the collimated field are identified. d. All of the above

Based on the histogram analysis, consistent image brightness is accomplished through: a. Adjustment of window width b. *Automatic rescaling* c. Manipulation of the exposure indicator d. Manipulation of the LUT

The distracting area of increased brightness surrounding a collimated image can be removed from the displayed digital image by: a. Masking b. Shuttering c. Electronic collimation d. *All of the above*

Decreasing the window level will result in an image with: a. Lower contrast b. Higher contrast c. *Decreased brightness* d. Increased brightness

The monitor matrix size should be _________________ the image matrix size. a. Smaller than b. *At least as large as* c. Five times larger than d. Ten times larger than

Diagnostic interpretation should be done at a ___________ display monitor. a. 1 megapixel b. 2 megapixel c. *5 megapixel* d. 15 megapixel

A high SNR (signal-to-noise ratio) means that the: a. *Signal strength is high*. b. Signal strength is low. c. Noise is high. d. B and C

Digital imaging processing refers to: a. *Computer manipulations applied to digital images* b. Creation of the digital latent image c. Chemical processing of the digital image d. None of the above

The dynamic range of a digital imaging system is significantly larger than a film-screen system

Digital imaging still requires sufficient exposure to produce a quality image. Too low of an exposure will result in an image with significant quantum noise

Windowing does not alter the original stored pixel values

Dry laser printers use heat to print the image and wet laser printers use liquid chemicals to produce a hard copy of the digital image

The CR (computed radiography) latent image consists of: a. Electrons trapped in the phosphor layer b. Clumps of metallic silver in the emulsion c. Light trapped in the phosphor layer d. The image as seen on the display monitor

Electrons trapped in the phosphor layer

Which of the following is not a component of the CR IP? a. Emulsion layer b. Support layer c. Phosphor layer d. Protective layer

Emulsion layer

With CR, when the x-ray photons are absorbed by the phosphor, the ___________ atoms become ionized. a. Barium fluorohalide b. Tungsten c. Europium d. Silver halide

Europium

With an FPD (flat-panel detector), electrical charges from each DEL are read out separately

Exit radiation is converted directly to an electrical signal with direct conversion detectors. Light is only involved with indirect conversion detectors

There is a small amount of light emission when x-rays first interact with the CR imaging plate phosphor. However, this is not part of image formation.

Exposed CR IPs should be processed within 1 hour after exposure to prevent latent image deterioration

The range of the histogram data set that should be included in the displayed image is determined by the: a. LUT b. EI c. *VOIs* (values of interest) d. LCD

In CR imaging, the ___________ of the imaging plate is scanned. a. Exposed portion b. Top half c. Bottom half d. *Entire area*

Using a 40 watt light bulb in a safelight will result in fog on the radiograph. The light bulb wattage is usually between 7.5 and 15

In order to maintain archival quality, radiographs must retain 10% to 15% moisture. Therefore, the dryer can remove no more than 90% of the film's moisture

_______ ________ is never a reason to adjust the density control. Correction of the centering problem is what's needed

Inaccurate centering

A CRT (cathode ray tube) type monitor: a. Has a fluorescent screen b. Uses an electron gun c. Scans in lines d. *All of the above*

LCD stands for: a. Liquid cathode display b. *Liquid crystal display* c. Logarithmically created digitization d. Layered components diagram

The computer system designed to distribute, store, and display digital images is: a. *PACS* (picture archival and communication system) b. HL7 c. DICOM d. RIS

Once the data is in digital format, there is no difference between image processing and display between CR and DR

The most important performance criterion of a film illuminator is: a. Its size b. *The uniformity of light intensity* c. The illuminator display matrix d. Having the brightest possible light

One and one half minutes (90 seconds) is a typical film processing cycle

The ability of the detector to accurately capture the variety of photon intensities in the remnant radiation is: a. Pixel depth b. *Dynamic range* c. ALARA d. Pixel sensitivity

Overexposing a digital image receptor may result in a quality image, but: a. Quantum noise will be visible. b. The SNR will be poor. c. *The ALARA principle has not been followed*. d. The system will not last as long as expected.

This material is composed of barium fluorohalide and makes up the primary component of the CR IP. a. Luminescence b. Photostimulable phosphor c. Photostimulable luminescence d. None of the above

Photostimulable phosphor

Digital images that include all the raw data appear: a. Very bright b. Very dark c. *With low contrast* d. With high contrast

Soft copy viewing means that the image is being viewed: a. *At a computer* b. On a soft piece of film c. In a soft light environment d. None of the above

_______ _______ are still needed when using AEC

Technique charts

_____ ______ can be slow in responding, seen as a brief delay in the brightness adjustment

The ABC

The pixel bit depth determines the image's: a. Brightness b. Contrast c. Spatial resolution d. *Contrast resolution*

The DICOM GSDF is used to evaluate the: a. *Display monitor* b. Film processor c. Histogram analysis d. Digital imaging system

Only DR combines image capture and readout. CR requires the image to go through a separate reader unit following image capture

The DR system does not require a separate reader unit

Which of the following exposure indicators has an inverse relationship with exposure to the IP? a. EI (Carestream) b. lgM (Agfa) c. *S number (Fuji)* d. All have an inverse relationship.

The _________ provides a method of altering the image to change the display of the digital image. a. Histogram b. *Lookup table* c. Exposure indicator d. Matrix

This postprocessing technique improves the visibility of small, high contrast structures. a. Smoothing b. Contrast enhancement c. *Edge enhancement* d. Subtraction

The communication standard for medical information is: a. PACS b. *HL7* (health level seven standard) c. DICOM d. RIS

Which of the following is not accomplished through the histogram analysis? a. Compensation for image underexposure b. Identification of the edges of the image c. *Manipulation of image contrast* d. Compensation for image overexposure

The histogram analysis represents the ______________ for different exposure levels. a. Intensity of exposure b. *Incidence of pixels* c. Exposure index d. All of the above

An image with high SNR (sound-to-noise ratio) will have increased detail visibility due to the minimal amount of quantum noise

The histogram for a digital image is compared to a pre-established histogram of the anatomic part being imaged

Using a lookup table to adjust the digital image's brightness changes the original pixel value

The monitors used for interpretation typically are larger and have higher resolution than other monitors in the department

Unfortunately, there is no standardization of exposure indicator values amongst the various vendors

The recommended ranges of exposure indicator values are different for extremity versus spine examinations

Increasing the window width will result in an image with: a. *Lower contrast* b. Higher contrast c. Decreased brightness d. Increased brightness

This postprocessing technique reduces the visibility of image noise. a. *Smoothing* b. Contrast enhancement c. Edge enhancement d. Subtraction

The numerical value indicating the level of radiation exposure to the digital IR is the: a. VOI b. Histogram c. *Exposure indicator* d. LUT

Which of the following changes in the exposure indicator values does NOT represent a doubling of radiation exposure to the IR? a. *S number (Fuji) changing from 200 to 400* b. S number (Fuji) changing from 400 to 200 c. EI (Carestream) changing from 1200 to 1500 d. EI (Carestream) changing from 1500 to 1800

The purpose of a camera tube or CCD is to

convert the output phosphor image to an electronic signal that can then travel to the television monitor for viewing

Optimal kVp levels have not been established. Each department needs to

determine the optimal kVp for each anatomic area

The _______ _______ in the television monitor sends out a constantly changing stream of electrons to activate the fluorescent screen, allowing display of various levels of brightness

electron gun

Even though the rooms seem identical, individual technique charts should be developed

for each tube

When a CCD is exposed to light, it

generates and briefly stores an electrical charge

Radiographers need to problem-solve when an image is overexposed. There are many variables that contribute to

image quality, and chart effectiveness is only one

The beam splitting mirror

is never used with fiber optics

The technical information displayed when using APR is a starting point. It is up to the radiographer to

make adjustments based on his or her knowledge and experience

In order to produce a radiographic image with structural lines as accurate as possible, you must

maximize the spatial resolution and minimize the distortion

In order for AEC to be used, the radiation must pass through the detectors. Because the AEC detectors cannot typically be moved to the tabletop, the radiographer must

set a manual technique for tabletop exams

Due to digital imaging systems' wider exposure latitude, part measurements can be less precise; patients can be categorized as

small, medium, or large

The need for increased exposure to the input phosphor when using magnification mode is automatically addressed by

the ABC

Each electron that interacts with the output phosphor will result in significantly more light photons being produced in comparison to

the number of light photons it took to release that electron

Routinely using plus or minus density settings indicates

there is a problem with the AEC system

When the radiographer is considering whether to repeat an image using AEC, it is important

to determine the reason the first radiograph failed


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