Seminar- Digital Imaging Questions

in electronic imaging, as digital image matrix size increases: 1. pixel size decreases 2. resolution decreases 3. pixel depth decreases a.1 only b. 2 only c. 1, 2 d. 2,3

a. 1 only ( pixel size decreases)

the direct conversion (one step) system has the x-ray interact directly with a layer of: a. amorphous selenium b. cesium iodide c. silicon

a. amorphous selenium

edge enhancement provides: a. artificial increase in display contrast at an edge of the image. b. artificial increase in display density at an edge of the image. c. artificial increase in recorded detail at an edge of the image d. artificial increase in spatial resolution at an edge of the image.

a. artificial increase in display contrast at an edge of the image.

the indirect conversion process in D.R. involves a layer of _____ which produces a flash of light. a. cesium iodide b. selenium c. zinc cadmium sulfide

a. cesium iodide

a _______ relationship exists between window level and brightness. a. direct b. indirect

a. direct

The main difference between direct capture and indirect capture DR is that a. direct capture/ conversion has no scintillator b. direct capture/conversion uses a photostimulable phosphor c. in direct capture/ conversion , light is detected by CCD's d. in direct capture/conversion,light is detected

a. direct capture/ conversion has no scintillator

the visible image may also be called the: a. manifest image b. image-in-waiting c. preprocessed image d. latent image

a. manifest image

The smallest component of a matrix image that represents an xray intensity is called a(n) A. pixel. B. histogram. C. algorithm. D. brightness.

a. pixel

when working with CR and DR, one must be aware that their response to scatter radiation is: a. very sensitive b. minimally sensitive c. irrelevant

a. very sensitive

which of the following is/are true when comparing film screen imaging to CR imaging? a. CR DQE is better than film screen b. CR has a wider exposure range than film screen c. CR has better spatial resolution than film screen a. 1 b. 1, 2 c. 2,3 d. 1,2,3,

b. 1 & 2 -CR DQE is better than F.S. -CR has a wider exposure range than F.S.

an alogrithm is: a. a mathematical hypothesis used in imaging. b. a mathematical formula used to reconstruct the image in digital imaging. c. an advanced imaging procedure d. the mathematical basis for film-screen imagin

b. a mathematical formula used to reconstruct the image in digital imaging.

The mathematical formula used to construct a digital image is called a(n) A. histogram. B. algorithm. C. postprocessing enhancement. D. matrix.

b. alogrithm

increasing the window level will increase the image _________. a. contrast b. brightness c. spatial resolution d. contrast resolution

b. brightness.

the term windowing describes the practice of: a. varying the automatic brightness control b. changing the image brightness and/or contrast scale c. varying the FOV d. increasing resolution

b. changing the image brightness and/or contrast scale

image brightness in computed radiography may be adjusted by: a. doubling the kvp b. changing the window level c. repeating the exposure d. using digital fluoroscopy

b. changing the window level

Increasing the pixel depth will improve: a. spatial resolution b. contrast resolution c. density d. brightness

b. contrast resolution

A disadvantage of flat panel direct capture detectors is A. increased patient dose. B. difficulty in mobile imaging. C. increases time to view image. D. narrow dynamic range.

b. difficulty in mobile imaging

the range of exposure intensities an IR can accurately detect determines its: a. matrix b. dynamic range c. pixel bit depth d. histogram

b. dynamic range

What occurs when the exit radiation interacts with a photostimulable imaging plate? A. Fluorescence B. Energy absorption C. Phosphorescence D. Photoemission

b. energy absorption

Smoothing provides: a. Higher spatial resolution b. Equalization c. Evenness in brightness d. Higher contrast resolution

b. equalization

computed radiography IP are coated with: a. cesium iodide b. europium activated barium fluorohalide c. selenium d. silicon

b. europium activated barium fluorohalide

CR cassettes should be erased: a. every 24 hours b. every 48 hours c. every 3 months d. weekly

b. every 48 hours

A function that allows selection of preset terms or text input on images is called: a. image stitching b. image annotation c. image orientation d. shuttering

b. image annotation

the images on radiologists monitors appear: a. the same as on radiographers monitors. b. in greater detail than on radiographers monitors. c. in less detail than on radiographers monitors

b. in greater detail than on radiographers monitors.

a digital image is composed of rows and columns known as a: a. photonic image b. matrix c. digital d. cyborg assimilator

b. matrix

What feature is used to display RIS information on current patients? a. HIS b. modality work list c. PACS d. DICOM

b. modality work list

film screen has a _______ dynamic range, and digital imaging has a _______ dynamic range. a. narrow: narrow b. narrow: wide c. wide: narrow d. wide: wide

b. narrow: wide

what is a limitation of conventional radiography? a. poor resolution b. poor soft tissue differentiation c. increased quantum mottle d. transporting cassettes

b. poor soft tissue differentiation

comparing screen film with CR workload (time required to do the exam) does NOT include: a. expose cassette b. reload the cassette c. position patient d. select kVp

b. reload the cassette

digital image view is called a ________. a. hard copy b. soft copy

b. soft copy

Increasing the number of pixels in the image matrix will increase: a. contrast resolution b. spatial resolution c. brightness d. density

b. spatial resolution

the letters TFT stand for: a. to formulate text translation b. thin film transistor c. test scheduled for tomorrow d. thin film text

b. thin film transistor

Consistency of image appearance is achieved through the use of: a. Higher speed class b. Uniform processing codes c. More effective postprocessing d. Lower exposure index numbers

b. uniform processing codes

if the exposure field is not accurately recognized, the histogram: a. narrows b. widens c. remains the same. d. none of the above

b. widens

image brightness on a display monitor is adjusted by: a. scanning lines b. window level c. window width d. matrix size

b. window level

radiographic contrast in computed radiography may be adjusted by changing the: a. window level b. window width c. area of the patient being irradiated d. imaging plate

b. window width

resolution in CR increases as: 1. laser beam size decreases 2. monitor matrix size decreases 3. psp crystal size decreases a. 1 only b. 1,2 c. 1,3 d. 1,2,3

c. 1,3 laser beam size decreases psp crystal size decreases

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

c. 2,3 (pixel size decreases and spatial resolution increases)

the luminescent light emitted by the PSP is transformed into the image seen on the CRT by the : a. psp b. scanner reader c. adc d. helium neon laser

c. ADC

In digital fluoroscopy and computed radiography, the energy must be changed to digital by a(n): a. digital-to-analog converter b. flux capacitor c. analog to digital converter d. dvd-rom

c. analog to digital converter

ncreasing the window width of a digital image on a display monitor A. decreases the brightness. B. increases the brightness. C. decreases the contrast. D. increases the contrast.

c. decreases the contrast

a histogram analysis error may be caused by: a. excessive mAs b. Pixel unresponsiveness c. inappropriate collimation d. excessive kVp

c. inappropriate collimation

Image noise can be decreased by A. decreasing xray dose. B. increasing edge enhancement. C. increasing xray dose. D. decreasing window level.

c. increasing x-ray dose (mottle)

the window level in computed radiography is the: a. area of the patient being irradiated b. amount of radiation needed to obtain the image c. midpoint of densities d. toe of the H&D curve

c. midpoint of densities

the component of a CR image plate that records the radiologic image is the: a. emulsion b. helium neon laser c. photostimulable phosphor d. scanner reader

c. photostimulable phosphor (made of barium fluorohalide)

In digital imaging, TFT/ DEL size is related to : a. contrast b. brightness c. spatial resolution d. plate size

c. spatial resolution

in computer radiography, each pixel corresponds to a shade of gray representing an area in the patient known as a(n): a. pathology b. density c. voxel d. artifact

c. voxel

Radiographic contrast on a display monitor is adjusted by: a. scanning lines b. window level c. window width d. matrix size

c. window width

The differences between CR and DR include: 1. CR uses IP's 2. CR has higher DQE and lower patient dose 3. CR images are displayed immediately a. 1 b. 1,2 c. 2,3 d. 1,2,3

d. 1, 2, 3 1. CR uses IP's 2. CR has higher DQE and lower patient dose 3. CR images are displayed immediately

characteristics of DR imaging include: 1. solid state receptor plates 2. a direct capture imaging system 3. immediate image display a.1 only b. 1, 3 c. 2,3 d. 1,2,3

d. 1,2,3 1. solid state receptor plates 2. a direct capture imaging system 3. immediate image display

Brightness and contrast resolution in digital imaging can be influence by: 1. window level 2. window width 3. look up table a. 1 b.1,2 c. 2,3 d. 1,2,3

d. 1,2,3 1. window level 2. window width 3. look up table

For the same FOV,as the matrix size increases 1. spatial resolution increases 2. image quality increases 3. pixel size decreases a.1 b. 1,2 c. 2,3 d.1,2,3 (all the above)

d. 1,2,3 (all the above)

Digital radiography includes image acquisition methods that include A. computed radiography. B. flat panel direct capture detectors. C. chargedcoupled devices. D. all of the above.

d. all the above

The term voxel is associated with all of the following except: a. bit depth b. volume element c. measured in Z direction d. field of view

d. field of view

The term pixel is associated with all of the following except: a. two dimensional b. picture element c. measured in x y direction d. how much of the part is included in the matrix

d. how much of the part is included in the matrix

Energy in a CR imaging plate is released after exposure to : a. developer solution b. white light c. ultrasound d. laser beam

d. laser beam

In order to change the visibility of a digital image, lookup tables (LUT) alter the A. matrix size. B. histogram. C. pixel size. D. pixel value.

d. pixel value

A geometric characteristic of a computerized image is known as A. sharpness. B. noise. C. mottle. D. spatial resolution.

d. spatial resolution

Computed radiography has the advantage of A. less expensive equipment. B. improved resolution. C. latent image formation. D. wide dynamic range.

d. wide dynamic range