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