DVEP - DIGITAL FINAL EXAM QUESTIONS &
ANSWERS
CR acquire image how? - Answers :xray photons stimulate the electrons in the
phosphor layer (active layer)
What is needed to create an image using DR? - Answers :a flat panel detector and new
xray equipment
What is needed for indirect capture DR? - Answers :A scillintation phosphor converts
xray photons to light then a-si converts light to an electrical signal
CR storage phosphor? - Answers :Barium fluorohalide coated in europium
CR: What releases the stored phosphor plate energy? - Answers :a focused red laser
light
What is the function of LUT? - Answers :gives uniform contrast and brightness
Components of PACS? - Answers :reading stations, physician review stations, specialty
workstations, web access, archive sys., administrative stations
Digital image? - Answers :Recorded as multiple numeric values and divided into an
array of small elements
analog image? - Answers :refers to a device or system that captures or measures a
continuously changing signal
what is a pixel? - Answers :smallest element in a digital image
what is a matrix? - Answers :square arrangement of numbers and columns in a row
what is the relation between pixel and matrix? - Answers :Pixels make up the matrix
bit depth? - Answers :# of bits or pieces of info within each pixel
brightness? - Answers :appearance of an image on a display monitor
spatial resolution? - Answers :ability of the image system to demonstrate small details
contrast resolution - Answers :display subtle changes in shade of gray; directly related
to the bit depth
, Perfect system according to MTF? How does light affect it? - Answers :1 or 100%; ^
light = decrease in MTF
latitude? - Answers :range of exposure that can be used to create an image with
appropriate optical density
How does collimation affect the image in the CR processing? - Answers :
What is a histogram? how's it used? - Answers :graphical representation of exposure
values collected from the imaging plate
nyquist theorem? - Answers :Sampling Theorem: When sampling a signal, the sampling
frequency must be more than the bandwith
Wraparound image? - Answers :2 superimposed images slight out of alignment
resulting in moire effect
How soon should you process a CR plate? - Answers :Within an hour because the
image will start to fade
What is automatic rescaling? - Answers :exposure greater than or less than what is
needed to produce the image; produces uniformity
how does the algorithm affect the image? - Answers :
Too much manipulation will cause what? - Answers :
What does window (width) and (window) level control? - Answers :Ratio of black and
white (contrast);
brightness
What is shuttering? - Answers :Blacken out the white collimation borders
Image stitching? - Answers :used for anatomy or areas of interest too large for one
cassette
what is annotation? - Answers :information other than the standard identification
zoom? - Answers :allows magnification of entire image
function of the CR plate's active layer? - Answers :traps electrons during exposure
purpose of the barcode layer? - Answers :match the image information with the patient
identifying barcode on exam
ANSWERS
CR acquire image how? - Answers :xray photons stimulate the electrons in the
phosphor layer (active layer)
What is needed to create an image using DR? - Answers :a flat panel detector and new
xray equipment
What is needed for indirect capture DR? - Answers :A scillintation phosphor converts
xray photons to light then a-si converts light to an electrical signal
CR storage phosphor? - Answers :Barium fluorohalide coated in europium
CR: What releases the stored phosphor plate energy? - Answers :a focused red laser
light
What is the function of LUT? - Answers :gives uniform contrast and brightness
Components of PACS? - Answers :reading stations, physician review stations, specialty
workstations, web access, archive sys., administrative stations
Digital image? - Answers :Recorded as multiple numeric values and divided into an
array of small elements
analog image? - Answers :refers to a device or system that captures or measures a
continuously changing signal
what is a pixel? - Answers :smallest element in a digital image
what is a matrix? - Answers :square arrangement of numbers and columns in a row
what is the relation between pixel and matrix? - Answers :Pixels make up the matrix
bit depth? - Answers :# of bits or pieces of info within each pixel
brightness? - Answers :appearance of an image on a display monitor
spatial resolution? - Answers :ability of the image system to demonstrate small details
contrast resolution - Answers :display subtle changes in shade of gray; directly related
to the bit depth
, Perfect system according to MTF? How does light affect it? - Answers :1 or 100%; ^
light = decrease in MTF
latitude? - Answers :range of exposure that can be used to create an image with
appropriate optical density
How does collimation affect the image in the CR processing? - Answers :
What is a histogram? how's it used? - Answers :graphical representation of exposure
values collected from the imaging plate
nyquist theorem? - Answers :Sampling Theorem: When sampling a signal, the sampling
frequency must be more than the bandwith
Wraparound image? - Answers :2 superimposed images slight out of alignment
resulting in moire effect
How soon should you process a CR plate? - Answers :Within an hour because the
image will start to fade
What is automatic rescaling? - Answers :exposure greater than or less than what is
needed to produce the image; produces uniformity
how does the algorithm affect the image? - Answers :
Too much manipulation will cause what? - Answers :
What does window (width) and (window) level control? - Answers :Ratio of black and
white (contrast);
brightness
What is shuttering? - Answers :Blacken out the white collimation borders
Image stitching? - Answers :used for anatomy or areas of interest too large for one
cassette
what is annotation? - Answers :information other than the standard identification
zoom? - Answers :allows magnification of entire image
function of the CR plate's active layer? - Answers :traps electrons during exposure
purpose of the barcode layer? - Answers :match the image information with the patient
identifying barcode on exam
