Digital Image Production

Which would be a good QA test to perform to determine the overall uniformity and consistency of the pixels over the entire digital image plate? Select one: A. Flat Fielding B. Pan Fielding C. Panning D. DQE Test

A. Flat Fielding

What term is applied when the computer system algorithms re-map the input data from the range of pixel values to produce a consistent brightness and gray scale on the output image? Select one: A. Rescaling B. Smoothing C. Rounding D. Gray scale Ratio Function

A. Rescaling

Which of the following tells the operator that the correct exposure has been received by the phosphors in the imaging plate? Select one: A. exposure indicator number B. signal-to-noise ratio (SNR) C. health level-7 D. DICOM gray-scale function

A. exposure indicator number

Which of the following artifacts can occur if the CR imaging plate receives too much background or scatter radiation? Select one: A. fogging B. ghost or phantom images C. light spots D. quantum mottle

A. fogging

Noise refers to the amount of information that is not useful in the radiographic image. This noise is referred to as: Select one: A. quantum mottle B. shuttering C. dynamic range D. signal-to-noise ratio (SNR)

A. quantum mottle

Which of the following will be seen in the x-ray image if either the kVp or the mA is set too low for the projection? Select one: A. quantum mottle B. low-contrast resolution C. greater brightness D. high signal-to-noise ratio

A. quantum mottle

The process of interpreting the signal strength by location and size of the various intensities is termed? Select one: A. sampling B. quantization C. peripheral D. plug-in SL

A. sampling

Which control on the viewing station can blacken the clear or white areas around the collimation edges of a radiograph? Select one: A. shuttering/masking B. image stitching C. window width D. window level

A. shuttering/masking

After the imaging plate is scanned in the CR reader and the image sent to storage, the phosphor is exposed to a _________ to erase the anatomical image. Select one: A. white light B. laser beam C. electric current D. electric charge

A. white light

In addition to reader misinterpretation of anatomic areas and incorrect gray scales being applied, what else may happen if multiple images are placed on one CR PSP? Select one: A. Facilities will save cost on fewer exposures to the CR plates. B. Fog density from multiple exposures may affect CR reader interpretation. C. The PMT will correct the images and reprocess multiple images. D. It is not possible to place more than one image on a CR PSP.

B. Fog density from multiple exposures may affect CR reader interpretation.

Each digital manufacture measures their systems ability to convert signals of remnant x-rays into various densities (pixel values) in the image; this is known as? Select one: A. Detective Quantum Efficiency (DQE) B. Modulation Transfer Function (MTF) C. Quantum Model D. Quantization

B. Modulation Transfer Function (MTF)

The computer system makes use of frequency data and reduce contrast, to decrease noise so the edges of structures appear less harsh in the final image. This is termed: Select one: A. Rescaling B. Smoothing C. Rounding D. Gray scale Ratio Function

B. Smoothing

Which of the following is a true statement regarding the centering of the body part when using digital systems? Select one: A. The part must be placed off-center by about 2 cm. B. The part must be placed in the center of the plate or detector. C. The part should be placed near one of the four edges. D. The part can be placed anywhere on the plate or detector

B. The part must be placed in the center of the plate or detector.

What is the problem if any with dose creep? Select one: A. Digital technology eliminates the dose creep concern. B. The patient receives more radiation than necessary to produce a diagnostic image on a digital system. C. It decreases the useful life of CR and DR receptors. D. Computer systems in the digital image chain cannot correct for overexposures

B. The patient receives more radiation than necessary to produce a diagnostic image on a digital system

Which of the following takes the stored charge in the flat-panel detector and converts it into a digital value? Select one: A. charge-coupled device (CCD) B. analog-to-digital converter (ADC) C. complementary metal oxide semiconductor (CMOS) D. smoothing processor

B. analog-to-digital converter (ADC)

These two items are important in CR imaging to decrease scatter and subsequent fog on the image. Select one: A. short SID and small focus B. collimation and grids C. high mA and low time D. short exposure and collimation

B. collimation and grids

The number of gray shades that a digital system can reproduce is termed: Select one: A. quantum mottle B. dynamic range C. contrast resolution D. spatial resolution

B. dynamic range

In addition to using a smaller focus, smaller pixels, and a larger matrix what other factor improves image sharpness in digital imaging? Select one: A. short SID B. long SID C. long OID D. large pitch

B. long SID

The artifact that will occur when the grid lines are not aligned with the CR reader's laser light is: Select one: A. quantum mottle B. moire pattern C. ghost images D. light spots

B. moire pattern

Each square picture element in a digital viewing monitor is called a: Select one: A. voxel B. pixel C. matrix D. window level

B. pixel

What is the name of the computer software function that allows adjustment of the radiographic image after it has been processed? Select one: A. image annotation B. postprocessing C. edge enhancement D. DICOM gray-scale function

B. postprocessing

What is the process of assigning an interpreted numerical value within the matrix area based on the strength of the signal received? Select one: A. sampling B. quantization C. quantum D. photomultiplier

B. quantization

Which control on the viewing station controls the density, or brightness, in the radiographic image? Select one: A. window width B. window level C. shuttering D. dynamic range

B. window level

Unused CR plates should be cleared through the CR reader after how many hours of non-use? Select one: A. 8 hours B. 12 hours C. 24 hours D. not necessary

C. 24 hours

In DR systems, the image detector directly captures the x-ray energy and converts the energy to signal intensities within the IR to create the image; thereby, eliminating the need for which device? Select one: A. physicians console B. a printer C. CR reader D. PACS

C. CR reader

The measurement of the systems efficiency to differentiate the various tissues (gray scale) in the resultant processed image is termed? Select one: A. DICOM B. Detective Quantum Efficiency (DQE) C. Contrast to noise ratio (CNR) D. Rescaling

C. Contrast to noise ratio (CNR)

The ability of the detector element to (del) to absorb x-rays and convert them to light. This is a sensitivity measurement to photons and called? Select one: A. Signal to noise equation B. Noise to signal equation C. Detective Quantum Efficiency (DQE) D. Modulation Transfer Function (MTF)

C. Detective Quantum Efficiency (DQE)

The system used to view and store digital x-ray images is called a ______ system. Select one: A. CR B. DR C. PACS D. postprocessing

C. PACS

Which of the following must be used with digital-based x-ray processors to ensure that the ALARA concept is practiced? Select one: A. a grid B. a 40-inch SID C. an exposure technique chart D. added aluminum at the port of the x-ray tube

C. an exposure technique char

Barium fluorohalide with europium is used: Select one: A. in the CR reader to erase the image B. in the CR reader to remove the image and process it C. as the phosphor that absorbs the x-ray energy in the imaging plate D. as the phosphor that absorbs the x-ray energy in the flat-panel detector

C. as the phosphor that absorbs the x-ray energy in the imaging plate

The ability to distinguish anatomical structures of similar subject contrast is termed: Select one: A. quantum mottle B. dynamic range C. contrast resolution D. spatial resolution

C. contrast resolution

What is the name of the processing technique that can be used to increase contrast and sharpen the image? Select one: A. contrast resolution B. DICOM gray-scale function C. edge enhancement D. image annotation

C. edge enhancement

The computer software function that allows any type of text to be written on a radiographic image is: Select one: A. window width B. window level C. image annotation D. image stitching

C. image annotation

The greatest spatial resolution will be produced when the matrix is _____ and the pixels are _____. Select one: A. small; large B. small; small C. large; small D. large; large

C. large; small

The viewing monitor's active viewing area is called a: Select one: A. voxel B. pixel C. matrix D. window width

C. matrix

What is the name of the processing technique that allows the x-ray images to be produced with uniform density and contrast, regardless of the amount of exposure? Select one: A. direct conversion B. indirect conversion C. rescaling D. edge enhancement

C. rescaling

The ability of the digital system to convert the x-ray input electric signal into a useful radiographic image is termed the: Select one: A. dynamic range B. contrast resolution C. signal-to-noise ratio (SNR) D. shuttering

C. signal-to-noise ratio (SNR)

What is the name of the technique in which each pixel's frequency is averaged with the surrounding tissues' pixel values in an effort to reduce noise in the image? Select one: A. edge enhancement B. postprocessing C. smoothing D. rescalin

C. smoothing

Measuring the distance from the center of one pixel or Del to the other determines what? Select one: A. pixel to pixel pitch B. Del to Del Pitch C. the pixel and or Del pitch D. matrix size

C. the pixel and or Del pitch

What does a CCD (charge coupled device) and/or a CMOS (complementary metal oxide semiconductor) perform? Select one: A. They convert x-ray energy into light. B. They are used in an indirect conversion image system. C. The converted light is turned into an electronic signal. D. All of the above

D. All of the above.

What is the term for the calibration of an image display system that ensures that all radiographic images' gray scales are presented consistently? Select one: A. postprocessing B. edge enhancement C. health level-7 D. DICOM gray-scale function

D. DICOM gray-scale function

Which of the following should never be placed on the radiographic image using electronic means (computer software)? Select one: A. diagnosis B. patient's age C. patient's name D. R and L markers

D. R and L markers

Window width controls which aspect of the radiographic image? Select one: A. shuttering B. noise C. density D. contrast

D. contrast

This occurs when there may be a defect in a component of the computer screen matrix that may cause a loss of patient information: Select one: A. phantom images B. quantum mottle C. smoothing D. dead pixels

D. dead pixels

When a CR plate is inserted into the reader for processing, the phosphor is scanned with a: Select one: A. green/blue light B. fluorescent light C. white light D. laser beam

D. laser beam

Which of the following artifacts can appear in the radiographic image if the CR imaging plate is not erased properly? Select one: A. light spots B. edge enhancement C. quantum mottle D. phantom or ghost images

D. phantom or ghost images

The amount of detail or sharpness in the digital image is termed: Select one: A. contrast resolution B. dynamic range C. recorded detail D. spatial resolution

D. spatial resolution

Quantum mottle occurs in digital images if: Select one: A. the time is set too long B. the mA is set too high C. the kVp is set too high D. there are not enough photons reaching the IR

D. there are not enough photons reaching the IR