Exam 3 Review

What is the most commonly used material for the x-ray table top?

• Wood

• Carbon fiber (acrylic) material

• Metal

• Plastic

Answer explanation

The most commonly used material for the x-ray table top is carbon fiber (acrylic) material, as it provides the necessary strength and transparency for x-ray procedures.

The actual center of the x-ray beam must align with the centering indicator within what percent of the SID?

• 1%

• 2%

• 3%

• 4%

Answer explanation

The actual center of the x-ray beam must align with the centering indicator within 1% of the SID, making 1% the correct choice.

How many sets of adjustable lead shutters are typically found in light-localizing variable-aperture rectangular collimators?

• One

• Two

• Three

• Four

Answer explanation

In light-localizing variable-aperture rectangular collimators, typically two sets of adjustable lead shutters are found to control the aperture size.

What is the maximum allowable deviation for the collimator light field size and location from the actual x-ray beam size and location?

• 1%

• 2%

• 3%

• 4%

Answer explanation

The correct choice is 2% because it is the maximum allowable deviation for the collimator light field size and location from the actual x-ray beam size and location.

In exposure reproducibility, a variance of ____ percent or less is acceptable.

• 5%

• 10%

• 15%

• 20%

Answer explanation

In exposure reproducibility, a variance of 5% or less is considered acceptable, making 5% the correct choice.

A device made of parallel radiopaque strips alternately separated with low-attenuation strips of a material such as aluminum or plastic is called a:

• Radiographic Grid

• X-ray Filter

• Lead Shield

• Image Receptor

Answer explanation

A device made of parallel radiopaque strips alternately separated with low-attenuation strips of a material such as aluminum or plastic is called a Radiographic Grid.

Effects that occur because digital images are produced collectively by a matrix of elements that contain finite dimensions and are always subject to random quantum noise (mottle) are known as:

• Moire patterns

• Digital Artifacts

• Contouring artifacts

• Aliasing

Answer explanation

Effects that occur due to finite dimensions and random quantum noise in digital images are known as Digital Artifacts.

Using grids in CR causes increased patient dose due to increase in what?

• kVp

• mAs

• SID

• OID

Answer explanation

Using grids in CR causes increased patient dose due to increase in mAs.

In digital radiography, which type of image receptor uses direct conversion?

• Scintillator

• Photoconductor

• Charge coupled device

• Thin-film transistor

Answer explanation

In digital radiography, the image receptor that uses direct conversion is the Photoconductor.

In indirect conversion, what are the steps that x-rays go through before an image is formed? (2 answer choices)

• X-rays-scintillator-photodiode-thin-film transistor array-electrical signals

• X-rays-photoconductor-thin-film transistor array-electrical signals

• X-rays-scintillator-charge coupled device array-electrical signal

• Both A & C

Answer explanation

Indirect conversion has two different processes x-rays go through before an image is formed.

(1) X-rays pass through a scintillator, then a photodiode, followed by a thin-film transistor array before converting to electrical signals.

(2) X-rays pass through a scintillator, charge-coupled device array, then converts to electrical signals