unit 4 pri

Which of the following is NOT a way to reduce the production of scatter radiation?

• reduce the field size

• reduce pt. thickness

• increase grid ratio

• ask patient with a large abdomen to lie prone vs. supine

A device consisting of very thin lead strips with radiolucent interspaces intended to absorb scatter radiation emitted from the patient is a:

• collimator.

• aperture diaphragm.

• cone.

• grid.

What type of grid error results in appropriate exposure to the middle of the IR and marked underexposure along the sides of the IR?

• Stationary grid

• Upside-down focused grid

• Lateral decentering

• Off-level

If an excellent knee radiograph is produced using 10 mAs and an 8:1 ratio grid, how much mAs will be needed if no grid is available?

• 2.5 mAs

• 4 mAs

• 8 mAs

• 10 mAs

The number of lead strips per inch in a grid is a measure of:

• Grid selectivity

• Grid ratio

• Grid frequency

• Contrast improvement number

an optimal AP abdomen radiograph can be produced using 40 mAs, 75 kVp, and a 12:1 grid. How much mAs would be needed if the only grid available is a 6:1 ratio grid?

• 20 mAs

• 24 mAs

• 67 mAs

• 80 mAs

Grids that move during the exposure:

• Are reciprocating grids

• Move from top to bottom

• Are part of the Potter-Bucky diaphragm

• both Are reciprocating grids and Are part of the Potter-Bucky diaphragm

Which of the following are tools that the radiographer can use to limit scatter radiation?

• Beam-restricting devices

• Radiographic grids

• Digital imaging plate

• both Beam-restricting devices and Radiographic grids

The recommended SIDs that can be used with a focused grid describes the:

• Focal distance

• Convergent point

• Focal range

• Convergent line

When a grid is needed but not available, the _____ may be used for certain examinations.

• Tomographic technique

• Air-gap technique

• Seldinger technique

• Reverse collimation technique