Exam 4: Effective Use of Computed Radiography

Since the image contrast is generally determined more by the processing algorithm, the ____________________ does not have the impact on final image contrast as with screen/film systems.

____ occurs when a large number of the pixels will be at the maximum digital value (black)so that there is no signal difference in the very high exposure areas, resulting in a loss of anatomical structures in that region.

Because of the light spread between the plate and the light guide, the spatial resolution is less than the ____________________ frequency.

If a vendor provides a fixed-speed class operation, the system operates as a screen/film system of the selected ____________________.

Because of the increased sensitivity to scattered radiation, the kVp should not exceed ____ for any nongrid radiography, including chest.

With cassette-based PSP systems (CR), ____________________ resolution becomes a bit more complicated.

If larger body structures are done 3 on 1, the ____________________ scatter will reduce the contrast unless the unexposed areas are shielded between exposures.

The CR cassettes, or imaging plates (IP), are employed in the same manner as screen/film cassettes in existing radiographic units designed to accommodate software.

Because of their wide dynamic range, PSP plates are much more susceptible to ____________________ than are conventional film-screen systems.

The optimal alignment for all digital detectors is to have the part and beam centered to the receptor, with four collimation margins perpendicular to the cassette edges.

The factors determining ____________________ included motion factors, geometric factors, and the spatial resolution of the receptor unit (line pair/mm).

Many of the factors that cause low contrast in film-screen systems also cause low contrast in CR images.

Which exposure causes the system to rescale the image as if the plate is actually underexposed?

What is likely to occur if there is substantial extraneous exposure on the plate?

By reducing the acquired data width, more of the ____________________ may be visualized for a single image display setting.

What limits the irradiated volume and reduces undercutting?

With digital systems, what determines the speed class at which the system is operated?

What does it mean when the photon intensity reaching the receptor is lower than that required to produce an optimal image?

____________________ exposures are dramatically affected by the additional scatter, which may not even be removable by a grid.

Which of the following has more of an effect on image contrast than the kVp?