Terms and Definitions
Computed Radiography
Digital Radiography
Processing
Image Quality
100

A binary number is called

What is a bit?

100

Common PSP phosphors are

What is barium fluorohalide bromide (85%) and barium fluorohalide iodide (15%)?
100

In regards to spatial domains, small structures have _____ frequency and ______ contrast

high & high

100

Point processing

local processing

geometric processing

What are the 3 types of image processing operations?

100

The practice of over exposing the patient to ensure all of the data is captured is called

What is exposure creep?

200

An 8 bit word is called a 

What is a byte?

200

The latent image is created by the europium electron holes that are also referred to as

What is electron traps or F-centers

200

The problem with manipulating the image prior to sending it to PACs is

It limits the information that the radiologist receives and can manipulate...don't do it:)

200

This processing operation allows for rotation and magnification of the image

What is geometric processing?

200

DQE and MTF have this relationship

What is directly proportional?

300

The information that is valuable on a histogram is called

What is the value of interest?

300

In CR, K-edge attenuation is best between ____ to _____ keV.

What is 35-50 keV.

300

Professional organizations have asked for a universal system for this parameter to standardize across manufacturers and make it more user friendly for technologists.

Exposure Indicators

300

Gray scale bit depth controls

What is the # of shades of gray or density resolution?

300

Resolution is controlled by

What is pixel size

400

The measurement of the sensitivity and accuracy of the IR to produce the image is known as the

What is the DQE-Detective Quantum Efficiency

400

Atomic #

thickness of material

density

What factors affect x-ray absorption?

400

The range of the IR's ability to respond to different exposure levels

What is the dynamic range?

400

This processing operation is used to visualize bony cortical changes, micro calcifications, and bony trabeculae

What is edge enhancement?

400

System

ambient

quantom mottle 

Are all examples of

What is noise

500

Each APR has a reference ___________ and a reference ___________.

What is a histogram and LUT

500

This preprocessing step adjusts for contrast

What is the look up table (LUT)

500

The range of over exposure or under exposure that can occur in producing an acceptable image

What is exposure latitude?

500

An under or over exposed image can be modified to achieve an acceptable image through a histogram analysis. This is done by the digital processing technique of:

What is histogram stretching, histogram modification, or rescaling

500

A high SNR would indicate

What is low noise

as noise increases, contrast decreases...think of it as scatter