B - CR/DR

Question 1

What is CR imaging?

Answer 1

Process of capturing radiographic data from a conventional x-ray machine and processing the data digitally to produce high quality images

Question 2

What is DR imaging?

Answer 2

Process of capturing radiographic data from a detector as opposed to a table and bucky system. Data is still processed digitally to produce high quality images

Question 3

What does CR stand for?

Answer 3

Computed Radiography

Question 4

What does DR imaging stand for?

Answer 4

Digital Radiography

Question 5

Digital radiography is performed with a system of what functional components?

Answer 5

A digital image receptor
A digital image processing unit
An image management system

Question 6

What is the image receptor?

Answer 6

The image receptor intercepts the x-ray beam after it passes through the patient’s body.
It produces an image in digital form, that is a matrix of pixels, each with a numerical value.

Question 7

Can digital processing be used to change the image?

Answer 7

Yes, One of the major advantages of all digital imaging is the ability to process the image after they are recorded.
Various forms of digital processing can be used the change the image.

Question 8

What are the advantages of digital image storage?

Answer 8

Digital radiographs are stored as digital data.
Advantages (compared to film) include:
Rapid storage and retrieval
Less physical space required
Ability to copy and duplicate without loss of image quality.

Question 9

How does a communication network enhance digital radiography?

Answer 9

Another advantage of digital images is the ability to transfer them from one location to another rapidly.
This can be:
Within the facility to storage and display devices
To other locations around the world via the internet.
DICOM (digital imaging and communications in medicine)
PACS (picture archive and communications system)

Question 10

What is a softcopy?

Answer 10

Digital images displayed on a monitor are referred to as softcopy.

Question 11

What is an advantage of display devices?

Answer 11

One major advantage is the ability of the viewer to adjust and optimize the image characteristics such as contrast and density.
Other advantages include:
Zoom
Compare multiple images
Perform analytical functions such as measure distances and angles accurately.

Question 12

True or false? CR uses a Phosphor Receptor inside a cassette.(photo-stimulable plate PSP)

Answer 12

True

Question 13

How does the Computed Radiography Receptor work?

Answer 13

First a receptor containing the phosphor plate is exposed to record an image.
At this point it is an invisible latent image.
The next step is the cassette is placed into reader and processor unit.
The plate is scanned with a very small laser beam.
The digital data is stored as a digital image.
The process takes about 50 seconds compared to two minutes or more with film.

Question 14

What are the 5 specific quality characteristics of Image Quality in X-rays?

Answer 14

Spatial
Detail (blurring)
Contrast sensitivity
Noise
Artifacts

Question 15

With regards to exposure, Each manufacturer of digital receptors will provide an approach to calculate the image exposure information. True or False?

Answer 15

True

Question 16

How is Digital Radiograph Contrast adjusted to optimize contrast?

Answer 16

the ability to adjust and optimize contrast after the image is recorded.
This is done through the digital processing of the image and then the adjustment of the window when the image is being viewed.

Question 17

What are common sources of blurring?

Answer 17

The focal spot (depends upon size and object location.)
Motion if present
The receptor (generally due to light spreading within the fluorescent or phosphor screen)
Additional blurring is the result of dividing the image into pixels.
The size of a pixel (amount of blurring) is the ratio of the image size (image size relative to the anatomy) and the matrix size.
Pixel size is another factor that must be considered because it limits the detail of the image.
1024 x 1280 on a 18cm x 24 cm image would be sharper than on a 35 cm x 43 cm image.
Generally, digital images lack the spatial detail of film images due to the digital processing.

Question 18

What are common sources of blurring?

Answer 18

The focal spot (depends upon size and object location.)
Motion if present
The receptor (generally due to light spreading within the fluorescent or phosphor screen)
Additional blurring is the result of dividing the image into pixels.
The size of a pixel (amount of blurring) is the ratio of the image size (image size relative to the anatomy) and the matrix size.
Pixel size is another factor that must be considered because it limits the detail of the image.
1024 x 1280 on a 18cm x 24 cm image would be sharper than on a 35 cm x 43 cm image.
Generally, digital images lack the spatial detail of film images due to the digital processing.

Question 19

What effect does blurring cause?

Answer 19

Reduces Visibility of detail
Reduces Contrast resolution
Reduces image sharpness
Reduces object size