Introduction to Digital Radiography and PACS

(Conventional Film/Screen) Image on the film that is viewed on a lightbox

Manifest image

(Conventional Film/Screen) What does the screen emit when struck by x-rays?

Light

(Conventional Film/Screen) How is the film processed?

Chemically

What allows real-time images to be viewed on high-resolution TV monitors?

Analog-to-Digital converters

Moving images via telephone lines to and from remote locations.

Teleradiology

What was photostimulable phosphor (PSP) previously known as

Computed radiography (CR)

Who first introduced the PSP

Fuji

Two types of flat panel detectors (FPDS)

Indirect Capture

Direct Capture

Indirect capture absorbs x-rays and converts them to?

light

Where are the images viewed in indirect capture?

On the computer monitor

In direct capture DR, the photoconductor absorbs x-rays and converts them to?

Electrical signals

In direct capture DR, the thin film transistor (TFT) collects and sends the signal to the?

Analog-to-digital converter (ADC)

In direct capture DR, where is the digital imaged viewed and processed?

At the technologists workstation

In indirect capture DR light is collected by an area-CCD, CMOS, or TFT and is converted into?

Electrical signals

In indirect capture DR, the computer processes electric signals into what?

Images

Which imaging system is the most efficienct?

FPD, images are available immediately

What imaging systems use traditional x-ray rooms with existing equipment

F/S and PSP

In conventional F/S, the film is placed inside of a cassette containing a?

Intensifying screen

In conventional F/S, x-rays strike the intensifying screen, producing?

Light

In conventional F/S interaction happens many times within the emulsion to form the?

Latent image

How is the manifest image created in Conventional F/S

Chemical processing

In PSP, some of the photon energy is deposited within the phosphor particles, creating?

The latent image

With direct capture, the x-ray energy is detected by what?

A photoconductor that converts it directly to a digital electronic signal

Are cassettes required for FPD?

No

In conventional film/screen radiography, the image is determined by what?

1) Shape of films response curve

2) processing chemicals

In PSP and FPD, where does the image processing take palce?

In a computer

Where is the computer located for PSP?

Near the readers

Where is the computer located for FPD?

Next to x-ray console

What type of response does conventional film/screen radiography have?

Nonlinear characteristic response

In conventional film/screen, what is controlled by kVp

Contrast

In conventional film/screen, what is controlled by mAs

Optical density

How does PSP and FPD respond?

Linear

In PSP and FPD what does kVp influence?

Subject contrast

In PSP and FPD what does mAs influence?

Image noise

In PSP and FPD Radiographic contrast and density are primarily controlled by what?

1) Image processing algorithm

2) Look-up-table (LUT)

Which image capture systems are more sensitive to scatter?

PSP and FPD

What causes quantum mottle?

too low mAs

Which image capture systems use a traditional x-ray room?

F/S

PSP

F/S processes images by?

Chemicals

PSP processes images by?

In PSP reader

FPD processes images?

At the console

In F/S, the latent image is formed by the x-ray strike hitting the?

Intensifying screen

In PSP, the latent image is formed by the x-ray strike hitting the?

Phosphor plate

In FPD, The latent image is formed by the x-ray strike hitting the?

Detector

Networked group of computers, servers, and archives used the manage and store digital images?

PACS

What does PACS stand for?

Picture Archival and Communication Systems

PACS can accept any image in _______ format.

DICOM