Ch. 4: Summary

Question 1

What material are PSP cassette-based imaging systems made of?

Answer 1

Durable lightweight plastic.

Question 2

What are the layers of a PSP imaging plate?

Answer 2

Protective, phosphor, reflective, conductive, color, support, and backing layers.

Question 3

What are barcodes used for in PSP imaging systems?

Answer 3

To identify the cassette or imaging plate and link it with the patient examination.

Question 4

What crystals are found in the imaging plate?

Answer 4

Barium fluorohalide crystals.

Question 5

What do barium fluorohalide crystals release when stimulated?

Answer 5

Light energy stored in the conductive layer.

Question 6

What does the imaging plate reader use to scan the imaging plate?

Answer 6

A laser or a module of lasers.

Question 7

What type of light is released during the scanning process?

Answer 7

Blue light.

Question 8

What device amplifies the released light and sends it to the signal digitizer?

Answer 8

A photodetector.

Question 9

What does the ADC (analog-to-digital converter) do?

Answer 9

Assigns a numerical value to each pixel based on the intensity of the detected light.

Question 10

What determines the spatial resolution of a digital image?

Answer 10

The thickness of the phosphor layer and the number of pixels.

Question 11

How does phosphor layer thickness affect image sharpness?

Answer 11

Thinner phosphor layers provide greater sharpness.

Question 12

How does pixel size affect spatial resolution?

Answer 12

Smaller pixel size increases spatial resolution.

Question 13

Why does the contrast resolution of PSP systems exceed that of film/screen systems?

Answer 13

Because PSP systems have higher bit depth (more shades of gray).

Question 14

Why should imaging plates be read quickly after exposure?

Answer 14

Because stored energy dissipates over time, causing loss of image information.

Question 15

Where are PSP images sent after being processed?

Answer 15

To the QC (quality control) station for analysis and then to PACS for long-term storage.

Question 16

How are imaging plates erased after use?

Answer 16

By exposing them to bright light such as fluorescent light.