Digital radiography Ch. 23

Question 1

Digital radiography replaced film with 2 types of systems called..

Answer 1

CR & DR

computed radiography & digital radiography

Question 2

CR uses..

Answer 2

a photostimulable storage phosphor imaging plate

Question 3

DR has 2 types of detector configurations

Answer 3

direct conversion or indirect conversion

Question 4

Direct conversion means …

Answer 4

without scintillator

Question 5

Indirect conversion means…

Answer 5

with scintillator

Question 6

What does scintillator do?

Answer 6

converts incoming xray photons to light

Question 7

What does a photodetector do?

Answer 7

converts light into an electronic signal

Question 8

What systems use indirect conversion?

Answer 8

CR and DR

Question 9

In Digital radiography there can be 3 types..

Answer 9

cassette based CR or cassette DR or Cassette-less

Question 10

In a PSP plate the 2nd layer is the..

Answer 10

phosphorus layer

Question 11

The photo stimulable process occurs where?

Answer 11

inside the reader

Question 12

What does ADC stand for?

Answer 12

Analog to Digital Converter

Question 13

What can erase the PSP?

Answer 13

intense light

Question 14

How would you loose your image on a PSP that has already been exposed?

Answer 14

If you leave them in the room when you are doing another exposure

Question 15

What does PSP stand for?

Answer 15

Photostimulus Storage Phospher

Question 16

Simply, what does direct capture mean?

Answer 16

direct conversion to electrons

Question 17

Simply, what does indirect capture mean?

Answer 17

scintillator converts xrays into light

Question 18

For direct and indirect capture how is ADC used?

Answer 18

the Converter changes Anode to Digital (CAD)

Question 19

How long before a latent image looses 25% of its energy in a PSP?

Answer 19

8 hours

Question 20

What does rescaling do?

Answer 20

compares & adjusts pixel densities

Question 21

During pre processing what adjusts brightness/contrast?

Answer 21

the LUT

Question 22

Should RTs crop or mask images that would eliminate areas of exposure from the image?

Answer 22

no

Question 23

What does ALARA mean?

Answer 23

As Low As Reasonably Achievable

Question 24

What are some ALARA radiation protection things we can do?

Answer 24

pregnancy screening, collimation, shielding

Question 25

How could you become a dose creep?

Answer 25

By relying on windowing

Question 26

How can you be a technique creep?

Answer 26

adjust technique apropriatly with kVp and mAs

Question 27

Where is the ideal place for your EI number to be?

Answer 27

right in the middle of the range