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Flashcards in Chapter 6 Deck (43)
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1

Steps or CR=
1.
2.
3.
4.

1. Expose
2. Stimulate
3. Read
4. Erase

2

(CR) After plate is exposed to X-rays ____ of meta stable electrons relax (EXPOSE)

50%

3

IP is put in plate reader and __1__ passes over remaining metastable excited electrons to stabilize them. They give off __2__ when they relax/stabilize ("__3__").

1. Neon Laser
2. LIGHT
3. Stimulate

4

Collects light for IP and sends it to Analog-To-Digital Convertor (ADC) which then goes to computer ("Read").

Photomultiplier Tube (PMT)

5

________ passes over IP to stabilize any remaining exited electrons and clear any remaining image ("Erase").

Intense White Light

6

Exposed IPs should be processed within _____ because latent image starts to fade.

1 hour

7

Spatial resolution is __1__ with increased sampling frequency, increased number of smaller pixels, smaller __2__, and smaller __3__.

1. Increase
2. Pixel pitch
3. Sampling pitch

8

CR plates can be read approx. _____ before they need to be replaced

10,000 times

9

DR combines __1__ capture and __2__ readout so images are available almost instantly after exposure.

1. Image
2. Image

10

DR is more __1__ and __2__ than CR

1. Expensive
2. Fragile

11

Made with layers in order to receive xray photons and convert them to electrical charges for storage and readout

Flat Panel Detectors

12

Layers of Flat Panel Detectors
1. First Layer=
2. Second Layer=__A__ array which is divided into square detector elements (DELs), each with a __B__ to store electrical charges and switching transistor for readout to be sent to __C__

1. X-Ray Convertor
2. A: Thin Film Transistor (TFT)
B: Capacitor
C: ADC

13

1. Can DR systems be permanently mounted?
2. Can DR be available as mobile?
3. Name two ways images are transmitted to the screen

1. Yes
2. Yes
3. Umbilical cord or wireless

14

Which has the more superior spatial resolution?

DR

15

Indirect DR uses a scintillator like __1__ or __2__ to convert exit radiation into visible light, which is converted to __3__ charges by photodetector a (layer of __4__)

1. Cesium Iodide (CsI)
2. Gadolinium Oxysulfide
3. Electrical
4. Amorphous Silicon (a-Si)

16

Indirect (__1__ with __2__) >> XRay >> __3__ >> Electrical Charge

1. A-Si
2. CsI
3. Light

17

Direct DR uses _____ to convert X-rays directly into electrical charges.

Amorphous Selenium

18

Direct (__1__) >> XRay >> __2__

1. A-Se
2. Electrical Charge

19

Ability of detector to capture accurately the range of photon intensities exiting patient

Dynamic Range

20

Digital IRs have a much larger exposure ______ than film screen (analog)

Latitude

21

Image ____ occurs during post processing to help produce images with appropriate grayscale appearance.

RESCALING

22

If IR is UNDEREXPOSED ("__1__" too high), __2__ will result

1. S
2. Quantum Mottle/Noise

23

If IR is overexposed then the "S" number is too __1__ and __2__ will occur

1. Low
2. Dose Creep

24

Always follow the ______ concept

ALARA

25

Increased ________ results in improved image quality ( increased signal and decreased noise)

Signal to Noise Ratio (SNR)

26

Two types of film screen IRs (Analog)

Regular cassettes or Extremity Cassettes

27

Regular Cassettes
1. How many intensifying screens?
2. Type(s) of film
Extremity Cassettes
3. How many intensifying screens?
4. Types of film?

1. Two
2. Duplitized or Double Emulsion Film
3. One
4. Single Emulsion

28

Regular Cassettes
1. Pt. Dose
2. Detail
Extremity Cassettes
3. Pt. Dose
4. Detail

1. Decreased
2. Decreased
3. Increased
4. Increased

29

Film base=__1__ (usually __2__ to decrease eye strain). Film Emulsion=Silver __3__ suspended in __4__. Supercoat=protects __5__ layer.

1. Polyester
2. Tinted blue
3. Halide crystals
4. Gelatin
5. Emulsion

30

Is most widely believed to explain latent image formation on film

Gurney-Mott Theory