Radiology module 4 Flashcards Preview

Radiology > Radiology module 4 > Flashcards

Flashcards in Radiology module 4 Deck (25):
0

A free radical is an ---- atom that exists with --- electron in its outer shell

Uncharged
One

1

---- are highly reactive and unstable elements

Free radicals

2

3 ways free radicals combine in order to gain stability?

Recombine and cause no changes
Combine with other free radicals
Combine with water or other molecules and form toxins (cellular changes)

3

2 theories of radiation injury

Direct
Indirect

4

The direct theory of radiation injury says?

Free radicals directly contact critical areas of the body and causes cell damage

5

The Indirect theory of radiation injury says?

Cell damage is due to the formation of toxins from free radicals

6

Which type of radiation injury occurs more commonly?
Why?

Indirect
Due to the high water content in body

7

A linear curve dose response says the response of the tissue is -----
to the dose?

proportional

8

Nonthreshold linear curve dose response says?

No matter how small the dose a response will occur

9

Threshold curve dose response says?

A response only occurs up to a certain point

10

Total dose is the ---- of radiation absorbed? And ---- damage occurs with larger tissue absorption

Quantity
More

11

Factors that determine radiation injury?

Total dose
Dose rate
Amount of tissue irradiated
Cell sensitivity
Age

12

Effects that are seen within minutes and are associated with large amounts of radiation over a short time are called?

Short term effects

13

Effects associated with small amounts of radiation given repeatedly over a long time are called?

Long term effects

14

Effects not seen in same person but in future generations are called?

Genetic effects

15

Effects seen in the person irradiated are called?

Somatic effects

16

Critical organs in head-neck region

Skin, thyroid, lens of eye, bone marrow

17

Radiosensitivity of cells is directly proportional to --- and ----
Also, Inversely proportional to -----

Reproductivity
Metabolic activity
Degree of differentiation

18

Traditional system of measuring radiation?

R
RAD
REM

19

SI system of measuring radiation

C/kg
Gy
Sv

20

2 types of background radiation

Cosmic (stars)
Terrestrial ( earth/air)

21

3 sources of radiation exposure

Background
Human made
Medical/Dental

22

Ways to reduce exposure to patients

Film speed (F)
Digital x-rays
Collimation
Paralleling Technique
Raise kvp to decrease exposure time

23

Digital systems decrease exposure by --- to --%

50-80

24

F speed film decreases exposure by --- to ---%

20-60