Flashcards in Final Exam Deck (75)

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1

## What are the two ways of measuring radiation?

### Old school units and SI Units

2

## What are old school units (4)?

###
Roentgen (R)

Rad

REM

Curie

3

## What are SI units (4)?

###
Coulombs per kilogram (C/kg)

Gray (Gy)

Sievert (Sv)

Becquerel

4

## Roentgen (R) is equal to

### Coulombs per kilogram (C/kg)

6

## What is the conversion rates of old school (e.g. rad) to SI unites (e.g. Gy)?

###
1 old school = 0.01 SI unit

100 old school = 1 SI unit

E.g. 1 rad = 0.01 Gy; 1 REM = 0.01 Sv; 1 curie = 0.01 becquerel

7

## Quality factor (QF) is derived from what measurement?

###
Relative Biological Effectiveness (RBE)

* it varies with different types of radiation

8

## What is the quality factor for X-ray photons

### 1

9

## What is the quality factor for gamma photons

### 1

10

## What is the quality factor for beta particles

### 5

11

## What is the quality factor for thermal neutrons

### 5

12

## What is the quality factor for fast neutrons

### 20

13

## What is the quality factor for alpha particles

### 20

14

## What are the Laws of Bergonie and Tribondeau (4)?

###
Cell sensitivity depends on:

- Age (young more sensitive)

- Differentiation (simple cells more sensitive)

- Mitotic rate (rapidly dividing cells more sensitive)

- Metabolic rate ( cells that use lots of energy are more sensitive)

15

## Define “absorbed dose”

### Energy absorbed per unit mass at a given point

16

## Define “organ dose”

### The probability of stochastic effects (mainly cancer creation) as the absorbed dose averaged over an organ

17

## Define “equivalent dose”

### The organ dose corrected by a radio action weighting factor that takes account of the relative biological effectiveness of the incident radiation in producing stochastic effects

18

## Define “effective dose”

### A weighted sum of equivalent doses to all relevant tissues and organ with the purpose “to indicate the combination of different doses to several different tissues in a way that is likely to correlate well with the total of the stochastic effects”

19

## What does kerma stand for?

### Kinetic energy released per unit mass

20

## Define “Kerma”

###
Sum of kinetic energy of all charged particles liberated per unit mass

1 Kerma is ~ rad at low energies

SI unit of Kerma = Gy

21

## What kind of effects can be either somatic or genetic?

### Stochastic

22

## What is the 10-day rule?

### Direct pelvic radiation to fertile females should be done only during the first 10 days of menstrual cycle EXCEPT in emergencies

23

## What is stochastic?

###
Probabilistic, random.

The probability of experiencing the effect is proportional to the exposure volume, but the severity of the effect is not really affected.

“randomly determined; having a random probability distribution or pattern that may be analyzed statistically but may not be predicted precisely.”

24

## What might be the results of a “severe stochastic effect” of exposure to radiography (3)?

###
Cancer

Leukemia

Mutagenesis (genetic effects)

25

## Stochastic effects can be either _____ or ______ while nonstochastic effects are limited to ____

###
Stochastic: Somatic or Genetic

NONstochastic: somatic and seen in larger exposure quantities

26

## Low dose exposure effects fall into what category?

### Stochastic

27

## What does nonstochastic mean?

###
Deterministic, predictable

The severity of the effect is proportional to the exposure volume. There is a threshold beneath which effects generally aren’t seen

28

## What falls under the category of nonstochastic short-term effects (3)?

###
GI syndrome

Hematopoietic syndrome

CNS syndrome

29

## What falls under the category of nonstochastic long term effects (5)?

###
Cataract formation

Fibrosis

Organ atrophy

Loss of parenchymal cells

Reduced fertility, sterility

30

## Radiation exposure in the first 14 days of pregnancy increase risk of:

### Spontaneous abortion

31