Ict136 - Unit 1 - Ppt 1.1 - Radiation

Front 1

Three types of radiation that may be used in CCLs

Back 1

X-ray
beta
gamma

Front 2

most commonly used form of radiation

Back 2

x-ray

Front 3

Properties of radiation

Back 3

travel in straight line until interrupted
can be refracted
travels at the speed of light
can penetrate nearly any matter, and
has the ability to "fluoresce"

Front 4

Measurements of Radiation

Back 4

R (Roentgen)
RAD (radiation absorbed dose)
REM (radiation equivalent in man)

Front 5

Roentgen refers to?

Back 5

amount of ionizing radiation in air during exposure of radiation made

Front 6

RAD refers to?

Back 6

radiation delivered to patient

Front 7

REM refers to?

Back 7

to the biological effects of exposure

Front 8

Radiation measurements used mostly by international research

Back 8

Grey and Sievert

Front 9

1 sievert = how many REM?

Back 9

100 Rem

Front 10

What is the allowable dose limits for "whole body" exposure per year?

Back 10

5,000mREM/year (5REM)

Front 11

how do you calculate the lifetime allowable dose?

Back 11

5 Rem x (age-18)

Front 12

Early effects of exposure

Back 12

erythema
nausea/vomiting
diarrhea
rapid hair loss
skin ulcerations
fever

Front 13

Late effects of exposure

Back 13

cancers
birth defects
hematologic disorders
cataracts

Front 14

This is very rare, it kills large number of cells very rapidly and severity depends on volume exposed

Back 14

High level, acute exposure to radiation

Front 15

Is low level, chronic exposure to radiation possible in a medical setting?

Back 15

no

Front 16

This level and type of exposure has no early effects but late effects are likely to be seen after years of exposure

Back 16

low level, chronic exposure

Front 17

how much and what tupe of exposure results in permanent sterility to both men and women?

Back 17

500 RAD, Acute exposure

Front 18

acute exposure of 200 RAD results in? - Gonodal radiation

Back 18

temporary sterility in men and women

Front 19

this type of exposure can result in chromosomal changes and birth defects

Back 19

chronic exposure

Front 20

what results in an acute exposure of only 10 RAD in men?

Back 20

temporary decreased sperm count but no long term effects

Front 21

This group of healthcare workers where consider to be a "high exposure" group

Back 21

Radiologist

Front 22

back in 1930 radiologist died this many years earlier thsn other groups with high rate of cancers

Back 22

5 years

Front 23

Which trimester is most important regarding protection?

Back 23

First trimester

Front 24

it is during this trimester where most cancers or defects could originate

Back 24

First trimester

Front 25

this law state "more sensitive cells are affected more by radiation"

Back 25

Law of Bergonie and Tribondeau

Front 26

Occupational exposure to developing embryo cannot exceed this amount

Back 26

0.5 rem (500mREM)

Front 27

what is the alotted amount of occupational exposure for the term of the pregnancy?

Back 27

50 mREM/month

Front 28

this is the primary means of radiation exposure to healthcare workers

Back 28

scatter radiation

Front 29

scatter radiation results from?

Back 29

primary beam interacting with matter (i.e. the patient)

Front 30

Factors that increase radiation exposure

Back 30

increased magnification of image
increased frame rate
increased "source to image" distance
less image "collimation"
longer "fluroscopy" time during procedures
more "cine" runs during procedures
increased "image intensifier" angles

Front 31

what does ALARA stands for?

Back 31

As Low As Reasonably Achievable

Front 32

Major principles of radiation safety

Back 32

time
distance, and
shielding

Front 33

Doses of scatter radiation (blank) with larger patients

Back 33

increase

Front 34

larger patient require longer (blank)

Back 34

beam on time

Front 35

what results when we keep the source-to-image distance as close as possible to the patient?

Back 35

reduce radiation dose to patient
reduce scatter radiation to personell
increase image clarity

Front 36

Magnification (blank) dose rate to the patient's skin

Back 36

increases

Front 37

The smaller the Field of Vision (FOV) the (blank) the radiation

Back 37

higher

Front 38

What happen when we collimate down to area of interest?

Back 38

improves image quality
reduces patient exposure volume
reduces scatter radiation

Front 39

What is the most important aspect of radiation management?

Back 39

Beam on Time

Front 40

Distance helps (blank) exposures significantly

Back 40

reduce

Front 41

How does the Inverse Square Law works?

Back 41

If you double the distance from the source, exposure is REDUCED by 4 times (you get 1/4 the dose
If you reduce the distance from the source by 1/2, exposure is INCREASED by 4 times (you get 4 times the dose)

Front 42

Protective devices used in cath lab

Back 42

Lead aprons
Thyroid shields
Lead-equivalent glasses
Rolling/ha ging shields
Other staff

Front 43

What is the minimum equivalency for lead aprons/thyroid shields?

Back 43

0.5mm lead

Front 44

Cooling methods of X-ray tube

Back 44

metal --> copper
oil base cooling fan
spinning capability of the anode

Front 45

what percentage of the photons is what forms the image?

Back 45

1%

Front 46

If only 1% of photons is what forms the image, what happens to the other 99%?

Back 46

is tranformed into heat

Front 47

Why is the diaphragm important for image control?

Back 47

they equilize density

Front 48

Is Collimation manual or automatic control?

Back 48

manual

Front 49

Is Diaphram manual or automatic image control?

Back 49

automatic

Front 50

Lead glasses have a minimum (blank) lead equivalency

Back 50

0.6mm

Front 51

Plastic lens provide (blank) radiation exposure

Back 51

no

Front 52

regular glass lens provide (blank) radiation protection of lead lens

Back 52

1/4