Radiologic Science for Technologists - E-Book: Chapter 1 Flashcards


Set Details Share
created 2 months ago by elsa12
23 views
Study Guide
updated 2 months ago by elsa12
show moreless
Page to share:
Embed this setcancel
COPY
code changes based on your size selection
Size:
X
Show:
1

Matter

Anything that occupies space & has mass
The fundamental complex building blocks of matter are atoms & molecules

2

Mass

Quantity of matter contained in any physical object
§ Mass is measured in kilograms(kg)

3

Electromagnetic energy aka Electromagnetic Radiation

Travels in waveform

Least familiar form of energy

Used in xray imaging

4

Examples of electromagnetic energy

Gamma rays

x-rays

Ultraviolet rays

visible rays

microwaves

radio frequency

5

Electromagnetic radiation that has suffiecient energy to ionize are

Xrays

Gamma Rays

Ultraviolet Lights

6

Mass energy equivalence was invented by

Albert Eintein

7

Mass energy equilance

card image

the product of mass and square of the speed of light

C can also be equal to

C=186000 miles/sec

8

Radiation

transfer of energy; energy emitted and transferred through space

not all radiation is ionizing

9

ionizing radiation

any type of radiation that is capable of removing an orbital electron from an atom with which it interacts

10

Ionization

removal of an electron from an atom which causes the atom to become a positively charged ion.

Fast-moving particles with high kinetic energy can cause ionization too

11

Examples of Ionization

Alpha and Beta

12

Ion pair

card image
  • the ejected electron
  • the resultant positively charged atom together are called an ion pair.
13

Sources of Ionizing radiation

  • Natural environment radiation: 3 mSv/yr
  • Man made radiation: 3.2 mSv/yr
14

The largest souce of natural environment is

radon

15

Components of Natural Environmental Radiation

  1. Cosmic rays: Sun & stars
  2. Terrestrial radiation: Deposits of uranium, thorium & other radionuclides in earth
  3. internally deposited radionuclides: Potassium-40
  4. Radon: affect us by giving us lung cancer
16

Radon

  • is a radioactive gas that is produced by the natural radioactive decay of uranium.
  • it emits alpha particles and contributes radiation dose to the lungs.
17

Alpha Radiation

causes a lot of ionization and damage in body and contains very little penetration power

18

Who discoverd xray and when

Wihelm Roatgen on Nov 8, 1895

19

The first radigraphy

Roetgen's wife's hand

20

High frequency equals

high penetration

21

Two type of radiation are

Electromagnetic and Particulate

22

Particulare Radiation

type of radiation that travels in particles

Example: Alpha particles(they are 20 times more damaging to our body then Gamma Rays

Beta particles

23

What is different is electromagnetic and particulate

Equality factors

24

What is the purpose of a fluoroscopic machine?

to produce dynamic images on a digital screen

  • X-ray tube located under exam table
  • Image intensifier above exam table
25

Fluoroscopic invented by

Thomas Edison in 1898

26

CT

uses rotating xray and detectors to produce cross sectional images

27

Xray

are produced when fast moving electrons are suddenly stopped by a metal target

28

Largest manmade source of ionizing radiation is

diagnostic X-rays in the United States it is close to 3.2 mSv/yr (51%)

29

Importance of Snook transformer

the radiology emerged as a medical specialty because of this and Coolidge tube

30

Coolidge x-ray tube

  • This allows X-ray intensity and energy to be selected separately and with
    accurately
  • We use that today
  • Radiology emerged as a medical specialty because of the snook transformer &
    the Coolidge X-ray tube
31

Crooks tube

  1. It’s a large, partially evacuated glass tube
  2. Able to produce X-rays & fluorescent light § Roentgen used this
  3. It was never changed until the 20th century
32

kVp: Kilovalt peak

  • Primary control of beam QUALITY
  • Controls penetration
  • Controls radiographic contrast
  • Influence beam quantity
33

Increase in Kvp reduces

differential absorption and image contrast

34

One kVp equals

1000 V of electric potential

35

mA

  • controls radiation
  • controls number of Xray produced
  • with constant exposure time mA also controls extra quality and therefore patient dose
36

ALARA

As Low As Reasonably Achievable

37

Purpose of collimation

  • Restricts the useful x-ray beam to that part of the body to be an image
  • Reduces scatter radiation
  • Improves image contrast
38

The Ten Commandments of Radiation Protection

  1. Understand and apply the cardinal principles of radiation control: time, distance, and shielding.
  2. Do not allow familiarity to result in false security.
  3. Never stand in the primary beam.
  4. Always wear protective apparel when not behind a protective barrier.
  5. Always wear an occupational radiation monitor and position it outside the protective apron at the collar.
  6. Never hold a patient during radiographic examination. Use mechanical restraining devices when possible. Otherwise, have parents or friends hold the patient.
  7. The person who is holding the patient must always wear a protective apron and, if possible, protective gloves.
  8. Use gonadal shields on all people of childbearing age when such use will not interfere with the examination.
  9. Examination of the pelvis and lower abdomen of a pregnant patient should be avoided whenever possible, especially during the first trimester.
  10. Always collimate to the smallest field size appropriate for the examination.
39

What does increasing in collimation mean

  • less light around the anatomy
  • tigher collimation
  • decreased FOV (field of view(
40

Purpose of intensifying screen

to reduce exposer of the patient to x-ray by 95% compared with direct exposure film

41

What are the various types of protective apparel used in radiography

1) Thyroid shield 0.5 mm lead

2) Aprons 0.5 or 1.0mm lead

3) Lead Mobile X-ray barrier .05 or 1.0 mm lead

4) Glasses .35 mm lead

5) Gloves .25 mm lead

6) Leaded glass window .25mm lead

7) Gonadal shielding 0.25???

42

What material is used to manufacture protective apparel?

Lead impregnated

43

Velocity of light

is speed

186,000miles/sec

44

Mechanics

a segment of physics that deals with objects at rest and objects motion

  • Velocity V=D/t
  • Accerelation
45

Newton's Law

  1. Newton's First Law: Inertia A body will remain at rest or will continue to move with constant velocity in a straight line unless acted on by an external force.
  2. Force (F) that acts on an object is equal to the mass (m) of the object multiplied by the acceleration (a) produced F=M x A
  3. For every action, there is an equal and opposite reaction.
46

Force

Newton’s second law:

Force (F) that acts on an object is equal to the mass (m) of the object multiplied by the acceleration (a) produced
F=M x A

  • Push or pull of an abject
  • The SI unit for force Is newton
47

Weight

the force on the body caused by the pull of gravity on it

Unit: newtons and pounds

1pounds= 4.5N

48

Momentum

product of the mass of an object and its velocity

P=MV

49

Work

the product of force times distance

W=FD

50

Power

the quotient of work divided by time

P=W/ T=FD/T

SI unit: joule/seconds which is watt (w)

british unit: horsepower (hp)

51

Energy

the ability to work

Unit: Joule

52

kinetic energy

energy associated with motion of an object

KE=1/2 MV2

53

Potential energy

the stored energy of position or configuration

54

Heat

the kinetic energy of random motion of molecules

unit: calorie

55

Conduction

transfer of heat through material or by touching

56

Convection

mechanical transfer of hot molecules in a gas or liquid from one place to another

57

Thermal

transfer of heat by emission infrared radiation

58

Temperature

measured with a thermometer

normal: 98.4 F or 37 C

59

Temperature Conversions

  • Tc =5/9(Tf -32)
  • Tf = 9/5 Tc + 32
  • Tk = Tc + 273
  • Tc = Tk - 273
60

Absolute zero means

zero degrees kelvin also equals -273 degree celsius

61

REM

Radiation Equivalent Men

62

Curie (unit of radioactivity)

1 curie= 3.7x1010 nulei disintegrade

1 curie= 3.7x10 becquerels (Bq)

63

standard unit of Length

meter and foot

64

unit of Mass

kg and pounds

65

standard unit of time

seconds

66

Unit of exposure

Air kerma/C/kg

Roentgen

67

Unit of Air kerma

Gry(a)/Joules/kg

68

Unit of abosrbed dose

Gray and Rad

69

Unit of effective dose

Sievert or Rem

70

Unit of Dose equivalent

J/kg

71

Unit of occupational dose

rem

72

Unit of radioactivity

Curie or becquerel

73

Important Conversions

card image