Foundation of Radiology

Question 1

a basic unit of mstter consisting of a dense central nucelus surrounded by a cloud of negativley charged electrons

Answer 1

Atom

Question 2

What is the accepeted model of the atom?

Answer 2

Electron cloud model/ Quatatum mechanics model

Question 3

the production of ions, or the process of converting an atom into ions.
* Requires energy to overcome electrostatic foce that bind electron to nucelus

Answer 3

Ionization

Question 4

Particles that can create ionization

Answer 4

Photons

Question 5

the emission and propagation of energy through space or a substance in the form of waves or particles.

Answer 5

Radiation

Question 6

the process by which certain unstable atoms or elements undergo spontaneous disintegration(or decay) in an effort to attain a more balanced nuclear state

Answer 6

Radioactivity

Question 7

any form of radiation that has enough energy to knock electrons out of atoms or molecules, creating ions.

Answer 7

Ionizing radiation

Question 8

What radiation is used in dentistry?

Answer 8

X-ray radation

Question 9

has enough energy to move atoms in a molecule around or cause them to vibrate, but not enough to remove electrons from atoms.

Ex. kind of radiation are radio waves, visible light and microwaves.

Answer 9

Non-ionizing radiation

Question 10

so much energy it can knock electrons out of atoms (ionization).

can affect the atoms in living things, so it poses a health risk by damaging tissue and DNA in genes. Ionizing radiation comes from x-ray machines, cosmic particles from outer space, and radioactive elements.

Answer 10

Ionizing radiation

Question 11

What are examples of non-ionizing radiation?

Answer 11

1. Power lines
2. Radio & cell phones
3. Microwaves
4. Infraraed
5. Visable light

Question 12

Examples of ionizing radiation

Answer 12

1. UV light
2. X-ray
3. Gamma ray

Question 13

What are the 5 major types of ionizing radiation?

Answer 13

1. Alpha
2. Beta
3. Gamma rays
4. X-ray
5. Neutrons

Question 14

What rays of ionizing radaiton are the most dangerous and penatrative?

Answer 14

Neutron rays

Question 15

Two forms of radiation?

Answer 15

1. Electromagnetic (ionizing and non; pure energy no weight)
2. Particle radtiation (ionizing; tiny fast particle with mass)

Question 16

what can occur if alpha particles enter the bodu?

Particulate radiation , 2p2n

Answer 16

Damage of living tissues severe DNA damag, more dangerous than other radiation.

Question 17

travel farther in air than alpha particles but can be stopped by a layer of clothing or by a thin layer of a substance such as aluminum.

Some ____ particles can penetrate the skin and causing damage such as skin burns. but more harmful within.

Answer 17

Beta Paricles

Question 18

weightless packets of energy called photons. Can pass completely through the human body; as they pass through, they can cause ionizations that damage tissue and DNA.

Answer 18

Gamma Particles

Question 19

Pure photons of energy, emitted from a process outside of the nucleus lower in energy & less penetrating.

Answer 19

X-ray

Electromagnetic radatiion

Question 20

High speed nuclear particles, only one to make objects radioactive

Answer 20

Neutrons

particulate radiation

Question 21

What are 6 diffrent examples of electormagenetic radation?

Answer 21

1. X rays
2. Gamma rays
3. UV rays
4. Visible light
5. IR
6. Radio waves

Question 22

considers electromagnetic radiation as small discrete bundles of energy called photons, or quanta.

Answer 22

Quantum theory

Question 23

the amount of energy acquired by one electron accelerating through a potential difference of one volt.

Answer 23

Electron Volt eV

Question 24

The distanced between crest of one was and the next

Answer 24

Wavelength

Question 25

What is relationship btwn wavelength, frequency, and energy

Answer 25

Longer wave lenght= lower frequency= lower energy

Question 26

What is highest and lowest energy on electormagnetic scale?

Answer 26

* Highest energy= shortest wavlenth= gamma rays * Llowest energy= longest wavelength= radio waves

Question 27

* invisble cannot be dected by senses * no mass or weight * no charge * speed of light * short λ high freq * travel straight or displaced by objects * absorbed by matter * Can penetrate and cause ionization * Flouresce * Produce image on film

Answer 27

Propeties of X-radiation | High-energy, ionizing electromagnetic radiation.

Question 28

What are the 3 parts of the machien

Answer 28

1. Control panel 2. Extension arm 3. tube head

Question 29

What part of the machiene shoots the x-ray

Answer 29

Tube head

Question 30

is a tightly sealed, heavy metal housing that contains the x-ray tube that produces dental x-rays.

Answer 30

Tube Head

Question 31

X-rays are **electric energy in the form of_____** into the tube head

Answer 31

form or electrons

Question 32

What is the source of electrons in the the tube head? (-) electrode

Answer 32

Cathode | thermonic emmssion

Question 33

A (-) charged ____ that then reuses the electrons by directing them in a beam at the corresponding ____

Answer 33

negative cathode to postive anode

Question 34

**positive electrode**, consists of a *wafer-thin tungsten* plate embedded in a *solid copper rod*. The purpose is to** convert electrons into x-ray photons.**

Answer 34

Anode

Question 35

Smaller focal spots produce a ____ image

Answer 35

Small focal spot= sharper image

Question 36

The anode, which is composed of a highly stable material such as ____ , also serves to **dissipate some of the heat created.**

Answer 36

Tungsten

Question 37

Where are the electrons deaccelearated?

Answer 37

The Anode

Question 38

When **electrons are deaccleated int he anode** the energy is released in the form of heat and what?

Answer 38

X-ray photons | 99%

Question 39

Remves obstruction to electorns

Answer 39

Vaccume chamber

Question 40

What accelarates the electrons?

Answer 40

A high voltage feild btwn the cathode and the anode

Question 41

Cotnain stray electrons & x-rays

Answer 41

Lead sheilding

Question 42

coiled wire made of tungsten, which produces electrons when heated.

Answer 42

Tungsten filament | cathode

Question 43

which **focuses the electrons into a narrow beam** and directs the beam across the tube toward the tungsten target of the anode.

Answer 43

Molybdenum cup

Question 44

# what part on anode? serves as a focal spot and converts bombarding electrons into x-ray photons.

Answer 44

Tungsten Target

Question 45

# What part functions to dissipate the heat away from the tungsten target.

Answer 45

Copper stem

Question 46

the **penetrating x-ray beam** that is produced at the target of the anode and that exits the tubehead.

Answer 46

Primary Raditation beam | **inital x-ray to leave, straight trajectory**

Question 47

x-radiation that is created when the primary beam interacts with matter. **less penetrating**

Answer 47

Secondary Radiation beam | **x-ray hiting the person**

Question 48

form of secondary radiation and is the result of an **x-ray** that has been **deflected from its path by the interaction with matter. **

Answer 48

Scatter Radiation | **dangerous to patient & radiographer**

Question 49

What 3 things can happen to x-rays when they leave?

Answer 49

1. Photon pass through pt. **without interaction** reach receptro 2. photon **absorbed**by pt 3. photon**scattered**on to or away from the receptor

Question 50

When an **x-ray photon collides with an inner-shell electron** a ____ occurs. The photon is absorbed and ceases to exist, and a **photoelectron with a negative charge is produced.**

Answer 50

pholoelectric effect & absorbtion

Question 51

**Photon collides** with ouer shell and ejects electron, **The photon is scattered** in a different direction at a **lower energy**

Answer 51

Compton Scatter

Question 52

The **low energy ejected electron** is reffered to as a ?

Answer 52

Compton electron

Question 53

an x-ray photon is **scattered** and **no loss of energy occurs**,

Answer 53

Coherent Scatter

Question 54

produced through the photoelectric effect or Compton scatter and results in the **formation of a positive atom and a dislodged negative electron**

Answer 54

Ionization

Question 55

radiation injury suggests that **x-ray photons are absorbed within the cell** and cause the **formation of toxins, which, in turn, damage the cell.**

Answer 55

Indirect theory

Question 56

radiation injury suggests that**cell damage results when ionizing radiation directly hits critical areas**, or targets, within the cell.

Answer 56

Direct theory

Question 57

**Lethal DNA damage , cell death, decrease tissue & organ fxn**. * Xerostomia * cataracts

Answer 57

Deterministic effects | increase severtity with higher dose

Question 58

**Sub lethal DNA damage, gene mutation, replication of mutated cell** * leukemia * thyroid cancer * Cancer induction * genetic mutation

Answer 58

Stochastic effects | low dose raditation, probability of effects increses with absorbed dose

Question 59

produces poor health in the exposed animal but **does not** produce **mutations in subsequent generations**.

Answer 59

Somatic mutation

Question 60

does not affect the exposed animal but produces **mutations in future generations**.

Answer 60

Genetic mutation

Question 61

What 3 characteristic of cells that determin radaiton effect on cells?

Answer 61

1. Mitotic activity (higher worse) 2. Cell differentiation (immature cells worse) 3. cell metabolism (higher worse) | worse is more senstivte to radiaion

Question 62

* Small lymphocyte * Bone marrrow * Reproductive cells * intersitial mucosa

Answer 62

Radio **sensitive** cells | high turnover of cells

Question 63

* Muscle tissue * Nerve tissue * mature bone & cartilage * salivary gland * thyroid gland * kidney * liver

Answer 63

Radio **resistant** cells

Question 64

an organ that, if damaged, diminishes the quality of a person's life

Answer 64

Critical organ | skin, thryoid glad, lens. of eye, bone marrow

Question 65

What measure of radation is used tradiaitonally?

Answer 65

Roentgen