Radiology

Question 1

what type of radiation are X-rays

properties of EM radiaiton

type of wave

Answer 1

EM - electromagnetic radiation

• no mass, charge, travels at light speed and can travel in vacuum

sine wave

Question 2

3 factors that define an EM radiation as a specific type of radiation?

What happens to another factor when you alter one factor?

Answer 2

Question 3

two types of x-rays

difference between them

Answer 3

Question 4

atomic number meaning

mass number meaning

what force holds electrons to nucleus?

what is binding energy and what increases this

Answer 4

number of protons

number of protons and neutrons

electrostatic forces

= energy required to exceed electrostatic force, bigger nucleus/closer to nucleus

Question 5

radiation: electrical fundimentals

Current:
- what is current
- what are the two types
- what is the name of the name of the process of changing between these two types
- relevance of this in an x-ray unit

voltage:
- what

transformers:
- what
- types

Answer 5

Question 6

X-rays:

• effect of divergent x-ray beam on dosage when you increase the distance from the source

Answer 6

Question 7

what are the 5 components of an x-ray tube?

Answer 7

Question 8

x-ray tube:

Glass envelope function (3)

Answer 8

Question 9

x-ray tube:

1. cathode two parts
   • For both:
2. what
3. function/how
4. benefits

Answer 9

Question 10

x-ray tube:

1. anode two parts
   • For both:
2. what
3. function/how
4. benefits

Answer 10

Question 11

x-ray tube:

tube head components (4)
- what each is and function

Answer 11

Question 12

x-ray tube: collimator

• what
• function
• benefits

Answer 12

Question 13

1. how x ray beams are produced by cathode and anode?
2. what is the focal spot and its effect if too large (specific name of effect)?
3. problems with a small focal spot and fixes for this

Answer 13

1. positive anode attracts electrons, travel from cathode picking up speed (kinetic energy) - this energy is changed into a lot of heat and few photons at target

2/3. see image

Question 14

X-ray production: two products from production:

1. process’ producing heat (2)
2. TWO ways in which x-rays are produced
   • how for each
   • what produced for each?
   • which most common
   • for rarer one: 2 ways can happen?

Answer 14

Question 15

3 ways x-rays can interact with matter

name for reduction in intensity of X-ray beam and what two interactions cause this

Answer 15

Question 16

what is the normal kV of an x-ray unit for intra oral imaging?

what is the kV a measurement of?

what happens to image quality and patient dose if increase/ decrease kV

Answer 16

Question 17

X-ray image production

1. how get an image?
2. two effects of factor allowing imaging
3. how common both are and their effect on x-ray image
4. which is worse for patient?

Answer 17

4. Compton worse for patient as photoelectron effect required for image and Compton not, also allows for more reactions to occur in dif tissues. also may increase operator dose

Question 18

What method is used to reduce scatter in tissue?

what effect does this have specifically on factors causing more scatter and effect on image and effect on patient/surroundings? (6)

Answer 18

Question 19

Difference between photoelectric/Compton effects together and continuous/characteristic radiation interactions?

Answer 19

Question 20

Effects of radiation:

1. types of particles causing tissue damage caused by radiation? (3)
2. what is biological damage dependent on? (3)
3. how causes damage? (2)
4. on DNA (2 ways)
5. how easy to repair?

Answer 20

1.2.3. see image

4. single / double stranded damage (alpha caused normally)
5. single easier / double harder = mutations = change in cell function

Question 21

Tissue radiosensitivity:

1. 2 factors relative to radiosensitivity of tissue types
2. exapmles of high, moderate and low sensitive tissues

Answer 21

1. function and rate of division (> if lesser differentiated / stem cells)
2. image

Question 22

radiation: two main effects on body (broad terms)

• factors effecting both happening and when effect seen
• what both can cause

Answer 22

Question 23

Pregnancy and radiation

1. direct dose needed to cause harm

Answer 23

Question 24

radiation: staff protection:

what are the safety rules when doing radiographs

Answer 24

1. 1.5 meters away from source at all directions
2. never be in direction of beam
3. behind solid leadlined/multiple layers of plastarboard walls

Question 25

radiation protection philosophy - 3 factors methods to reduce patient dose? (4)

Answer 25

Question 26

radiology: what is the absorbed dose measured in? what is the equivalent dose and what is it measured in

Answer 26

1. Gy (gray) 2. absorbed dose multiplied by weighting factor dependent on radiation type / tissue type? = Sieverts (Sv)

Question 27

current diagnostic reference levels for intraoral radiographs in examinations? for the different types of sensors in adults and children

Answer 27

Question 28

Digital radiographs: 1. types (2) 2. cross infection control for both 3. positives and negatives of both

Answer 28

Question 29

digital phosphor plates in digital radiology: 1. plate sizes and uses 2. how is the digital image produced?

Answer 29

Question 30

digital radiology: solid state sensors: 1. how sensor works to make an image? 2. issues with increasing pixels 3. types? (dont need to know) 4 how get digital image?

Answer 30

Question 31

digital radiology: 1. 2 formats that radiogrpahs can be stored in - difference between these two types - also what else can be stored with images - benefits to these 3. best way to view a digital radiograph (env & monitor)

Answer 31

Difference = dicom used to format and transfer to any type of viewing etc. and pacs to store and manage images and data

Question 32

Film radiology: make up of film (4) and components of main component (4) and how get image from this?

Answer 32

Question 33

stages on how to get visible image from invisible latent image in film radiology? (5) different methods to get image? (3)

Answer 33

Question 34

possible issues with developing in film radiology at 4 different stages? 1. final image 2. chemical stages 3. fixing 4. washing

Answer 34

Question 35

difference between digital and film radiology and comparison (pros of digital and cons of digital compared to film)

Answer 35

Question 36

film radiology: what is Film Speed effect of intensifying screens

Answer 36

Amount of exposure needed for image, fast = loser dose but worse image as: Larger crystals = faster but worse image

Question 37

What are the different speed films called in film radiology and what are the fastest

Answer 37

D (slowest) E and F (fastest) - F fastest but not in dental use much yet

Question 38

taking of a cephalometry radiograph: how standardised? how can be used to see soft tissues also? rule for distance between receptor and focal spot and why?

Answer 38

Question 39

CBCT radiograph - what - why not indicated for cephalometry

Answer 39

Question 40

oblique lateral radiograph - what - when indicated over intra/OPT (5) - what issues indicate this type of radiograph (4)

Answer 40

Question 41

types of OPT, how done and what used for (2)

Answer 41

90 degree = orthogonal

Question 42

the 4 planes of the face relevant in radiology?

Answer 42

Question 43

OPT radiographs What OPT stands for What are 4 possible issues you can have with an OPT image? Solution to superimposition and all of these issues? * name of issue superimposition causes * which side of focal trough gives enlargement and which for shrinking

Answer 43

Ortho-pan-TOMOGRAPHY

Question 44

OPT - positves and negatives of use - way to reduce patient dose

Answer 44

Question 45

Radiographic localisation: - what is this used for - when does it have to be used and in what for? (4) - how is it done (two types) - name of second method - what occurrence is used to our advantage - two types of second method - 5 combination of radiographs to do these - what is the new 3rd way of doing this - what is the acronym to help understanding

Answer 45

Question 46

What is the purpose of quality assessment in radiology and what factors is it in reference to (7 aspects)

Answer 46

Question 47

quality assessment in radiology: - what are the 3 checks for any receptor type - signs of damage on the 3 different types of receptor? - how often should digital receptors be checked - when acceptable or unacceptable - types of errors

Answer 47

Question 48

who are the 3 groups to be protected in radiology?

Answer 48

1. patient health 2. staff health 3. public health

Question 49

When is extra oral radiograph indicated for?

Answer 49