Review

Question 1

Radiation is defined as:

Answer 1

energy in the form of waves sent out over a distance

Question 2

When a neutral atom gains or loses an electron, the atom is said to be:

Answer 2

ionized

Question 3

What is defined as a charged particle?

Answer 3

An ion

Question 4

Which of the following is an ionizing radiation?

Answer 4

x-ray

Question 5

X-rays are what form of ionizing radiation?

Answer 5

Electromagnetic

Question 6

X-ray wavelength is ___ proportional to frequency

Answer 6

inversely

Question 7

X-rays are considered ___: photons of many different energies

Answer 7

heterogeneous

Question 8

X-ray energies are ______ related to their wavelength.

Answer 8

inversely

Question 9

Which of the following is a characteristic of x-rays?
-capable of producing harmful effects
-capable of penetrating matter
-electrically neutral
-have no mass
-all of the above

Answer 9

all of the above

Question 10

The property of x-rays that accounts for their effect on biological systems is that they:

Answer 10

cause ionization in matter

Question 11

What is the primary beam made of?

Answer 11

Photons

Question 12

What is remnant radiation?

Answer 12

X rays that pass through the patient and interact with image receptor

Question 13

What is electromagnetic energy attenuation?

Answer 13

It is the reduction in intensity that is the result of absorption and scattering

Question 14

Energy of a photon is directly proportional to what other characteristic of a sine wave?

Answer 14

The photon’s frequency

Question 15

Which type of atom, bone or soft tissue, is more likely to have a photoelectric interaction with the incident photons? Why?

Answer 15

Bone: incident photons are more likely to be absorbed

Question 16

What do the effects of photoelectric events look like on a diagnostic image?

Answer 16

Photoelectric events correspond to a light or white shade on the image

Question 17

T/.F: Photoelectric events are important because they contribute to the contrast of our images.

Answer 17

True

Question 18

What are the most important characteristics of image quality?

Answer 18

Spatial resolution
Contrast resolution

Question 19

The ability to image similar tissue and be able to distinguish between them; variation in grayscale. Best measures the visibility of image detail

Answer 19

Contrast resolution

Question 20

Imaging small objects with high subject contrast; best measures the sharpness of image detail

Answer 20

Spatial resolution

Question 21

Spatial resolution can also be called what?

Answer 21

Image detail/Recorded detail

Question 22

If you want to get sharpness of image detail you should do what 3 things?

Answer 22

-Smallest focal spot
-Longest SID
-Anatomy as close to the IR as possible

Question 23

A random fluctuation in the OD of the image.

Answer 23

Noise

Question 24

Quantum mottle is a form of what?

Answer 24

Noise

Question 25

What is most detrimental to recorded detail?

Answer 25

Motion

Question 26

What are some ways to reduce motion blur?

Answer 26

-use shortest exposure time -provide clear instructions

Question 27

If you have increased image blur (or noise) you have reduced ___________?

Answer 27

Spatial resolution

Question 28

What type of relationship does focal spot size and focal spot blur have?

Answer 28

Direct

Question 29

As focal spot size increases what happens to recorded detail?

Answer 29

Decreases (inverse relationship)

Question 30

To produce a change of OD you must adjust which controlling factor?

Answer 30

mAs

Question 31

What does mAS control inside the x-ray tube?

Answer 31

Quantity; # of electrons boiled off of the filament

Question 32

This law states that density is proportional to the total energy imparted onto the IR.Or, as long as mAs stays the same, a change in mA or time will not effect the OD.

Answer 32

Reciprocity law

Question 33

Why is kVp a secondary or influencing factor of OD?

Answer 33

kVp = the amount of electron kinetic energy

Question 34

What is the controlling factor for radiographic contrast?

Answer 34

kVp

Question 35

Which kVp setting (high/low) will produce long scale, low contrast?

Answer 35

High kVp

Question 36

What type of distortion is magnification?

Answer 36

Size distortion

Question 37

How is size distortion (aka magnification) best reduced?

Answer 37

Increasing the SID and decreasing OID

Question 38

How does SID and OID affect recorded detail?

Answer 38

The longer the SID and the shorter the OID = sharper image detail

Question 39

Which will increase radiographic magnification more: Increasing OID or decreasing SID?

Answer 39

Increasing OID

Question 40

Improper alignment of the patient, x-ray tube and IR results in ______?

Answer 40

Shape distortion

Question 41

If there is an issue with alignment of the body part and IR, size distortion is classified as either _____ or _____.

Answer 41

Foreshortening or elongation

Question 42

What can be used to assist the radiologic technologist in limiting superimposition?

Answer 42

Oblique positions and axial projections

Question 43

Brightness in digital imaging is the equivalent of describing ________ in analog (screen film) imaging.

Answer 43

Optical density

Question 44

What is collimation? And why is collimation important?

Answer 44

The action of narrowing the x-ray beam; reduces patient radiation dose and increases image quality

Question 45

Which imaging technique factor corresponds with patient dose? 

Answer 45

mAs