Diagnostic Imaging

Question 1

Adjacent structures can be seen in radio imaging when they have different

Answer 1

Radiodensities

Question 2

The radiodensities are:

1. ) Foreign metals
2. ) Enamel
3. ) Bone
4. ) Water density
5. ) Fat
6. ) Air

Which is the most dense and which is the least dense?

Answer 2

Most dense = foreign metals

Least dense = Air

Question 3

More radiodense structures are referred to as

Answer 3

Radio opaque

Question 4

Less radiodense structures are referred to as

Answer 4

Radiolucent

Question 5

Anything that has a different radiodensity than it’s nabor can be

Answer 5

Identified

Question 6

What are some examples of water density?

Answer 6

Muscle, connective tissue, blood, cartilage, etc

Question 7

Muscle can be distinguished from an adjacent bone, but can we distinguish ligaments from cartilage?

Answer 7

No

Question 8

A growth plate within a bone can be seen because the growth plate is

Answer 8

Cartilage

Question 9

Contrast material with high (or low) radiodensity can be placed into hollow organs to provide contrast that otherwise would not

Answer 9

Exist

Question 10

When contrast material is placed into blood vessels

Answer 10

Angiography

Question 11

When contrast material is placed into the subarachnoid space

Answer 11

Myelography

Question 12

When contrast material is placed into the kidneys

Answer 12

Pyelography

Question 13

When contrast material is placed into the digestive tract

Answer 13

Barium contrast and/or air contrast

Question 14

Because materials of higher radiodensity absorb more x-ray than do material of low radiodensity, less radiation reaches the

Answer 14

Film

Question 15

Film that is less exposed will be

Answer 15

Whiter than more exposed film

Question 16

In radiography:

1. ) High radiodensity structures appear
2. ) Low radiodensity structures appear

Answer 16

1. ) Whiter

2. ) Blacker

Question 17

In modern radiography, electronic capture of the x-ray replaces film and then a computer assigns the

Answer 17

Gray scale

Question 18

The same grey scale used for radiography can be applied to CT scans but NOT to

-because they are not dependent on radiodensity

Answer 18

MRI

Question 19

Are two dimensional images of three dimensional structures

-so ventral structures will be superimposed on dorsal structures

Answer 19

Radiographs

Question 20

A single radiograph does not allow you to determine which structure is

Answer 20

In “front” of the other

Question 21

Orientation of the patient relative to the x-ray source and the film (detector)

-named based off of which surface of patients body is closest to film

Answer 21

Projection

Question 22

Patient’s anterior side faces the film and their posterior side faces the x-ray source

Answer 22

Anterior projection (PA projection)

Question 23

The patients posterior side faces the film and the anterior side faces x-ray source

Answer 23

Posterior projection (AP projection)

Question 24

When the patients left side faces the film

Answer 24

Left lateral projection

Question 25

When the patients right side faces the film

Answer 25

Right lateral projection

Question 26

Always viewed as if you are facing the patient (i.e. patient’s right is on your left), regardless of whether it is an anterior or a posterior projection

Answer 26

Frontal projections (anterior (PA) or posterior (AP))

Question 27

It is common to take two images of the same region that are in projections that are

Answer 27

Perpendicular

Question 28

Allow you to view an image that appears to be a section through the body

Answer 28

CT (computerized tomograph) and MRI scans

Question 29

X-rays are passed through the body from multiple directions and collected by sensors in

Answer 29

CT

Question 30

These signals are then analyzed and transformed into a gray scale by a computer to provide an image of a
particular level of the

Answer 30

Body

Question 31

Uses a magnetic field and pulse radiofrequency (RF) waves

Answer 31

MRI

Question 32

After each RF pulse, the emitted energy from the body is collected and analyzed and converted into an

Answer 32

Image

Question 33

Since CT and MRI are based on different technologies, the interpretation of their gray scale is

Answer 33

Different

Question 34

In a CT, fat is usually very

Answer 34

Dark (radiotranslucent)

Question 35

In an MRI, fat is usually very

Answer 35

White (high signaling)

Question 36

Are always viewed as if you are looking up into a supine patient from the patients feet

Answer 36

Axial (cross-sectional) images

Question 37

Let’s say you are looking at two images both focused on the heart, but in one image the heart is much larger than the other. Which image has the heart closer to the film?

Answer 37

Objects closer to film = smaller

Objects further from film = larger