Lecture 6 materials - radiogaph

Question 1

How are x-ray images made?

Answer 1

High-energy photons interact with tissue by absorption, transmission, and scatter

X-rays that pass through the patient interact with the detector/film to create a radiograph

Question 2

What factors affect absorption vs transmission?

Answer 2

Density & tissue thickness, atomic number

As values increase, absorption increases and leads to more opaque (white) areas

Question 3

What are the 5 radiographic opacities?

Answer 3

Gas (Lucent), Fat (2nd most lucent), Soft tissue & fluid (3rd most lucent), Mineral (2nd most opaque), metal (most opaque)

Question 4

What type of compound is used to increase contrast?

Answer 4

Barium 56

Question 5

What causes opacity?

Answer 5

Density, atomic number, object thickness

Question 6

What is summation?

Answer 6

An increase in opacity due to superimposition of structures that are not in contact

Question 7

What is border effacement?

Answer 7

When 2 structures of the same radiographic opacity are in contact and their margins can’t be distinguished

Question 8

What are roentgen signs?

Answer 8

Description of your radiographic finding

Location, Margination, Number, Opacity, Shape, Size

Question 9

What is an orthogonal view?

Answer 9

Two radiographs that take views that are 90 degrees to each other

Question 10

What is a cranial-caudal view?

Answer 10

Proximal to the tarsus/carpus

Question 11

What is a dorsopalmar/dorsoplantar view?

Answer 11

Distal to the antebrachiocarpal/tarsocrural joint

Question 12

What is a mediolateral or lateral view?

Answer 12

Image travels mediolaterally (medial view to lateral view)

Images also named for the side that is down ‘lateral’ ‘dorsal’

Question 13

What is craniocaudal view or dorsopalmar/plantar view?

Answer 13

Craniocaudal - extremities proximal to carpus

Dorsopalmar - extremities from carpus to distal

Dorsoplantar - extremities from tarsus to distal

Question 14

How to make a craniocaudal hanging radiograph

Answer 14

Marker on Lateral side

Proximal up

Question 15

How to make a lateral/oblique radiograph

Answer 15

Marker on dorsal/cranial side

Proximal up, animal facing left

Question 16

Why are oblique views important?

Answer 16

They provide angles that may be distorted otherwise (summation, border effacement)

Question 17

How to accomplish an oblique view

Answer 17

Dorsomedial to palarolateral (DMPLO)

Dorsolateral to Palmaromedial (DLPMO)

Question 18

What does DLPMO stand for?

Answer 18

Dorsomedial border to Palmarolateral border

Question 19

What bone of the carpus projects back in a radiograph? What view is this?

Answer 19

Ulnar carpal bone and accessory carpal bone DLPMO

Question 20

In what view is the first carpal bone projected back?

Answer 20

DMPLO (dorsomedial palmarolateral)

Question 21

In what view is the 2nd carpal bone and medial splint bone projected back?

Answer 21

Dorsomedial palmarolateral

Question 22

Where does the majority of bone growth occur?

Answer 22

Metaphysis

Question 23

What do growth plates look like in a radiograph?

Answer 23

Radiolucent line of cartilage that separates the metaphysis from the epiphysis

Same opacity as soft tissue, leaves an opaque scar when closed

Question 24

What is the epiphysis

Answer 24

End of long bones, present between the physis and the joint

Question 25

What is the apophysis?

Answer 25

Tertiary growth center within a bone where ligaments/tendons attach

Does not contribute to bone length (greater trochanter)

Question 26

What is cortical bone?

Answer 26

Dense lamellar bone

Question 27

Can you see periosteum and endosteum on radiographs?

Answer 27

Not unless they are diseased

Question 28

What is trabecular bone?

Answer 28

Spongy bone containing trabeculae (lacy pattern of bone deposition). Found in epiphysis of long bones, short irregulr bones, and most flat bones

Question 29

What is the medullary cavity?

Answer 29

Inside portion of diaphyseal bone, less radiopaque than cortical bone, contains bone marrow and fat

Question 30

Where is the nutrient foramen located?

Answer 30

Middle of diaphysis

Question 31

How to spot articular cartilage

Answer 31

Articular cartilage is thick in younger animals. There will be a radiolucent space in young animals

Question 32

What types of structures show up with a “soft tissue opacity”

Answer 32

Cartilage, synovium, fluid, ligaments

Question 33

Does the articulation between the Axis and the Atlas have an intervertebral disc?

Answer 33

No, articulation with the dens

Question 34

When do spinous processes become more visible on vertebrae?

Answer 34

Cervical 4

Question 35

How to spot C6 and C7 on a radiograph?

Answer 35

C6 has large transverse processes

C7 has a taller spinous process than other cervical vertebrae

Question 36

What vertebrae is the anti-clinal vertebrae?

Answer 36

T11

Question 37

WHere do articular facets begin to change shape?

Answer 37

At T10 and T11

Question 38

Which vertebrae are ribs named for?

Answer 38

The transverse process with which the articulate

Question 39

How to differentiate lumbar vertebrae?

Answer 39

Bodies are longer than thoracic vertebrae

Spinous process angled cranially

Transverse process angled cranial and ventral. These should line up on a good angled radiograph

Question 40

Where can you see diaphragm attachments?

Answer 40

L3 ad L4

Question 41

What is the radiographic marker for the sacrum?

Answer 41

Promontory

Question 42

What does the sacrum look like on a radiograph?

Answer 42

Continuous smooth arch between sacrum and ilium

Question 43

Do thoracic vertebrae have discernable accessory processes?

Answer 43

Yes, T9/T10 to T13 and the first 4 lumbar vertebrae have accessory processes