Radiology Flashcards

1
Q

Why is the use of radiology to visualise body parts, tissues and organs useful for?

A

Clinical diagnosis
Treatment planning
Disease monitoring
Image guided intervention

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a Plain Radiograph?

A

The image produced by the passage of x-rays through an object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How is a Plain Radiograph produced?

A

X-rays generated and projected towards the detector with the patient positioned in between

When X-rays hit the detector plate it turns black

X-rays are absorbed/attenuated most by the dense materials in a patient like bone and any metals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 4 main densities?
From most dense to least dense:

A

Bone
Soft tissue
Fat
Air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the advantages of Radiographs/X-rays?

A

Are quick
Readily available
Cheap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the disadvantages of Radiographs/X-rays?

A

Ionising radiation
Poor soft tissue contrast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are Radiographs useful for?

A

Imaging of skeletal trauma (Fractures or Joint dislocations)

Evaluating chronic bone or joint pathologies (osteoarthritis, rheumatoid arthritis, chronic osteomyelitis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is articular cartilage?

A

The hyaline cartilage found at the ends of bones where joints are found

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

On an x-ray, why does articular cartilage of joints appear black/dark?

A

Its less dense then bone so its more radiolucent
The darkness makes it look like there’s a joint space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is a fracture?

A

A complete or incomplete break in the continuity of the bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How do fractures appear on radiographs/X-rays?

A

Fracture ones/lucent dark lines on the radiograph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 6 types of fracture?

A

-Transverse
-Linear
-Oblique
-Spiral
-Greenstick
-Comminuted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a transverse fracture?

A

Fracture which is horizontal/perpendicular to the bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a linear fracture?

A

Fracture which runs straight down the length of the bone/parallel to the bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is an Oblique fracture?

A

Fracture that happens at an angle/diagonal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a spiral fracture?

A

Fracture where the fracture line wraps around the bone in a spiral motion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a Greenstick fracture?

A

Fracture where one side of the bone will snap but the other side of the bone is fin

Medullary cavity broken but cortical bone is in tact

18
Q

What is a comminuted fracture?

A

Fracture where there is multiple breaks in the bone

19
Q

How do the bones develop in childhood?

A

Start as cartilaginous model/template
Calcification begins as Chondrocytes begin to oldie
Perichondrium develops into periosteum
Osteoclasts begin to resorb the bone in the medullary region forming the medullary cavity where the bone marrow can form
This leaves cartilage remaining only at the ends of the bone

20
Q

Describe the structure of a long bone:

A

The epiphysis is the ends of the bone past the epiphyseal plate
Articular cartilage is found at the ends of long bones
The epiphyseal plate is a region of cartilage where bone growth occurs
Diaphysis is the shaft of the long bone
Metaphysics is the region between where the bone starts to widen and the epiphyseal plate

21
Q

How do bones visibly change on a radiograph during childhood?

A

Begin to become whiter from the middle of the cartilaginous model as it calcifies to bone
Ends of bone remain dark with cartilage

22
Q

What is a displaced fracture?

A

When the fractured bone is no linger aligned

23
Q

What is an undisplaced fracture?

A

Fracture where the bone is still aligned

24
Q

What are the 3 general stages to fracture healing?

A

1.) Inflammatory phase
2.) Reparative phase
3.) Remodelling phase

25
Q

What happens in the inflammatory phase of the fracture healing process? (hours to days)

A

Haemotoma forms (blood clot)
Tissue dies
Inflammation/cell proliferation begins

26
Q

What happens in the reparative phase of fracture healing? (days to weeks)

A

Angiogenesis (formation of new blood vessels)
procallus forms
Soft callous forms and is visible
Hard callus forms

27
Q

What happens in the remodelling phase of fracture repair? (months to years)

A

The bone is remodelled by osteoblasts so that the fracture lie becomes completely obscured

28
Q

What is CT, what radiation does it use and how does it form an image?

A

Computerised tomography
X-rays

X-rays emitted from a detector that spins round in a circle very quickly, these are picked up by detectors producing many transverse images that are complied together to make a 3D image

29
Q

What are the advantages of CT scans?

A

Soft tissue detail better than plain radiographs/x-rays
Quick to do
Fractures seen much better in CT than plain radiographs
Can produce 3D images

30
Q

What are the disadvantages of CT scanning?

A

Ionising radiation (higher than plain radiograph)
Motion artefacts if patient moves
Poor soft tissue detail compared to MRI but better than x-rays

31
Q

What is the units used to state the density of body tissues?

A

Hounsfield Units (HU)

32
Q

What colour does a structure with a very low HU appear and what about a structure with a high HU?

A

Very low is Black/dark
Very high is white

33
Q

What is CT windowing?

A

When the CT image is manipulated so certain structures are highlighted

34
Q

What is MRI and how does it worK?

A

Magnetic Resonance Imaging

Magnetic field causes H+ to align
Radio pulse unaligned the H+
Radio pulse is then turned off and the time that it’s takes for the H+ to realign is measured and is used to form a cross sectional image

35
Q

What is MRI useful for imaging?

A

Bones, joins, ligaments and tendons is MSK

MRI is better than CT and x-rays in assessment of soft tissue

36
Q

What are the advantages of MRI scranning?

A

Good for soft tissue structures
Detailed anatomy of joints
Excellent for bone marrow imaging

37
Q

What are the disadvantages of MRI scanning?

A

Scan takes a long time and patients have to be still
Noisy
Claustrophobic patients can’t tolerate
Cant have patients with metallic or electronic devices like pacemakers

38
Q

What are the advantages of Ultrasound imaging?

A

No ionising radiation
Excellent soft tissue resolution
Can see fluid collections and superficial foreign bodies
Dynamic imaging
Good for image guided MSK intervention

39
Q

What are the disadvantages for Ultrasound imaging?

A

Operator dependant
Poor deep tissue
Limited bone and Intra articular imaging

40
Q

What is nuclear medicine?

A

When parts of the body are radioisotope labelled
Biologically active drugs are given to the patient to serve as a marker of biological activity

41
Q

What areas are usually viewed with nuclear medicine?

A

Bone forming metastatic lesions
Healing fractures
Areas of osteomyelitis

42
Q

How do T1 weighted images differ to T2 weighted images?

A

T1 fat appears bright and fluid dark
T2 fat bright and fluid bright