Trauma radiology

Question 1

What is the radiation dose of a CTB?

Answer 1

2mSv

Question 2

What is the radiation dose of CTAP?

Answer 2

15mSv

Question 3

What is the average australian background radiation dose per year?

Answer 3

3.1mSv

Question 4

What is the radiation dose of a typical CXR?

Answer 4

0.10msV

Question 5

What is the radiation dose of Chest CT?

Answer 5

7mSv

Question 6

What is the approx radiation dose of a Whole Body CT scan WBCT?

Answer 6

Approx 30mSv, equivalent of 10 years of background radiation

Question 7

What is the difference in radiation for the mother of a pregnant woman getting a CTPA vs VQ scan

Answer 7

VQ = 2.2mSv

CTPA = 15mSv

Question 8

What are the most commonly fracture parts of the C-spine in adults

Answer 8

C2 (30%)
C7 (20%)

Question 9

What is a mnemonic for the unstable C-spine fractures?

Answer 9

Jefferson Bit Off A Hangmans Thumb

Jefferson fracture
- burst fracture of C1, usually from axial load

Bilateral face joint dislocations
- highly unstable, associated with vertebral artery injuries

Odontoid (type 2/3) fracture
- low rate of neurological compromise

Atlanto-occipital dislocation
- Rare, often die on scene

Hangmans fracture
- C2 fracture of pars interarticularis, hyperextension and distraction

Teardrop/flexion fracture
- Usually C5-6, often causes anterior cord syndrome with quadriplegia, usually axial load or deceleration

Question 10

What is the 3 column model represent and what is each column made up of?

Answer 10

Represents the stability of a spinal fracture, with more columns being affected leading to greater instability

As the columns are made up of both ligaments and bony structures, multiple ligaments being disrupted without bony injury can still lead to significant instability