CPS1 Imaging Revision

On an Xray and CT scan, whiter shades are ......

• more dense

• less dense

A sectional X-ray. Okay for soft tissues. Great for dense tissues.

• MRI

• X-Ray

• CT

• PET

• Ultrasonography

Part 1- A 50 year old man is involved in a RTC, he is unconscious at the scene and he is found to have multiple injuries to his head, abdomen and limbs. When he arrives in the Emergency Department the team decide he needs imaging to assess for his injuries. Which imaging modalities are they likely to use?

• MRI

• X-ray

• Ultrasound

• CT

Answer explanation

All of them! At some point he is likely to need all modalities of imaging but he is likely in the acute phase going to need CT, X-ray and USS- these all offer rapid imaging in order to see the internal trauma sustained. MRI is likely to be needed after this acute phase.

Part 2- On examination it is obvious that the patient has a head injury. He undergoes imaging to assess further. What imaging modality has been used and why? (1)

Answer explanation

Case courtesy of Dr Bruno Di Muzio, Radiopaedia.org, rID: 40731

CT scan taken as faster imaging than MRI.

CT scan -An extensive fracture of the frontal and right temporal bone with minimal displacement of the inner diploe in the frontal region (1.8 mm).

There is an associated right frontotemporal extradural haematoma that causes mass effect over the adjacent brain and midline shift.

Small foci of cerebral contusions are seen in the right frontal lobe.

A subgaleal haematoma is also present along the right frontotemporal portion of the calvaria.

What contraindications are there to plain film X-rays?

Label B indicates the ............. hemisphere

Answer explanation

Imagine you are looking at the image as if you are looking from the patients feet, this will help you to orient.

Name one relative or absolute contraindication for MRI scanning.

List 2 reasons why we use ultrasound in antenatal imaging,

Answer explanation

No radiation- safe in pregnancy.

Real time, dynamic imaging (can see blood flow, heart beat, movements, measurements of fluid and baby).

Part 1- A 75 year old woman presents with a painful LEFT wrist after a FOOSH. She has a history of an ankle fracture 2 years ago after an inversion injury and a fracture of her RIGHT wrist last year after slipping on ice. She is otherwise well and on no medication. Since her ankle fracture she has been more frail and walks with 2 sticks. Briefly explain the imaging modality used and why it was used in this case.

Part 2- The patient is diagnosed with a Colles fracture, she undergoes an operation to stabilise the fracture and subsequently visits her GP to discuss painkillers. Her GP notes she has had a number of fractures and is concerned she could have an underlying issue leading to an increased risk of fractures. What condition is the GP concerned about?

Answer explanation

Most common bone disease

Most common cause of pathological fractures

No symptoms until fractures present

Affects approximately 2% of people at 50 and almost 50% of people at 80

Mostly affect cancellous bones

Causes deterioration in the

trabecular bone matrix

Results in a reduction in bone mass