Radiology

Question 1

Describe the attenuation of bones and lungs on CT

Answer 1

Bone → High Attenuation → White

Soft tissues → Intermediate attenuation → Shades of grey

Lungs → Low Attenuation → Black

Question 2

In which way is CXR better than CT?

How is CT better than CXR

Answer 2

Spatial resolution is a lot better on CXR than CT

But contrast is better in CT as is anatomical superimposition

Question 3

Dose from a chest x-ray

Answer 3

Chest x-ray 0.014

CT head is 100X a chest x-ray

CT chest is 470X a chest x-ray

CT whole spine is 715X a chest x-ray

Question 4

How is consolidation defined

Answer 4

Increasing density which obscures the view of the bronchial and vascular markings

A bit of lung without air in it

Question 5

Causes of consolidation

Answer 5

Infection / Inflammation
Tumour (lung cancer, lymphoma)
Blood

Question 6

What is ground glass opacification

Answer 6

The air has been partially displaced from the lung

It can be airspace disease, interstitial disease, or a mixture of 2