Imaging Fast Facts

Question 1

What shows up brightest on a CT?

Answer 1

Bone

Question 2

What shows up brightest on a T1W1 MRI?

Answer 2

Fat

Question 3

What shows up brightest ona T2W1 MRI?

Answer 3

CSF (fat is also still bright)

Question 4

What shows up darkest on a CT?

Answer 4

Air

Question 5

What shows up darkest on a T1W1 MRI?

Answer 5

Air, cortical bone

Question 6

What shows up darkest on a T2W1 MRI?

Answer 6

air, cortical bone

Question 7

When are neuro CTs performed with contrast?

Answer 7

Ct of head and neck looking for infection/malig
ct angiograms of head and neck
ct venograms of head and neck

Question 8

When is IV gadolinium contrast in MRI indicated?

Answer 8

infection
primary tumor/metastatic disease
demyelinating disease

Question 9

How does an acute hemorrhage look on CT?

Answer 9

hyperdense/bright white

Question 10

How does chrnoic hemorrhage appear on CT?

Answer 10

hypodense/dark

Question 11

What are the 2 most common causes of subarachnoid hemorrhage?

Answer 11

trauma

ruptured aneurism

Question 12

What is the vessel sign?

Answer 12

hyperdense (bright) vessel during a stroke

Question 13

Which MRI setting is good for looking for acute infarcts?

Answer 13

DWI (diffusion weighted imaging)

Question 14

If clinical suspicion of an acute infarct is high what imaging method do you use?

Answer 14

MRI

Question 15

What is the best for initial evaluation of spine trauma?

Answer 15

CT

Question 16

When is MRI used in the context of spine trauma?

Answer 16

to evaluate for soft tissue abnormalities such as disc, ligament, nerve, or cord injuries