Imaging

Question 1

How are protons arranged in an MRI?

Answer 1

Magnetic fields align all the protons in one direciton

Question 2

What happens when radiofrequency pulses are fired an an MRI?

Answer 2

Radiofrequency pulses displace the protons

Question 3

How does an MRI produce an image?

Answer 3

Dependin on the recovery time of the displaced protons (which depends on tissue density) they produce different wavelengths of gamma rays which are detected & turned into an image.

Question 4

What are the benefits of an MRI

Answer 4

extreme detail

Question 5

What are the drawbacks of MRIs?

Answer 5

slow
Expensive
Noisy/claustrophobic
Cant use on people with any metal, e.g. pacemakers, screws, plates etc

Question 6

What contrast is used to pock up vascular lesions?

Answer 6

Godolinium DTPA

Question 7

What do PET/SPECT scans show?

Answer 7

Sites of Metabolic process

Question 8

How would you scan for glucose metabolism?

Answer 8

Use a radioactively tagged glucose analogue
Produces gamma rays
Pick up with a PET/SPECT Scan

Question 9

What are the benefits of SPECT?

Answer 9

Cheaper than PET & can produce 3D images