Neuroimaging (F)

Question 1

Is MRI or CT faster? 1. Which cheaper? 2. What is their relative ionizing radiation? 3. Availability? 4. Relative clinical settings? 5

Answer 1

1. CT
2. CT
3. CT has IR and MRI does not
4. CT more available
5. MRI is subacute of chronic, CT for more acute or large patients

Question 2

What is the contrast agent used in MRI? 1. What does it help in viewing? 2

Answer 2

1. Gadolinium

2. visualization of subtle lesions and well as help differentiate lesion type

Question 3

What type of device uses a rotating X-ray emitter with a ring of detectors, making many slices as it rotates and moves?

Answer 3

computed tomography (CT)

Question 4

What does Diffusion Weighted Image (DWI) MRI detect? 1. What is it good for? 2

Answer 4

1. differences in water diffusion

2. acute instances of ischemia like TIA

Question 5

What are the things that are bright in a T2 weighted MRI (pathological image)? 1. Dark? 2

Answer 5

1. fluid, fluid heavy tissue (affected areas)

2. lipid, brain tissue, bone, air

Question 6

What are the things that are bright in a Fluid Attenuated Inversion Recovery (FLAIR) MRI? 1. Dark? 2

Answer 6

1. abnormalities (good ofr pathology)

2. normal CSF fluid

Question 7

What is a MR or CT angiogram (MRA/CTA) useful for?

Answer 7

detecting vascular lesions

Question 8

What is the contrast agent used in CT? 1. What does it help in viewing? 2

Answer 8

1. iodinated contrast agent

2. aids in detection of vascular lesions and disrupted blood/brain barrier

Question 9

What are the things that are bright in a T1 weighted MRI (anatomical image)? 1. Dark? 2

Answer 9

1. fat, brain tissue

2. bone, air, fluid

Question 10

What color do denser materials appear on CT?

Answer 10

brighter (Bone=white; brain=grey, CSF=black)

Question 11

What are contraindications of using CT? 1. MRI? 2.

Answer 11

1. pregnancy, children, iodine allergies

2. implanted metallic objects, kidney issues if contrast used