neuroimaging

Question 1

are structures that are more dense bright or dark

Answer 1

bright

Question 2

are structures that are less dense bright or dark

Answer 2

dark

Question 3

is fat more or less dense than water

Answer 3

fat is less dense than water

Question 4

is acute blood more or less dense than water

Answer 4

acute blood is more dense than water

Question 5

what is the most common modality for head imaging

Answer 5

CT

Question 6

normal blood number

Answer 6

40 HU

Question 7

acute blood (clotted) number

Answer 7

60-90 HU

Question 8

fat number

Answer 8

-100 HU

Question 9

what structures are found in suprasellar cistern

Answer 9

optic chiasm
pituitary gland
circle of willis

Question 10

what lobe is located in the anterior fossa

Answer 10

frontal lobe

Question 11

what lobe is located in the middle fossa

Answer 11

temporal lobe

Question 12

what lobe is located in the posterior fossa

Answer 12

cerebellum

Question 13

early sign of ischemic stroke

Answer 13

hyper dense MCA

Question 14

what can mimic hyper dense MCA sign

Answer 14

calcification

Question 15

hyper-acute phase — early

Answer 15

0-4 hours

Question 16

hyper-acute phase — late

Answer 16

4-24 hours

Question 17

acute phase

Answer 17

1-7 days

Question 18

subacute phase

Answer 18

1 week - 6 months

Question 19

when do we see fogging concept

Answer 19

subacute phase

Question 20

chronic phase

Answer 20

6 months+

Question 21

what is the most common cause of subarachnoid hemorrhage

Answer 21

aneurysm

Question 22

abnormal tissue has poor circulation so what will we see on CT with contrast

Answer 22

brighter due to delayed clearance of contrast

Question 23

what is the biggest difference between CT head with contrast and CTA

Answer 23

time

Question 24

what is the most precise method of brain imaging

Answer 24

MRI

Question 25

proton releases energy up to how many times per second depending on sequence

Answer 25

2-50+ times

Question 26

what MRI modality is good for evaluation of anatomy

Answer 26

T1

Question 27

blood vessels are easier to see on what type of MRI

Answer 27

T2

Question 28

what type of MRI best highlights inflammation

Answer 28

FLAIR

Question 29

major difference between FLAIR and T2

Answer 29

FLAIR has CSF signal cancelled periventricular lesions more visible

Question 30

DWI measures what more than anything else

Answer 30

proton movement

Question 31

DWI stands for

Answer 31

diffusion weighted imaging

Question 32

for DWI -- more movement is

Answer 32

darker

Question 33

for DWI -- less movement is

Answer 33

brighter

Question 34

on DWI, if there is decreased blood flow to an area, how will it look on imaging

Answer 34

decreased movement --> brighter

Question 35

DWI is extremely useful in

Answer 35

ischemic stroke

Question 36

DWI can measure ischemia in less than

Answer 36

less than 3 hours

Question 37

DWI should never be used without also reviewing the

Answer 37

ADC

Question 38

what does ADC stand for

Answer 38

apparent diffusion coefficient

Question 39

DWI is a calculation that is superimposed over a

Answer 39

T2 image

Question 40

does MRA require contrast?

Answer 40

no