L23: imaging the brain

Question 1

how to image newborns brain

Answer 1

ultrasound

Question 2

why can you ultrasound newborns but not adults

Answer 2

fontanelles are transparent to sound waves

Question 3

what does X-ray show best

Answer 3

bone

Question 4

3 clinical used of X-ray

Answer 4

Skull fracture
surgery
haemorrhage

Question 5

what does a CT scan use

Answer 5

X-ray

Question 6

what is the clinical use of a CT scan

Answer 6

imaging structures associated with the brain (but not the brain itself)

Question 7

What can enhance different parts of the brain in MRI

Answer 7

different tuning

Question 8

what does MRI show well

Answer 8

soft tissue

Question 9

how does MRI work

Answer 9

external magnetic field looks at the mass charge and spin of protons

Question 10

what are the different proton environments in the brain

Answer 10

water, fat

Question 11

with T1 weighted MRI what is grey

Answer 11

grey matter

Question 12

with T1 weighted MRI what is white

Answer 12

white matter

Question 13

with T1 MRI is bone visible

Answer 13

No

Question 14

what colour are the ventricles in T1 weighted MRI

Answer 14

black

Question 15

what colour is the outside scalp in T1 MRI

Answer 15

bright white (highly vascularised)

Question 16

in T2 what colour is white matter

Answer 16

dark

Question 17

in T2 what colour is grey mater

Answer 17

light

Question 18

what colour are ventricles in T2

Answer 18

light

Question 19

what method gives you a 3D reconstruction of blood vessels

Answer 19

MRI angiography

Question 20

3 chemicals you can measure in magnetic resonance spectroscopy

Answer 20

• choline
• N-acetylaspartate
• Lactate

Question 21

what does choline measure

Answer 21

cell density/ division

Question 22

are tumours high in choline

Answer 22

yes

Question 23

what does N-acetylaspartate measure

Answer 23

normal neural function

Question 24

are tumours high in N-acetylaspartate

Answer 24

No - low in tumours

Question 25

what is lactate a product of

Answer 25

glycolysis

Question 26

why do tumours have more lactate

Answer 26

as they work anaerobically

Question 27

PET=

Answer 27

positron emission tomography

Question 28

what does an EEG measure

Answer 28

neural activity in the brain

Question 29

what disease is ECoG used for

Answer 29

epilepsy

Question 30

what does ECoG do

Answer 30

localises activity if the person is already having surgery to remove this part of brain

Question 31

what does functional MRI measure

Answer 31

blood oxygen level