CNS II (stroke)

Question 1

definition of stroke

Answer 1

is a clinical diagnosis where an acute neurological deficit follows a cerebrovascular insult

simply (nurological impairmnt due to vascular event) and it’s sudden and localized

Question 2

types of stroke

with % of each type

Answer 2

80% ischemic 20% hemorrhagic

Question 3

types of ischemic stroke

Answer 3

Anterior circulation infarction:
ACA infarction.
MCA infarction.
Lacunar infarction.
Posterior circulation infarction.
PCA infarction
Cerebellar infarction.
Brain stem infarction.

Question 4

types of hemorrhagic stroke

Answer 4

1. hypertensive haemorrhage.
2. Lobar haemorrhage.[CAA]
3. haemorrhagic venous infarct.
4. hemorrhagic transformation of an ischemic infarct.
5. Tumors.
6. Vascular malformation.

Question 5

Imaging modalities for stroke

Answer 5

CT
non contrast CT
MRI
less commonly, but good for identifying infarcts
CT angiography
Ultrasound/doppler

CT in the first instance

Question 6

Which is more sensitive CT or MRI

Answer 6

CT more sensitive for hemorrhagic
MRI more sensitive for infarcts

Question 7

by CT

Early signs of ischemic infarction

Answer 7

1. Dense artery sign.
2. Effacement of sulci.
3. Poor differentiation of grey-white matter.
4. Mass effect.

Question 8

mass effect in acute and chronic stroke

Answer 8

in acute stroke positive mass effect due to edema

in chronic stroke negative mass effect widened sulci and dilatation of ipsilateral ventricle

Question 9

how can you see the:
1. gray matter
2. white matter
3. CSF
by MRI

note there are three types of MRI we studied

Answer 9

T1WI
white matter = CSF = dark
T2WI
white matter = CSF = Bright
FLAIR
white matter = bright
CSF = dark

note “WI” means weighted image

Question 10

in the CT there are dense artery sign.. in the MRI ?

Answer 10

absent flow void
by T2WI

Question 11

which imaging modalities can detect ischemic infarction in the first 30 minutes

please clarify which type

Answer 11

Diffusion-Weighted Imaging, DWI

Question 12

eversibly injured brain tissue around ischemic core.. this is called

Answer 12

Penumbra

Question 13

imaging modality used to see the Penumbra

Answer 13

Perfusion-Weighted Imaging, PWI

Question 14

imaging modality can identified vascular occlusion or cause of heamorrhage

Answer 14

Digital Subtraction Angiography, DSA

Question 15

now let’s review
2 types of MRI each have specific character

Answer 15

DWI can detect ischemic infarction in first 30mins.
PWI is used to see penumbra before management to assess outcome.

Question 16

review

the most sensitive imaging modality to early recognize of ischemic stroke.

Answer 16

Diffusion weighted images DWI

Question 17

How the DWI works

Answer 17

it depends on diffusivity of hydrogen proton.

Question 18

MRI Appearance of blood according to its age:

Answer 18

1. T1 iso T2 Bright
2. T1 iso T2 Dark
3. T1 Bright T2 Dark
4. both Bright
5. both Dark

1. hyperacute < 12h
2. acute < 2 days
3. < week
4. < 2 months
5. > 2 months