0:00

Our next Case Case for write a

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history is post-op evaluation. We're going to have a poll

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question here in little this is

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actually, you know on further digging you find out it's a

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73 year old. There are three days after suffering aneurysmal silver

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rectangorage or modified Fisher grade one

0:18

hunt has great for

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They're treated with a flow diverting device across

0:23

it right internal front artery aneurysm

0:26

that ruptured.

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They're being monitored in the neurological ICU, which transcranial dopplers

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and most recently in that had

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shown Peak elevated elevated Peak velocities in

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the right middle server artery.

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So what are they thinking here post that b valve? That's not

0:43

telling us what they're concerned about. What they're concerned about is we have

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to read in between the lines. They're concerned about vasospasm and deletes Frugal.

0:49

Ischemia. So green activate the poll here. The question

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is how long after subaracterium Hemorrhage

0:56

is the peak incidence and severity of vasospasm.

1:01

That one day three days seven days 14 days

1:04

or 21 days.

1:08

This is going to be a case about the use of CT

1:11

perfusion in visual spasm and

1:14

delete cerebral. Ischemia.

1:19

So the plurality of

1:22

answers was three days, but that's not the correct answer.

1:25

The correct answer was the second most common Choice here

1:28

was seven days. So 34% of you chose seven

1:31

days, so

1:33

Visa spasm has onset around three

1:36

days peaks in incidents and severity around 70 days

1:39

and then returned back to normal after about

1:43

three weeks. In this

1:46

case. It's a just a few days after Hemorrhage. It's

1:49

at the very Leading Edge of when you can

1:52

see videos spasm and struggle. Ischemia.

1:55

So on a non-con head CT, we see the external

1:58

ventric her train. We see some scatter subarachnoid hemorrhage,

2:01

but we don't really see a great

2:04

white differentiation laws. Let's turn on our stroke windows. We

2:07

don't see well establish in part here. And

2:10

so we're gonna now turn

2:13

to our cerebral blood flow

2:17

segmentation Maps. We see nothing with segmented

2:20

in terms of CBF less than 30% and there

2:23

are some areas segmented as Team

2:26

Max career than six seconds of 28 milliliters. This is corresponding

2:29

to part of the watersheds.

2:33

That kind of ACA territories and the

2:36

medial parts of cerebral hemispheres as well as the

2:39

kind of a posterior MCA and

2:42

PCA territory here in this like Perry

2:45

atrial white matter region.

2:48

In the face of bilateral

2:51

perfusion abnormalities, I would

2:54

not rely on the CBF map segmentation

2:58

analysis by itself because

3:01

it is a relative CBF. It is comparing

3:04

to the contralateral side that is presumably

3:07

normal. But if you have bilateral abnormalities that

3:10

kind of presumption goes out the window. So let's

3:13

take a look at our color maps for CDF and

3:17

if we take this right MCA territory

3:20

to be our internal control for what

3:23

is possibly normal then relative to

3:26

that. We have some reduced

3:29

areas of cvf corresponding to the ACA

3:32

territories by lately the

3:35

PCA territories and this part of

3:38

the kind of right mcferior division

3:41

territory as well and the kind of watersheds between

3:44

the MCA and the PCA.

3:47

And we're gonna use these abnormalities kind

3:51

of inform our view of the CTA. Right?

3:54

So the term Visa spazm as

3:57

detected on CTA indicates narrowing of

4:00

the large and medium vessel, uh

4:03

arteries in the

4:06

head and we can see that the MCS are

4:09

relatively preserved maybe some mild spasm

4:12

and the emcees in terms of their caliber, you know,

4:15

the imagine your mind what they would look like normally but the

4:18

pca's are very very small the PCS are

4:21

diffusely small so very severely vasospastic

4:25

and we look A sagittal myth at

4:28

the aces. The aces are diffusely regular

4:31

very small caliber.

4:33

Sort of diffusely based as spastic and this kind

4:36

of confirms what the findings on transcranial Doppler

4:39

is but it's actually in a different territory than was

4:42

revealed by transcranial Doppler which is often unreliable. If

4:45

you're not able to get a good sonographic window into the

4:48

head and instead what we

4:51

can add in terms of value. Here are the territories

4:54

of perfusion abnormality couldn't cordant with the

4:57

territories of medium and large vessel vasospasm

5:00

that we see it really indicates

5:03

a kind of a widespread abnormality

5:06

in this case that could potentially

5:09

be symptomatic in this patient if they had,

5:12

you know, any worsening neurologic

5:15

exam.

5:16

but fortunately we did not see well

5:19

established infarct yet, but we're concerned

5:22

about it based on the areas of relatively qualitatively speaking

5:25

reduced group of blood flow on our

5:28

qualitative analysis of the CBF Maps

5:31

Okay, so

5:34

So in summary, you know with these CT images

5:37

shows there was phases spasm resulting in

5:40

some hypo perfusion in the ACA right MCA

5:43

inferior Division and related border zones.

5:48

So once again, I would I would say don't rely

5:51

too much on your CBF Maps because remembering it is a

5:54

relative comparison that they're making

5:57

the segmentation off of and we have bilateral perfusion abnormalities.

6:00

You have to fall back on your qualitative analysis of

6:03

where you think the perfusion abnormalities are compared

6:06

to relatively well preserve vascular

6:09

territories. I would also caution

6:12

you not to over read these parameter

6:15

maps that were designed for acute large

6:18

vessel occlusion Strokes. These parameters

6:21

are not well validate in the setting of vasospasm after

6:24

subarachnoid hemorrhage. It does what I

6:27

mean is that, you know, CBF less than 30 doesn't necessarily predict

6:30

reliably the development of an infarct

6:33

in that territory and team experience and six seconds is you

6:36

know, not

6:38

Validated As the metric of choice

6:41

for predicting, you know, what is critical hypoperfusion. And

6:45

and so this is still an emerging area

6:48

of practice. And so I would you know before

6:51

we have good evidence about how to interpret these findings, I would

6:54

you know, say refrain from using the same thresholds

6:57

and terminology you would use for a large vessel inclusion

7:00

stroke like core in Fark or penumbra and just state

7:03

that there are these regions of hypoperfusion. They correspond

7:06

or not to areas of vasospas and

7:09

that you can see on CTA in this

7:12

case the patient had a follow-up CT

7:15

exam several days later three days

7:18

later. So this is at Peak severity of cerebral basis spasm.

7:23

And we can see the interval development of these small

7:26

moderate size infarcts where

7:29

we saw those areas of

7:32

relatively decreased super blood flow at the

7:35

right MCA PCA border Zone here.

7:38

And kind of a cortisone between the AC and PCA

7:41

territory here as well on the right cerebral hemisphere.

7:49

Okay, so acute infarctions involving distillation territory and

7:52

mcpca Watershed territories. This patient

7:55

was taken to digital subtraction

7:58

in antiography that verified the presence

8:01

of bilateral ACA as well as PCA vasospasm and

8:04

they were treated with intrauterial Verapamil in

8:07

the base of spasm improved.

8:09

Okay, so in summary, what was this case about

8:12

this is the case of bezospasm after subarachinoid

8:15

hemorage and this starts. Typically after

8:19

three days at Peaks that when we can it resolves

8:22

after two or three weeks CTP has an

8:25

emerging role in helping diagnose. Ischemia. Ischemia. Meaning

8:28

it can be due to large vessel medium

8:31

vessel or even small vessel basic spasm rather than

8:34

just the macrovascular vases that we

8:37

necessarily see on CTA and so can be considering

8:40

an adjunct at the time that you're concerned that a subarachary

8:43

hemorrhage patient is getting worse neurologically.

8:46

Okay any questions about this case?

8:50

There is a question.

8:53

How can we know this is vasospasm or

8:56

just chronic a sterile skoretic narrowing?

9:01

Yeah, how can we distinguish bezospasm

9:04

from chronic atheroscrotic

9:07

narrowing? That's a good question. So primarily

9:10

you would want to compare to your

9:13

initial presentation CTA on

9:16

your initial presentation CT. You might have several Hemorrhage

9:19

but you probably wouldn't have visual spasm right away.

9:22

That initial CT is obtained to look for aneurysms after

9:25

you have a civil right or hammerage, right? And so they

9:28

the comparison would allow you to confidently

9:31

say this is a new abnormality and these abnormalities

9:34

are so diffuse in multiple vascular

9:37

territories and their news so

9:40

compatible with vasospasm.

9:43

What is the prognosis in Visa spasm?

9:49

Well, I think it highly depends on the degree of business

9:52

spasm and the late Superbowl.

9:55

Ischemia. So these patients with subarachary Hemorrhage can have all kinds

9:58

of neurologic sequelae developing the

10:01

weeks after the suburbage either due

10:04

to hydrocephalus or due to delay cerebral.

10:07

Ischemia. And I think

10:10

as with any other stroke highly depends on the territory involved

10:13

and the extent of that infarction.