0:00

Alright, let's take a look at another one on the, uh,

0:03

wild side and IDH Wildtype glioblastoma.

0:07

In this case, in the right parietal occipital region,

0:11

we have a mass which has extensive high signal i tensal

0:15

and flare imaging with vasogenic edema.

0:17

We see the mass effect on the occipital horn

0:21

of the lateral ventricle On the left side, we see that

0:25

occipital horn on the right.

0:26

It's compressed, and not only is it compressed,

0:29

but on the post gadolinium enhanced scans, we notice

0:33

that this necrotic tumor,

0:34

which is extending from the occipital pole,

0:37

inferior occipital lobe into the parietal lobe, it extends

0:42

to the ventricular surface.

0:43

In this instance, we are seeing enhancement

0:47

of the occipital horn of the right lateral ventricle

0:50

and abnormal signal.

0:52

This is not the same CSF signal on the right

0:56

side as the left side.

0:58

So this is a penal infiltration

1:03

by this I dh wild-type glioblastoma.

1:05

As I mentioned, that's a poor prognostic sign

1:08

because once again,

1:10

they cannot remove this tumor

1:11

without entering the ventricle.

1:13

They don't want to enter the ventricle surgically

1:16

because you shed all those glioblastoma cells into the CSF

1:20

and that may lead itself to subarachnoid seeding.

1:23

And it also means that this is gonna be a lot more difficult

1:26

to cure also by radiation and, um, temozolomide therapy

1:31

because of that ventricular involvement.

1:34

So a poor prognostic sign

1:36

and a potential sign for subarachnoid seating.

1:39

This may be one of the cases where you're going to

1:42

have the clinicians sample the CSF to see where there are

1:47

neoplastic cells in the CSF and

1:50

or to do a complete spinal MRI

1:54

to see whether there's any subarachnoid speed seeding into

1:58

the cervical thoracic lumbosacral spine

2:00

where there may be drop metastases and subarachnoid seeding.

2:04

And how does this look on the a DC map?

2:08

Well, we actually, uh, did a measurement here

2:12

and that value for the

2:17

A DC was 730, which is again below

2:21

that 800 value that I've given you

2:24

as showing a high grade tumor.

2:26

This is the perfusion, again,

2:28

relative cerebral blood volume map.

2:29

Let me just have a, a brief moment about

2:33

CBF versus CBV for the assessment of a tumor's perfusion.

2:38

Suffice it to say that there are camps that are in favor

2:41

of CBF and there are camps that are in favor of CBV.

2:44

We use them interchangeably. Usually they are concurrent.

2:48

In other words, they agree with each other.

2:50

And the profusion map is also very important to the analysis

2:55

of the patient post-treatment

2:57

because post-treatment, usually

2:59

The issue is, is there tumor progression

3:02

or is there pseudo-progression

3:04

because of Temodar therapy associated with, again,

3:07

that MGMT methylation status

3:10

Or is it radiation necrosis?

3:13

Radiation necrosis

3:16

and pseudo-progression while under temozolomide therapy

3:20

both show hypoperfusion, whereas tumor

3:26

progression generally is associated with hyperperfusion,

3:31

assuming that the tumor was hyper perfused at the outset.

3:35

So you, you don't expect a hypoperfused tumor

3:40

to become hyper perfused with treatment.

3:42

But if it was hyper perfused at the outset

3:45

and then you see in

3:47

after treatment that you have a hyper perfused tumor,

3:51

you're more likely to suggest that this is tumor progression

3:55

rather than pseudoprogression, which can occur

3:58

with temor therapy or radiation necrosis,

4:01

which is usually hypoperfused.

4:03

So on this, um, CBV uh, map,

4:06

and again, it could be the CBF map, you see that,

4:10

again, don't be fooled.

4:12

The necro portion of the tumor of course is going

4:16

to be hypoperfused.

4:18

There's no perfusion in necrotic tissue.

4:22

You have to look at the periphery of the tumor.

4:25

So this is all dark. I grant you like white matter or worse.

4:30

But if we look at the periphery as in this area,

4:34

so let me get to that part, which is here.

4:39

So here's necrosis, here's necrosis,

4:42

but look at the wall of this mass

4:45

and you see the red, which is the

4:49

hyper perfuse tissue.

4:51

Again, looking down more inferiorly here,

4:53

we're going down towards the lateral ventricle.

4:56

This is the append of the ventricle.

4:59

Here is hyper perfused tissue around the necrotic area.

5:04

And as you can see, it extends to the ventricular surface

5:09

on the perfusion CBV map.

5:12

So as summary IDH wild type,

5:17

therefore glioblastoma, showing areas

5:22

of enhancement that extend to the ependymal surface

5:25

of the right lateral ventricle indicating the possibility

5:30

of future subarachnoid seeding

5:32

or current subarachnoid seeding, as well as

5:37

a poor prognostic sign from the standpoint

5:39

of surgical resection and

5:42

or treatment with radiation therapy

5:45

and temozolomide, the lesion has

5:49

a DC values less than 800, 730 in this case, concurrent

5:53

with a grade four tumor, as well as

5:56

Hyper perfused areas around the

5:59

hypoperfused necrotic area.

6:03

So this is useful to understand in the future

6:07

that this is a hyper perfused tumor, so that way

6:11

when we look at the patient

6:13

after three six months of therapy,

6:16

if we see hyper perfused tissue, we're gonna suggest that

6:21

that is residual or recurrent tumor as opposed to

6:26

pseudoprogression from Temodar or radiation necrosis.

6:30

I hope that clarifies the use

6:33

and value of imaging with respect

6:37

to the profusion maps, a DC maps,

6:40

post gadolinium enhanced scans for the evaluation

6:44

of this IDH wild type glioblastoma.