0:04

in a three-month-old child with tuber sclerosis complex.

0:07

We can see a large ovoid lesion in the

0:11

anterior body of the right lateral ventricle

0:14

that's predominantly hypointense on T2-weighted imaging.

0:20

It is intermediate hyperintense

0:22

on T1-weighted imaging and it demonstrates

0:25

post contrast enhancement.

0:29

In terms of other manifestations

0:30

of tuberous sclerosis complex,

0:32

T2 weighted imaging,

0:33

we're not seeing a lot, but in the first few months of life

0:37

when a patient's unmyelinated,

0:39

we don't often see it.

0:40

Notice on T1 weighted imaging,

0:42

we are seeing areas of dysplasia

0:45

in both cerebral hemispheres.

0:47

And we're not seeing any other dominant

0:51

subependymal nodules.

0:52

This patient was observed over time

0:54

and treated with an MTOR inhibitor.

0:58

That resulted in the lesion getting a little bit smaller

1:01

and having some cystic degeneration.

1:05

We can see that the central part

1:07

of the lesion is more cystic.

1:09

We have this peripheral rim of enhancing tissue.

1:13

But that, unfortunately, was still large

1:17

enough that it was worried that it would

1:20

impinge the foramen of Monroe and result

1:23

in obstructive hydrocephalus.

1:27

So, an intraoperative MRI was performed and

1:30

a surgical resection was undertaken.

1:32

So, we can see a anterior bi-parietal

1:37

craniotomy centered to the right and midline.

1:40

They took an interhemispheric approach.

1:43

They focally transected the anterior body of

1:46

the corpus callosum

1:47

and they resected the lesion.

1:50

So, the intraoperative MR shows

1:52

absence of the lesion.

1:55

This is the post contrast imaging and we're

1:58

not seeing any residual enhancing

2:00

lesion in that location.

2:01

There's a small enhancing lesion

2:03

on the contralateral side.

2:05

But this subependymal nodule is not

2:07

at risk for the impending impingement of the

2:10

foramen of Monroe and would be casually

2:12

referred to as a subependymal nodule,

2:14

and not as a subependymal giant cell astrocytoma,

2:18

several additional lesions as well.

2:21

What did this look like at post-op?

2:26

No,

2:27

this shows focal transection of the

2:29

antibody of the corpus callosum,

2:30

which was the access for the

2:32

interhemispheric approach to the subependymal

2:34

giant cell astrocytoma that was in the right lateral ventricle.

2:37

And on T2-weighted imaging,

2:40

we're seeing absence of that lesion and the

2:44

restoration of patency of the anterior

2:46

body of the right lateral ventricle.

2:48

So, this is a patient who had a subependymal giant

2:51

cell astrocytoma, with partial involution

2:54

on MTOR inhibitor therapy.

2:56

However, due to the persistent large size and the

3:02

proximity to the foramen of Monroe,

3:04

an interoperative MR was performed.

3:06

It confirmed resection of the lesion

3:08

and post-operative imaging shows

3:11

no residual or recurrent lesion.

3:13

So, one important thing to note is that

3:16

even though there was incomplete response

3:19

to the MTOR inhibitor therapy,

3:21

the fact that it resulted in some decrease

3:25

in size, made it easier to resect.

3:27

And the fact that it was cystic in the

3:30

center also made it easier to resect.

3:32

So, while the MTOR inhibitor therapy

3:34

was not able to completely obviate

3:37

the need for surgery.

3:38

The MTOR inhibitor therapy was not

3:41

completely without benefit because it

3:43

actually did facilitate the surgical resection.