0:00

Okay, this is a 75-year-old woman with the

0:04

what I call the Rocky Balboa history.

0:07

Remember what they said in Rocky, "There'll be pain."

0:11

Well, pain is all the history that we get.

0:14

Not that helpful.

0:16

However, the imaging is extremely helpful.

0:20

But before we dive into the imaging,

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I'm here with my colleague, Ben Lazar.

0:23

I just want to talk a little bit about an anatomy,

0:25

and I put up a very unattractive coronal

0:28

image just to illustrate that

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there are vessels that run intersegmentally up and down,

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and they're anastomotic,

0:37

and they protect the spine from aortic atherosclerosis.

0:41

So, if the aorta is really narrowed

0:43

or obstructed in the middle,

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you know,

0:46

these vessels can serve as a bypass.

0:49

And there are delicate connections here that are

0:53

most prominent in the thoracocervical region,

0:56

in the cervical region, up higher off the screen here,

0:59

there are major deep intersegmental vessels that include

1:03

the vertebrals and the ascending cervicals.

1:07

Now,

1:07

the anterior spinal artery is probably a highlight of

1:13

dural AVF. It's the longest artery in the body,

1:16

and it's not just a single artery.

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It's a continuous series of connected arteries.

1:22

And these are also known as radiculomegaly arteries,

1:26

formed from six to eight levels that follow roots.

1:30

So let's pull down for a moment an axial and the hairpin

1:38

turn that joins the anterior spinal artery,

1:42

which is basically an anastomosis

1:47

from multiple intersegmental vessels that

1:51

join from one foramen to the other.

1:53

So you have one group of foraminal vessels down low,

1:57

and let's say we have another level up higher,

2:00

and then another group of vessels over here,

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and they're joining along the side.

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And eventually, in the coronal projection,

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they're going to make a hairpin turn facing

2:09

you like an AP projection.

2:11

Now,

2:12

the longest artery that is contiguous in the body for the

2:18

spine is the artery of Adamkiewicz from T9 to L2.

2:23

And this is present in 90% of the population.

2:27

Now, radicular branches are small.

2:30

They're small vessels. They don't supply the spine,

2:34

but they exit with the roots at every level,

2:36

unlike radiculomegillary vessels. Now,

2:39

the radiculomegillary vessels are going to be the

2:42

ones that are responsible for the dural AVF,

2:45

where there's going to be a direct connection between

2:49

a venous structure and an arterial structure.

2:53

And it'll occur out here,

2:55

and that leads to the dilation of the.

2:59

Vessels that you'll see in a Dural AVF,

3:04

and this can occur at one or more levels.

3:09

So let's take a look at our case.

3:12

And we start out with a Sagittal T2 on the left,

3:16

and I'm going to make it a little bit brighter and a

3:19

Sagittal T1. So let's begin with a sagittal.

3:21

T2. Let's scroll it.

3:24

And I'm going to ask my colleague what is the first

3:28

thing that strikes him about this case.

3:31

So the first thing that I noticed immediately was the

3:35

CONUS medullaris and the distal thoracic spinal cord.

3:38

It's thickened.

3:41

There's abnormal signal coursing through

3:44

the thickened CONUS medullaris.

3:47

And then the other thing to note is that you see these

3:49

weird serpiginous lines coursing around the CONUS

3:53

and the distal thoracic spinal cord.

3:55

Sure.

3:55

It looks like Fluffy the Rabbit.

3:56

Right. Yeah.

3:57

Looks like somebody went in there and kind

3:58

of scuffed up the surface of the cord.

4:01

But indeed, that's not the case.

4:02

These are just simply vessels from our Dural AVF,

4:07

our direct arterial to venous fistula that has produced

4:12

venous congestion and resulted in gliosis beginning

4:16

at the CONUS and working its way north,

4:19

which is a very ominous sign.

4:21

Sometimes it can be very difficult to spot this on the T

4:25

two-weighted image because the contrast resolution isn't

4:27

good enough. Although in this case, it's easy.

4:30

The PD spur

4:34

with really fine fat suppression makes it a lot easier.

4:37

I mean, look how bright that CONUS is.

4:39

Should never look that way.

4:41

And I've seen people confuse this with an infectious

4:44

myelitis, with an infiltrative tumor, et cetera.

4:48

So you have to be really dialed in not only to this fact,

4:51

but also to these little vessels on the surface of the

4:55

cord, these peel vessels that are in the intradural space.

4:58

Now, what's misleading here is that it's a woman.

5:02

60% of these are men.

5:04

My personal experience, it's been higher than that.

5:06

And then there's another little side finding here.

5:09

Maybe she drank a lot of water, but maybe not.

5:12

Maybe she's got a neurogenic bladder.

5:15

Because these patients present with back pain,

5:18

men present with impotence,

5:20

they often have difficulty with urination, and of course,

5:24

they get ascending weakness,

5:25

and eventually they do get a sensory level.

5:29

And the bowel and bladder dysfunction is typically a more

5:33

progressive finding in terms of the disease process.

5:37

Yeah. So that means you're pretty far along,

5:39

and the odds of really getting a substantial

5:41

benefit from therapy are low.

5:43

So how would you try and localize the site,

5:47

the anastomotic site or the fistulous site?

5:50

What technique would you use or what did

5:52

you use in training? So, in fellowship,

5:54

we did a couple of different things.

5:55

We would do dynamic CTA or dynamic MRA to look.

5:59

For to kind of localize the feeder, the radicular vessel.

6:03

Before we would go in and do the angio,

6:06

typically we were successful 60,

6:09

70% of the time to give an idea, to say, hey,

6:12

it's a T nine, T ten level, T ten,

6:13

T eleven level to kind of identify that radicular vessel.

6:18

So do you like one over the other for looking

6:20

for that radiculomedullary anastomosis?

6:23

Do you like CT better or did you like MR better?

6:26

You're a neuroradiologic trained young guy,

6:31

fresh out of training,

6:33

so you really were like right in the thick of it.

6:35

What did you use? The dynamic MRA was probably the best.

6:38

You like that better? Was the best.

6:40

So use that as a roadmap to plan for your true spinal

6:43

angiogram and your therapeutic intervention.

6:46

That's super helpful, I think,

6:48

for me to hear as an old goat and for people

6:51

out in the audience to hear as well.

6:53

And it gives the clinician a starting point,

6:55

either the neurosurgeon or the interventional radiologist

6:59

starting point to start at that level to look for

7:02

the vessel. So let me ask you a question.

7:04

Let's talk about the classification of these.

7:09

The classification was developed

7:11

by Anson and Spetzler in 1992.

7:14

And let me ask you about some of the syndromic

7:18

associations. Before I do though,

7:20

let me just give a quick summary of the different types.

7:23

So the type one is the most common and these

7:27

are spinal dural, AVFs and an AVF.

7:33

Just to be clear,

7:34

and I've shown this in other vignettes is a direct

7:38

communication between an artery and a vein.

7:41

So there's the artery and here's the vein,

7:45

unlike an AVM, which is sort of the Glomus type,

7:51

where you actually have a REIT or a

7:53

tangle of vessels on both sides.

7:55

And this would be more in keeping with a type two.

7:58

And these are the two most common, the AVF, type one.

8:03

And if you have a single feeder, it's a one A.

8:06

If you have multiple feeders, it's A.

8:10

Then you've got the type two, the Glomus type,

8:12

which is found, by the way, in the cord.

8:14

So type one intradural type two, this type,

8:17

the Glomus type found in the cord.

8:20

Then you've got type three, which is rare.

8:22

It's called the juvenile metameric type and

8:25

it's found out of the cord.

8:27

In fact,

8:27

it's so extensive it's often found back here.

8:30

Disregard the color because this is just the most

8:33

convenient color right now. And then type four,

8:36

which is really rare, spinal cord perimedullary AVF.

8:42

And then you've also got nonclassified spinal epidural

8:46

AVFs, which are even rarer, and then cavernomas,

8:49

which we're going to attack separately.

8:51

These are low flow state abnormalities.

8:54

Hunt but there are some syndromic associations

8:58

and they are. Associated with the DVA.

9:01

So why don't you take me through syndromically,

9:04

what's associated with each of these types of shunting?

9:08

Sure. So typically for the type one that Dr.

9:12

Pomerance just described,

9:14

there's no syndromic features for this one.

9:18

But when you get into the type twos, threes and fours,

9:21

typically for a type two,

9:22

you're going to have associated cutaneous angiomas,

9:24

CLOVES, Sturge-Weber Rendu, Osler-Weber Syndromes are also typical associations of

9:27

a type two lesion. In terms of type three,

9:34

Cobb Syndrome is one to think about,

9:37

and then in terms of type four,

9:39

you can have a mixture of these.

9:40

So hereditary hemorrhagic telangiectasia (HHT), Cobb syndrome,

9:45

Klippel-Trenaunay syndrome, Weber syndrome.

9:46

Those are typical associations for a type four lesion.

9:50

These are good to know for the boards,

9:52

if you're taking your boards as they were on my board

9:55

exam when I took it a couple of years ago.

9:57

Yeah, and I just took the boards,

9:59

the Recredentialing about a year ago.

10:00

So it even happens to older people, too,

10:02

where you have to take an exam.

10:05

I'll make another comment, though,

10:07

about some of these rarer types.

10:10

Although type two, the Glomus type, the AVM type,

10:14

you do have to go searching.

10:15

If you're looking for Hereditary Hemorrhagic Telangiectasia (HHT),

10:18

then you want to look at the Naries.

10:21

Sometimes you'll see a little blush

10:22

in the nearries on MRI,

10:24

but you should do the visual inspection

10:26

because you're all doctors.

10:27

But you absolutely have to check the brain because they

10:30

can have all kinds of vascular abnormalities in the brain,

10:33

from shunts to telangiectasias,

10:35

from fast flow to slow flow.

10:37

So you got to do a brain.

10:39

You should probably strongly consider checking at least

10:42

two other organs to see if you have Osler-Rendu,

10:47

and that includes the lung.

10:49

If you have a vascular abnormality in the lung,

10:52

very high specificity for Osler-Rendu, and then one,

10:56

not quite as high specificity, but still pretty good.

10:59

If you have a vascular anomaly in the liver,

11:02

then odds are you have a syndromic disorder.

11:06

So probably the easiest thing to do would be to use CT.

11:09

It's quick and fast and inexpensive,

11:12

but you could also opt for MRI.

11:14

Do you have any other comments about this case

11:17

before we move on? Really severe gliosis,

11:20

probably too late to get any really

11:23

good treatment result out of this.

11:26

And as you pointed out,

11:28

these little fluffy vessels on the surface and maybe even

11:31

a little siderotic reaction on the surface is consistent

11:35

with the diagnosis of a Dural AVF in a woman.

11:39

Any other thoughts?

11:41

No.

11:42

The biggest thing to think about in this case is their

11:46

degree of symptoms, whether it's paraphasia,

11:49

parapheresis sensory deficits, and then in this case,

11:52

probably on the film edge looking at the dilated

11:55

bladder discussed with the clinician,

11:58

whether or not they do have bowel.

11:59

Or bladder incontinence or dysfunction.

12:02

One other comment, too,

12:03

before we go and we will let you go.

12:06

There's a poor correlation between the Shunt level and

12:09

the symptoms. You'd think shunt level up high.

12:12

Symptoms up high. No, that's not the case.

12:14

Let's move on, shall we?