0:00

I want to start out with this case that others have

0:02

seen in another vignette, just as a quick intro.

0:05

And this is a patient with right-sided leg pain

0:08

and headaches, and it illustrates this high signal intensity

0:13

area that's coming out of the disc space,

0:15

or at least appears to.

0:16

But then when you look at the axial T1,

0:19

you see that it is actually communicating with the thecal sac

0:23

and I'll scroll it. So you actually see a hole.

0:26

So the very fact that A, you've got a communicating hole,

0:30

b, the fact that it's anterior to the thecal sac,

0:33

which, by the way, can be tough to see,

0:35

but usually seromas are not in front of the thecal sac.

0:39

So that's a very useful sign, and C,

0:41

you see this nerve root trying to extricate

0:44

itself through the hole.

0:46

All those things point to the fact that you are dealing

0:49

with a dural tear. So now let's take on a case,

0:53

a 50-year-old. This is going to be the goat,

0:55

the greatest of all time dural leaks.

0:58

Let's have a look at it in our 50-year-old patient.

1:01

So this poor patient has weakness in both legs bilaterally

1:06

and severe headaches and dizziness.

1:09

And although they're not described as postural,

1:11

I'll bet they are. We've got a sagittal T2,

1:14

a sagittal T1, and an axial T2.

1:18

And there is a humongous fluid collection that's under a

1:21

lot of pressure. Now, seromas can be under pressure,

1:24

but this is kind of beyond the pale.

1:28

And then we've got another finding, which is this

1:31

dissection of the collection around anteriorly in front

1:36

of and along the side of the thecal sac, right,

1:39

as it abuts the disc space.

1:41

Now, you pointed out to me earlier the history, game over,

1:44

right, severe headaches, postural headaches.

1:46

You already know it's a dural leak.

1:48

But for imagers out there,

1:50

this has proven for me to be a very useful sign.

1:53

And you just explained it to me that as

1:56

they're pulling disc material out,

1:58

if that disc material is adherent to the thecal sac,

2:01

you can tear the dura right there.

2:03

And that may explain why I see this sign so frequently,

2:05

right, meaning it's really common to get it in the root.

2:10

Now, if you get it in the distal root,

2:13

those don't generally give you as big a problem.

2:17

Some of those are a little easier to seal up.

2:19

But when you get the more approximate

2:21

ones where the root takeoff is,

2:22

the kind of shoulder of the root comes right under and

2:27

sometimes you won't see them because the sac

2:29

will go back and tampon on it temporarily.

2:32

So generally speaking, if you have a CSF leak,

2:35

you know it at the time of surgery because you see it.

2:38

But these are some of the ones that you might not

2:40

see because they're really under the sac.

2:42

And the other thing is,

2:43

if the treatment is direct suture and repair, well,

2:47

if the thing is under the sac,

2:49

how are you going to do that?

2:50

You can't. So it's a real problem.

2:52

You have to kind of tampon on it with something else.

2:55

Some gel foam or some sort of sealant.

2:57

If it's around the corner, where you can't.

2:59

See it.

3:00

The ones that are on the top of the sac that

3:02

are facing you that you can get to are one,

3:05

easier to identify when you're there and two,

3:08

repairable when you're there.

3:10

Another point about this collection is it

3:14

matches the signal intensity of CSF.

3:17

Sometimes seromas don't quite have that match.

3:20

Certainly abscesses don't and have rim enhancement.

3:22

And hematomas are easy.

3:24

You're going to have met hemoglobin staining.

3:26

It's going to depend on the timing, too.

3:28

Meaning for a seroma to look like this,

3:30

it'd have to be a really old one, right?

3:32

Sure. To get to this point.

3:34

And we're pretty soon after the operative procedure.

3:38

So this is the goat of all dural leaks.

3:42

You've seen the sign of anterior extension of that fluid

3:46

collection, which, again, I found very helpful.

3:49

The patient's clinical syndrome totally supports

3:52

the diagnosis of a dural leak.