0:00

All right, partner, we got a problem.

0:01

Here's a 57-year-old man.

0:03

He's got low back pain radiating down to both legs.

0:07

I'm Dr. Pomeranz, neuroradiologist.

0:10

He's Dr. Schupeck, neurosurgeon,

0:12

and it's a good thing he's here.

0:14

We got trouble in River City.

0:16

On the left side, we've got a Sagittal T2,

0:19

nonfat suppressed. In the middle,

0:20

we've got an anatomy T1 weighted image.

0:22

And on the far right, the all-purpose,

0:24

fat-suppressed,

0:27

heavily water-weighted sequence

0:29

where you look for bright spots.

0:31

And there is a bright spot here anteriorly,

0:33

where there's a limbus vertebra and some

0:35

spondylosis, but that is not our issue.

0:38

So he's got bilateral lower extremity pain.

0:41

And the obvious findings are at L2, L3,

0:45

where we see a vacuum effect retrolisthesis and

0:49

this globular area of mass effect pressing

0:53

on the extradural space.

0:54

And now we just simply have to decide what it

0:57

is, where it is, how it lateralizes, etc.

1:00

So let's do that in the sagittal projection.

1:03

And it's fairly broad. Not fairly broad.

1:07

It is broad, and it has anteroposterior depth.

1:12

So I would call it a herniation protrusion type.

1:17

I wouldn't object if you called it a broad-based

1:19

herniation extrusion type with inferior

1:21

extension and retrolisthesis.

1:24

It is clearly compressing the sac and both

1:27

sets of descending roots. On either side,

1:30

we're at the L2-L3 level,

1:32

so it's probably the L3 roots that are

1:33

getting hammered, producing his pain.

1:36

And, yes, there are innumerable other findings.

1:39

So my question to you now is

1:42

how do you count this?

1:44

What would be the counting method you would use?

1:46

Because unfortunately,

1:47

the surgeon ends up going in on the wrong level.

1:49

What do you want to see from the

1:51

imager for counting? Yeah,

1:53

I think that

1:57

the most important thing that you do as an

2:00

imager is help the surgeon find the right level.

2:02

Okay. You'd think,

2:03

how could you get the wrong level?

2:05

It's not impossible.

2:06

It's very easy because you're sitting here

2:09

with an MR. What if you're in the OR?

2:12

Patient's face down, large patient,

2:15

lateral X-ray. Right. Very difficult to define.

2:18

So you have to think of yourself being in there

2:21

and how am I going to help him

2:23

get the correct level or her?

2:27

Because if there's a wrong level problem,

2:29

it is a real problem.

2:30

People lose their staff privileges for that,

2:32

and particularly if there's any possible way

2:35

that you might have helped it along.

2:37

So this is priority number one.

2:40

Okay. So there's a lot of transitional levels,

2:44

but the key is being very clear.

2:47

And usually when there is any question as to

2:50

counting, my biggest conclusion is about that.

2:54

I will say,

2:56

please refer in the body of the report to the.

2:59

Level designation.

3:00

Discussion the lowest axially imaged disc space

3:04

is designated as L5, S1, or whatever.

3:07

For the purposes of this report.

3:09

The space above this or craniad to this

3:13

basically is L4-L5 is the level of predominant

3:16

pathology. Two levels above that,

3:19

there is a wedge vertebra.

3:21

There's a couple of wedge vertebrae that you

3:23

could probably see on a lateral X-ray.

3:25

A big spur that you could

3:27

see on a lateral X-ray.

3:29

I'll point all those out and give

3:30

as many landmarks as possible.

3:32

You narrate it by the anatomy and the shape?

3:34

That's right.

3:35

Just think of yourself getting a lateral

3:37

X-ray and how do you find that level?

3:40

Put yourself in that position and it may

3:42

vary the numbering and the terminology.

3:46

Is it L6?

3:47

That doesn't matter as much as being very clear

3:51

about how you got there and how he needs

3:53

to get to the level of pathology.

3:55

Sure. Retrolisthesis at L2, L3,

3:57

or giant schmalt at stuff that you could see

4:01

on a plane film to lead him right there.

4:03

And there's no way, if he gets it wrong there,

4:05

at least you didn't have anything to do with it.

4:07

Sure. When I was younger and stupider,

4:09

I used to say something like the

4:11

SMA is seen at whatever,

4:13

but not realizing that the clinician in the OR

4:16

doesn't see the SMA. So that's ridiculous.

4:18

That's just inexperience.

4:20

So

4:22

that's the guts of this case right now.

4:25

It used to be that we actually send the X-ray to

4:28

the radiologist. That doesn't happen anymore.

4:30

You don't get the hard copy,

4:31

but they might get it electronically.

4:33

And sometimes what you get back

4:35

is number 12345 useless.

4:38

What you need is you have a clamp on a vertebra.

4:43

Is that the level?

4:45

Meaning they expect you to go dig out the MR,

4:48

look at that and say, yes,

4:50

your clamp is right there at the right level.

4:53

Okay. Because they're going to do that.

4:54

They're going to open and put a marker down.

4:56

So they expect you to make that correlation,

4:59

not give them some numbering thing.

5:00

So they have to go and get all the reports and

5:02

figure out what's five and what's

5:04

four and all that. All right?

5:05

So it's the most important thing.

5:07

Meaning if you are wrong about whether

5:09

something is a disc or a schwannoma,

5:12

they're going to be, oh, man, what a bummer.

5:15

I was expecting a disc.

5:16

But boy, if you're at the wrong level,

5:18

that is a real problem.

5:20

At least they're there at the right place.

5:22

Being at the wrong place is the

5:25

ultimate problem. Well,

5:26

let's see what happened in this case.

5:28

We have a few landmarks.

5:29

We've got a vacuum phenomenon,

5:30

we got retrolisthesis,

5:31

we got this big spur to help us along.

5:34

But apparently it didn't help them along.

5:36

So let's have a look and see what happened.

5:39

Right now. Remember, the higher up in the spine,

5:42

the easier it is to make a mistake, right.

5:44

L1 is a lot easier to see.

5:46

And actually, at surgery,

5:48

you can identify the lumbosacral interspace.

5:50

And we used to do that.

5:51

We didn't used to get X-rays when we were making

5:53

big open incisions. We'd see the sacrum,

5:56

put your finger on it.

5:57

But the higher up you go, the easier it is.

6:00

So there's these upper lumbar levels that you're

6:03

going to really need some help with because that

6:05

is really easy to be off, because remember,

6:07

lamina is going down like this.

6:09

Lamina is a big facet.

6:12

Arthropathic lamina.

6:14

It's almost all the way down at the next level.

6:16

Very easy to get messed up.

6:18

Okay,

6:18

let's move on to what happened as

6:21

a companion to this vignette.