0:00

I'd like to take this case that we

0:02

looked at for description of the various

0:05

pulse sequences and now look at it

0:06

from the standpoint of pathology.

0:09

To start with,

0:09

I just want to talk a little bit about

0:11

templates in lumbar spine reporting.

0:15

I'm sort of a minimalist with regard

0:17

to the templates.

0:18

However, on my lumbar spine

0:22

report,

0:23

I will have some cues to looking at the

0:27

various levels of the lumbar spine.

0:29

So my report will have the description

0:32

of the technique that's used and then

0:35

we'll begin with the findings with a...

0:37

my first sentences, the images through

0:40

the conus medullaris show.

0:42

And then there will be a little bracket for me to fill in.

0:44

So, I will initially look at the

0:47

appearance of the distal thoracic spinal

0:50

cord and the conus medullaris,

0:52

which is the distal most portion of that spinal cord,

0:55

and make a statement as to whether

0:56

it has a normal appearance.

0:59

The next portion of my template goes

1:01

through each of the lumbar levels.

1:03

So it will say at the L1-L2 level bracket,

1:07

at the L2-L3 level bracket,

1:09

at the L3-L4 level bracket,

1:10

at the L4-L5 level bracket,

1:11

at the L5-S1 level bracket,

1:14

and there's nothing more other than

1:16

those brackets for me to talk about those levels.

1:19

Now, there are some groups that will,

1:21

specifically within each of the levels,

1:24

talk about, you know, the disc shows blank,

1:27

the facet joints show blank,

1:29

the ligamentum flavum

1:30

or the ligaments show blank, et cetera,

1:33

and go through the various anatomic

1:36

structures at each of the levels.

1:39

I don't do that.

1:39

I do more of a free form report.

1:43

Some people will look at it from

1:44

the standpoint of the anatomy.

1:46

The central canal shows blank,

1:48

the lateral recesses show blank,

1:50

the neural foramina show blank.

1:51

So there's different ways of approaching

1:53

the lumbar spine,

1:54

which is why I tend to go with more

1:56

of my free form approach.

1:58

The last sentence or the last portion

2:02

of my template will state

2:05

on the parasagittal images bracket.

2:09

So that's my cue to look at the foramina,

2:12

in particular on the parasagittal images.

2:15

And from there, I go into the impression.

2:17

Now, I will be describing what's

2:18

happening in the pelvis and what's

2:20

happening in the abdomen elsewhere in the reports.

2:22

But those are sort of my simple lead

2:24

ins for a templated report.

2:27

The use of templates, I think, is personal.

2:31

Some people feel constrained by templates.

2:34

Some people love having the structure

2:37

of a templated report.

2:38

I know that in our musculoskeletal section,

2:41

they are very rigidly templated

2:44

with regard to all of their extremity

2:46

joints, as well as the lumbar spine.

2:49

In our neuroradiology group at Johns Hopkins,

2:52

with the exception of one individual,

2:54

14 out of the 15 of us

2:57

do much more open ended, free text reporting.

3:02

So, whatever works for you.

3:03

As long as you're getting an accurate report,

3:06

I think it's...

3:07

you could do whatever you want to do.

3:10

So, as we look at the sagittal T2-weighted scan,

3:12

I'm going to say, well, the conus medullaris looks fine,

3:14

and the lower thoracic spinal cord looks fine.

3:17

I'm not seeing anything in there.

3:18

I'll look at the thecal sac and just have

3:21

an overall sense of what I'm going to be dealing with.

3:23

And it looks like, on this particular case,

3:26

the L4-L5 level is going to be the tightest level.

3:32

As I look at the conus medullaris,

3:34

since it's on the sagittal plane,

3:36

I will next make a statement about

3:38

the alignment of the vertebrae.

3:41

So this is where I would talk about

3:42

whether there's any spondylolisthesis ,

3:45

anterolisthesis , or retrolisthesis of one vertebral level

3:49

over the other. So looking at this,

3:52

the alignment actually doesn't look all that bad.

3:54

You can quibble about what's happening at L4-L5,

3:57

but it looks pretty good.

4:00

On the axial scans, you can see,

4:03

as per the Johns Hopkins protocol,

4:05

that these are going contiguous slices

4:08

through the lumbar spine.

4:11

If you look on the left hand side of the image,

4:13

you see where these slices are being performed,

4:16

and this is true also in the T1-weighted scan

4:19

in the exact same locations,

4:20

so you can look at them side by side.

4:23

So at this point,

4:24

I'm going to be focusing mostly on

4:26

the axial T2-weighted scans.

4:29

I've already looked at the STIR image

4:31

and reported on that focal area of high

4:35

signal intensity in the posterior aspect

4:37

of the inferior endplate of L3.

4:42

So looking at the axial scans,

4:46

once again,

4:47

if you haven't already had a template

4:51

that talks about the T11-T12,

4:54

or the other levels,

4:56

you can sort of dispense with the, you know,

4:58

lower thoracic spine shows no evidence of significant

5:01

degenerative change.

5:03

Here we are coming into the L1-L2 level,

5:07

and as you can see,

5:08

there is a portion of the disc which

5:11

is extending beyond the vertebra.

5:13

And you can note that both on the sagittal plane,

5:16

as well as in the axial plane.

5:18

So this would be a disc bulge.

5:20

Frankly, for small disc bulges that are non compressive,

5:24

I really will sort of rush by that and

5:28

not make a big commentary about that disc.

5:31

So in this case,

5:32

my terminology would be there's a non compressive

5:35

small disc bulge at the L1-L2 level.

5:38

I'll continue down to the next level.

5:43

So at the next level,

5:44

we see that there is disc space narrowing at L2-L3,

5:49

and we again have a disc bulge,

5:51

which is a little bit more eccentric to the left side.

5:54

But once again, it doesn't seem to be doing

5:56

anything to the thecal sac.

6:00

So just to mark this up a little bit,

6:01

there's a slight amount of disc

6:03

bulging here to the left side.

6:05

Here's the vertebra.

6:06

You can see that also on the sagittal scan,

6:09

that there is indeed a disc bulge.

6:12

However, my emphasis is,

6:13

what is it doing to the thecal sac?

6:15

So, the terminology that I use is

6:18

basically three different terms to

6:21

describe bulges herniations,

6:23

whether they're protrusion,

6:24

extrusion, or sequestrated fragments,

6:26

and that is non compressive,

6:30

abutting and compressing, or displacing.

6:34

So, if I see that there is a disc bulge

6:38

which is up against but not displacing

6:44

a nerve root,

6:45

I call that disc abutting the nerve root.

6:49

That means that it hasn't been displaced

6:51

from its natural position.

6:54

So non compressive is not doing anything,

6:57

abutting, it's up against, displacing or compressing.

7:02

Three different levels of severity, if you will.

7:06

The point that I make with discussing this with our fellows,

7:11

is that when a patient has low back pain and they're

7:15

sent home for conservative treatment,

7:18

they're told to undergo bedrest in the,

7:22

generally, supine position.

7:25

That's supposed to be their most pain free position.

7:29

That's also the position that we

7:32

put people into the magnet.

7:35

So they are not weight loading.

7:38

They're in the position that hopefully

7:40

is their most comfortable in the magnet.

7:43

My sense is that a disc herniation or

7:48

bulge that is abutting a nerve root

7:51

could be symptomatic in the

7:54

weight loaded position.

7:56

So if that same patient was upright with

7:59

their full weight of their spine and body,

8:03

that abutment could in fact lead to nerve root irritation.

8:11

Whereas a non compressive disc herniation

8:14

that's not doing anything,

8:16

is unlikely to cause that.

8:20

So that's the patient clinical

8:23

distinction I talk about with abutting the nerve root,

8:25

versus one that's already

8:27

displacing the nerve root in the supine position,

8:31

I think is more likely to be symptomatic.

8:33

And the neurosurgeons understand this as well.

8:37

Okay, so here we have a non compressive disc

8:40

bulge and we'll continue

8:43

on to the next level.

8:45

Suffice it to say that I'm also looking

8:47

at the same time at the facet joints and

8:51

ligamentum flavum, and looking for

8:54

synovial cyst or other pathology that

8:56

may be involving the thecal sac or nerve roots

8:59

besides the disc disease. But right now,

9:02

we're emphasizing the disc disease.

9:04

So here, as you can see, when we slice...

9:07

one slice below,

9:09

we do see that this disc bulge is

9:12

indenting the thecal sac.

9:13

Here, it looked pretty good.

9:14

Here, it's indenting the thecal sac.

9:16

Here, it's abutting on the intrathecal

9:20

L4 nerve roots, or at the L...

9:22

I'm sorry, L3 nerve root.

9:24

We're at the L2-L3 level,

9:25

so this is going to be the intrathecal L3 nerve root.

9:28

So I'll say this is a disc bulge that is

9:30

abutting on the intrathecal L3 nerve root.

9:32

It hasn't displaced it from its natural position.

9:35

There is some ligamentum flavum

9:38

thickening on the left side.

9:41

With regard to ligamentum flavum,

9:43

people use the term thickening versus

9:46

hypertrophy. And the purists say, well,

9:49

those cells aren't really hypertrophied

9:52

enlarged cells,

9:53

so I just use the term thickening.

9:57

Let's continue downward,

9:58

and we are now at the L3-L4 level.

10:00

At the L3-L4 level,

10:02

we again see a disc bulge.

10:04

It is not displacing the nerve roots.

10:06

Again, we have the disc bulge which is abutting

10:09

the nerve root without displacing it.

10:10

This may or may not be symptomatic.

10:13

We again see thickening of

10:15

the ligamentum flavum,

10:16

and we see mild degenerative changes in the facet joints.

10:21

We'll continue downward from there.

10:24

And here we have something different.

10:26

So now we're at the L4-L5 level.

10:29

And even in this level,

10:32

we are sort of losing some of the

10:34

contrast that we normally have with the

10:35

thecal sac and the disc material.

10:39

So what we see is this soft tissue which

10:42

is extending all the way around here,

10:46

and it is compressing the thecal sac as

10:52

well as the intrathecal nerve roots.

10:55

And this disc material abuts on the ligamentum flavum.

11:01

Within the ligamentum flavum,

11:03

we are seeing something which is

11:05

bright in signal intensity,

11:08

which is associated with a bright

11:10

and degenerated facet joint.

11:13

This is a synovial cyst.

11:15

I'll be talking about synovial cysts

11:17

at another portion of the discussion

11:21

on degenerative disc disease,

11:22

but it is a phenomenon that is

11:25

associated with degenerative facet joint disease,

11:28

and it may be the source of the

11:31

patient's symptoms as well.

11:34

So we're going to describe this disc herniation.

11:36

We're going to describe the location of it,

11:38

and we'll talk about that momentarily,

11:40

as well as the extent at which it's

11:43

compressing the intrathecal nerve roots,

11:45

as well as the nerve root

11:46

in the neural foramen.

11:50

So here you can see the lateral recess.

11:53

Again,

11:53

we identify the lateral recess as being

11:57

at the level of the pedicles.

11:59

And this is the normal lateral recess on the left side.

12:02

Here we have a large disc fragment

12:04

which is in the lateral recess.

12:06

The lateral recess is the location for

12:08

the descending nerve root from this side.

12:09

So if we're at L4-L5, we're talking about

12:09

the L5 nerve root in the lateral

12:14

recess before it gets to the neural foramen.

12:18

And we have this big disc fragment in

12:21

that location, which is going to be

12:23

compressing the L5 nerve root in the lateral recess.

12:29

And here you can see a portion of that disc fragment.

12:32

When you see this out laterally here,

12:34

you want to look and confirm on your

12:36

sagittal scan as well.

12:38

So as we go out to the left and right side,

12:42

you can see this disc fragment

12:44

which is extending on the sagittal scan

12:47

from the L4-L5 level downward,

12:50

even into the neural foramen.

12:56

At the L5-S1 level, we have a

12:58

central disc herniation which is

13:01

compressing the thecal sac and slightly

13:03

displacing the intrathecal S1 nerve root

13:06

posteriorly on the right side

13:08

compared to the more natural position

13:09

of that nerve root on the left side.

13:18

So disc pathology here as well as a

13:21

synovial cyst associated with the L4-L5

13:26

level.

13:28

On the sagittal scan, you will see the

13:30

synovial cyst posteriorly associated

13:33

with the facet joint.

13:34

Let's see how it looks on the T2-weighted imaging.

13:38

So here is the bright signal intensity

13:40

of that synovial cyst, combined with a

13:43

large disc herniation to the right of

13:46

midline and causing compression of the

13:49

right intrathecal L5 nerve root as

13:53

well as extending to involve the

13:55

pheromonal right L4 nerve root.