0:00

Let's do our Yousemism analysis of the

0:04

L4-L5 disc on this case.

0:07

I'm showing you the sagittal STIR image

0:09

and the axial T2-weighted scan.

0:12

As we look on the sagittal T2-weighted STIR image,

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what we see is that the connection to the parent

0:19

disc is narrower than a distal portion of the disc.

0:24

So if we were to measure this using our calipers,

0:29

we would say that disc is the...

0:33

this is the width at the parent disc of 0.88,

0:36

and here is a distal portion of it, which is 1.1 cm.

0:42

So, this would be considered a disc extrusion.

0:46

And this is a disc extrusion that is better

0:48

characterized on the sagittal scan as opposed to

0:52

the axial scan. Frankly, on the axial scan,

0:55

it looks as if the base is wider here.

1:00

I suspect that the base actually is measured

1:04

from here to here. And therefore,

1:06

if we were actually to use our measuring device,

1:10

we might say that this is the width of the base,

1:13

and then it has a little bit of a neck,

1:15

and then we have a wider portion out here.

1:18

So this is a disc extrusion.

1:21

If we were to measure the overall canal width,

1:24

we would say that the canal width measures here 1.75...

1:33

I'm sorry, 1.4 cm, and the area

1:37

or the diameter that the disc is taking

1:41

up would measure from here to here, and that is 0.8.

1:48

So, 0.8 and 1.4, we would be in the moderate category.

1:53

It's not greater than two-thirds.

1:55

So, two-thirds of 1.4 is going to be over 8 mm.

2:01

So a moderate canal stenosis, secondary

2:05

to a moderate size disc herniation.

2:09

That disc herniation is an extrusion.

2:12

And that extrusion is indeed compressing the thecal

2:15

sac, as well as the nerve roots within the

2:18

thecal sac. We're at the L4-L5 level,

2:20

so we're probably dealing with the

2:22

intrathecal L5 nerve root.

2:24

There is some degenerative facet joint disease

2:28

and ligamentum flavum thickening,

2:31

but the predominant abnormality is disc disease.

2:34

So impression colon,

2:37

moderate size disc herniation,

2:39

extrusion at the L4-L5 level,

2:43

compressing the thecal sac,

2:45

as well as the intrathecal L5 nerve root.

2:51

Centrally located.