0:00

Let's take a look at this case where the

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pathology was at the L5-S1 level.

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As with everything,

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we're going to start with the scout image and

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assess whether or not there's any pathology in the

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abdomen or the pelvis, and to look for scoliosis

0:14

of the lumbar spine. In this case,

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as we scroll through our T2-weighted scan, we see

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that the pathology in the degenerative category

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is limited to the L5-S1 level.

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So, I'm going to magnify to that level in each of

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these sequences, so that way we can focus

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on where the actual problem resides.

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So here we are at the L5-S1 level.

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We have the STIR image,

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we have the T1-weighted scan, and

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we have the T2-weighted scan.

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As we look at the L5-S1 level,

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we see that there is disc material which is

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extending and involving greater

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than one-half of the spinal canal in the parasagittal plane.

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So, we're going to be saying that this is either

1:07

moderate or severe in its displacement

1:11

of the thecal sac.

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So for that, we're going to look at the axial scans,

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and I'll magnify those as well,

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just to give us a little better sense of the

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abnormality. So as we scroll down to the L5-S1 level,

1:31

on the T1-weighted and T2-weighted scan,

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we see a very large soft tissue abnormality in the

1:39

epidural space, which is deforming the thecal sac.

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Now, as we assess the canal width,

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we would probably say that this is greater than

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two-thirds of the canal width in size,

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and therefore, by convention,

1:58

this would be called a large disc herniation,

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as opposed to medium size or small.

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So, let me just re-emphasize that if we take our

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little marker and we say, all right, well,

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here's the disc herniation and the

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size here is 1.1 in centimeters.

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And then we take the overall canal width,

2:20

which is 1.5 centimeters.

2:25

It's greater than two-thirds of the spinal canal

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width, and therefore would be considered a large

2:32

disc herniation. So again, the important thing,

2:35

in my opinion,

2:36

is describing what it's doing to the thecal sac

2:39

and the exiting nerve roots.

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So, if we look on the axial T2-weighted scan,

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we can see that...

2:48

we're going to emphasize this nerve root here,

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which is the nerve root that is going to

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be compressed by the disc herniation.

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And this is the S1 nerve root.

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You can see it's being pushed way back posteriorly

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and it is abnormal in location from the contralateral

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right nerve root.

3:13

So, compressing the S1 nerve root.

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Here we have the L5 nerve root

3:19

that is about to go out the L5-S1 neural foramen.

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Here we have the S1 nerve root which is...

3:26

has disc material along it.

3:30

This disc herniation, however,

3:32

probably also affects the L5 nerve root

3:36

as well, if we trace it back from the neural foramen.

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So, the report here would describe a large

3:50

disc herniation at the L5-S1.

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If we're going to talk about the protrusion

3:57

versus extrusion issue, in my eyes,

3:59

this disc abnormality is wider at the base than it is

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anywhere in its distal portion, and therefore would

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be considered a large disc protrusion, which is

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compressing both the left L5 nerve

4:13

root, as well as to a greater degree,

4:17

the left S1 nerve root within the thecal sac.