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You've seen this case before in my lecture.

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It was a case of a patient with a

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sequestrated disc fragment that extended

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posterior to the thecal sac.

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So if we look in the middle panel on the

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T2-weighted scan, you can see that there

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is this soft tissue which is displacing

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the conus medullaris anteriorly and showed up

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as relatively higher signal intensity

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than the associated parent disc from

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which the herniation arose.

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And as I'll show you subsequently,

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this showed peripheral enhancement.

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The purpose of showing you this case,

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however,

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is to demonstrate the endplate changes at

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the L4-L5 and L5-S1 levels

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as they represent a nice example of what is

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termed type II endplate changes or

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modic type II endplate changes.

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On the T1-weighted scan,

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we see both at the L4-L5 level as well as at

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the L5-S1 level high signal

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intensity in the endplates on

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the T1-weighted images.

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On the T2-weighted images,

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you also see the same levels,

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the high signal intensity on T2.

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So bright on T1,

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bright on T2,

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equals type II modic changes.

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Now, as I mentioned,

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some people believe that this is related

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to fatty infiltration of the endplates

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since it's bright on the fast spin echo T2-weighted scan.

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The thing that lends some credence to this

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is if we look at the STIR image.

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So on the right hand side is our STIR

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image where fat has been suppressed.

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And as opposed to the T2-weighted scan,

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on the STIR image,

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you don't see the same level of high

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signal intensity in those endplates.

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And since STIR generally suppresses fat,

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it argues in favor

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of that theory that this represents

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fatty infiltration as opposed to

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ongoing, for example, inflammation.

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I just want to show you the post-gadolinium

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enhanced images of the patient,

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which the post-gadolinium enhanced scans

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were performed a couple

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of days after because we were confused

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as to what this might represent.

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But this is the same images that you saw

2:24

in the PowerPoint, showing the peripheral

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rim of enhancement around this free

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fragment disc material posterior to the

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thecal sac in the posterior epidural space.

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This is a fat suppressed sequence.

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And note that with respect to those

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endplate changes at L5-S1,

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this is the disk and the darker signal

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intensity is the endplate.

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You do see some suppression of the

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signal intensity, which other wise

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on a T1-weighted scan, would be bright.

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So, again, this is pre-gad and post-gad

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from the same day,

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showing that indeed there is some

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suppression of the bright signal

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intensity in the modic type II endplate

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on the post-gad scan for this patient's

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sequestrated disc fragment.