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Most of the time when we're considering

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masses in the spinal cord,

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we're in a differential diagnosis between

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astrocytoma and ependymoma. And frankly,

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there's a lot written on the distinction,

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but they often look similarly.

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So here we have a patient who has a

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large mass in the cervical spine,

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and we see that the cord is expanded with

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diminution in the width of the CSF space

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at the borders with the mass.

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And this lesion is dark on T1, bright on T2,

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as well as bright on the STIR image,

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which is typically what we see also with

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ependymomas. This case is an astrocytoma.

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An Astrocytoma, as I said,

0:45

are generally tend to be more diffuse

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in larger lesions than ependymoma.

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When we think about the differential between

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astrocytoma and ependymoma,

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we have a few things that we base our criteria on.

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Number one is that children have a higher rate

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of astrocytomas than ependymomas,

1:05

whereas adults favor the ependymoma.

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Cervical spine lesions,

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by and large, are more commonly

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astrocytomas than ependymomas,

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whereas those in the lumbosacral region,

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particularly the filum myxopapillary ependymoma,

1:23

occur in that location.

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In addition, we have that hemosiderin cap sign

1:29

that we see with ependymomas,

1:32

but that would be very rare for astrocytomas.

1:36

Both of the lesions will enhance

1:38

generally to a moderate degree.

1:41

We also saw that with neurofibromatosis type 2,

1:45

the Misme syndrome, that is multiple intracranial

1:48

schwannomas, meningiomas and spinal ependymomas,

1:52

you have ependymomas.

1:54

so neurofibromatosis type 2 is associated

1:57

with ependymoma.

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However, neurofibromatosis type 1 is associated

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with cord astrocytomas.

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So if we have the other findings of NF1,

2:08

those being the dermatologic café-au-lait spots, et cetera,

2:13

axillary freckling, as well as a bony dysplasia

2:17

indicative of neurofibromatosis type 1,

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we would favor astrocytomas.

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But this differential diagnosis is accurate at around 70% rate.

2:28

So this case where the lesion appears relatively well-defined,

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although it does have cord edema above and

2:34

below, we might have suggested ependymoma.

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However, the fact that this is a child,

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which we can see by the bone marrow signal

2:43

intensity changes, as well as in the cervical region,

2:46

would argue in favor of astrocytoma.

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If we pull down the post-gadolinium enhanced scan,

2:52

it's not really going to help us because

2:56

both lesions will show contrast enhancement

3:00

to a moderate degree.

3:02

So this is a cervical spinal cord astrocytoma in a child.