0:00

This patient presented with neck pain,

0:04

and a magnetic resonance imaging study of the cervical

0:08

spine was requested. On the T1-weighted scan,

0:11

we see that there is a bright signal-intensity lesion

0:15

which is compressing the thecal sac from an extradural

0:18

location. It's associated at the 2, 3, 4, 5, 6, C7-T1 level.

0:25

On the T2-weighted scan, the cord is displaced.

0:29

But right now, at least,

0:31

I'd say the signal intensity of the cord is within

0:33

normal limits. It's a little bit narrowed.

0:36

On the STIR image,

0:37

we see that there is suppression of the lesion.

0:41

It's darkened signal intensity as compared

0:44

to the T2 and the T1-weighted scan.

0:47

So this suggests that this lesion contains fat.

0:50

So could this be a strange lipoma?

0:53

One of the hints here is that it does seem to have a rim

0:56

of dark signal intensity. That is probably not related

1:00

to a chemical shift artifact.

1:03

It's present also on the STIR image.

1:06

On the axial scan, maybe we can get a little bit more

1:09

information about the lesion.

1:11

So here we see the abnormality in the extradural

1:15

compartment. And once again,

1:17

it has that low signal intensity rim around the lesion,

1:20

which is bright on the T1-weighted scan,

1:23

identifying this as probably an element of the

1:26

cortex of bone with bright signal intensity.

1:30

Now, we're in a location where we could

1:32

be considering a disc herniation.

1:34

But clearly, disc herniations usually

1:36

do not show fat signal intensity.

1:40

Comparing the post-gadolinium T1-weighted scan

1:43

to the pre-gadolinium T1-weighted scan,

1:46

we didn't really notice any element of enhancement.

1:50

This is post-gad to pre-gad.

1:52

And when we did a subtraction image of the two,

1:55

we weren't convinced that there was enhancement.

1:57

So we were kind of scratching our head wondering what

2:00

this could be other than a piece of bone with bone

2:04

marrow located there. So a CT scan was ordered. Here's

2:08

the CT scan showing, well, what looked like, well

2:12

corticated bone at the C7-T1 level,

2:17

and there was that lower signal intensity

2:20

centrally representing the bone marrow.

2:24

What was critical on the axial scan was the

2:27

demonstration that this does communicate with a

2:31

portion of the bone. It wasn't sitting freely,

2:33

as it looks like here,

2:35

but when you went off to the side,

2:36

it actually was arising from the superior

2:39

facet of the T1 vertebra.

2:42

And this was resected and was an osteochondroma,

2:46

a little benign bone tumor that was arising from the

2:51

superior facet of T1 and compressing the spinal cord.