0:01

When we consider epidural hematomas of the spinal canal,

0:04

far and away the most common is going

0:06

to be secondary to previous surgery.

0:08

And we're talking about in the immediate

0:10

surgical post-op scanning.

0:14

So, it is not uncommon for the neurosurgeons or

0:17

orthopedic surgeons to order a post-op scan in order to

0:21

look at their hardware. And in so doing, to also look for

0:25

epidural hematomas that may be compressing the spinal

0:29

canal. This is a patient who, as you can see,

0:32

has surgical hardware with fusion in the lower thoracic

0:37

region extending to the lumbar region.

0:39

This is part of a complete spine MRI scan.

0:43

If you notice on the T2-weighted scan to the left, you

0:48

have what looks like narrowing of the thecal sac above and

0:51

below what is a collection in the operative bed, and

0:55

this is leading to displacement of the spinal

0:57

cord anteriorly. So here's our spinal cord,

1:00

here's our collection,

1:02

here's that narrowing of the thecal sac.

1:04

And this is quite large in size.

1:06

You'll notice that it is bright on the T2-weighted

1:09

scan, and on the T1-weighted scan, it is dark.

1:13

This darker signal on the T1-weighted scan is

1:15

in part because of the patient's kyphosis,

1:18

which leads to the relevant anatomy being farther

1:22

anterior and away from the surface coil, which is placed

1:25

on the back here and therefore

1:27

you lose signal intensity.

1:29

I'm going to try to win this a little bit better.

1:31

So nonetheless,

1:32

we do are able to see that the spinal cord is being

1:35

displaced anteriorly. On the STIR image,

1:38

you see again bright signal intensity.

1:41

It's got some heterogeneity to it and you can see that

1:44

the spinal cord is being displaced anteriorly,

1:47

the thecal sac is being narrowed, and there may

1:50

even be a little area of spinal cord

1:52

high signal intensity down here at approximately

1:55

the T10-T11 level. And again, at T11-T12.

1:59

So, is this just post-op fluid?

2:02

Is this edema? Is this hematoma?

2:04

Bottom line is that it's compressing the spinal cord.

2:07

And although the signal intensity suggests that

2:11

this is more likely to be post-op edema,

2:14

being dark on T1 and bright on T2. In

2:17

the immediate post-operative setting,

2:19

a lot of times, we can't tell the difference between

2:22

hematoma and just edema. In any case,

2:25

this patient needs to be explored since there

2:27

is cord compression and cord displacement.

2:30

Normally, we would look at the signal intensity and try

2:33

to derive whether or not this was

2:35

secondary to deoxyhemoglobin.

2:38

Deoxyhemoglobin on a T1-weighted scan is dark in signal

2:41

intensity, and on T1-weighted scans would

2:44

be also dark in signal intensity.

2:47

And you can have hemorrhage within the edematous

2:50

post-operative bed. If we look on the STIR image,

2:53

seeing these darker areas anteriorly within this

2:57

collection is worrisome for this being deoxyhemoglobin

3:01

amidst a post-operative edematous collection,

3:05

and again, is worth exploring.