0:01

On this side, we see T2-weighted scan,

0:04

T1-weighted scan, and post-gad T1-weighted scan.

0:08

Once again,

0:09

we see the low signal intensity in the endplates and

0:12

destruction of the disc. On the T2-weighted scan,

0:14

we see bright signal intensity in the disc, as well as some

0:18

extension to the endplates. On post-gadolinium enhanced scan,

0:22

you see a focal area of enhancement of the disc, as well

0:26

as irregularity of the endplates and some enhancement

0:30

of the superior endplate in the thoracic spine.

0:34

It's very important that we consider not just the discs and

0:37

the endplates, but also look at the epidural compartment.

0:42

In this case, when we look at the epidural compartment,

0:45

we see the sine qua non of an epidural lesion,

0:47

which is narrowing of the thecal sac at the level

0:51

of the pathology without cord expansion.

0:55

This patient shows a collection which is extending behind the

1:01

vertebral bodies in the anterior epidural compartment.

1:05

So this is an anterior epidural phlegmon,

1:08

which is one of the complications

1:10

of discitis/osteomyelitis.

1:12

It's an inflammatory collection that

1:14

is occurring in the epidural space.

1:17

We use the term phlegmon when we

1:19

don't see a well-defined collection,

1:22

but it's kind of more diffuse and

1:24

does not have central necrosis.

1:26

When it's a well-defined collection and has central

1:29

necrosis and a peripheral rim enhancement,

1:32

we call it an epidural abscess.

1:34

In point of fact, both of them are important because A,

1:39

they may compress the spinal cord,

1:41

but also they may lead to a phlebitis of the veins in

1:46

the anterior epidural space. When that happens,

1:49

you can get venous ischemia of the spinal cord,

1:54

leading to either cord infarction or cord damage.

1:57

So, septic phlebitis secondary to epidural collections,

2:03

infectious collections is one of the very bad complications

2:08

that can accompany discitis and osteomyelitis.

2:12

Here we have a more classic collection of an abscess.

2:17

So, as you note posteriorly at the cervical thoracic junction,

2:21

there is this collection which is epidural in location,

2:25

identified by the narrowing of the thecal sac by the collection.

2:30

In this situation, on our post-gad scan,

2:33

we see that there is rim enhancement of this collection

2:38

with central absence of the collection,

2:41

leading to a diagnosis of epidural abscess.

2:45

On the axial scans, once again,

2:47

you see the central absence of enhancement

2:53

suggesting an abscess.

2:55

And this is also seen on the T2-weighted

2:57

scan as bright signal intensity.

2:59

So, we've now seen two of the complications of discitis

3:04

and osteomyelitis. A phlegmon versus an abscess.

3:09

Here is another example of a patient who has

3:12

a thoracic epidural abscess. In this case,

3:16

we again see peripheral enhancement of the collection

3:19

with central absence of enhancement

3:22

suggesting an abscess.

3:23

In this case, showing marked compression

3:26

from posterior of the spinal cord.