0:00

Well, this was a 21-year-old who had an acute

0:04

neurologic episode and was presenting to

0:08

the emergency room with new onset of

0:12

tingling in the hands,

0:14

as well as the legs.

0:16

And on the scans that we're looking at,

0:18

which are the axial FLAIR,

0:20

the axial T2-weighted,

0:21

and the axial ADC map.

0:25

When we start to scroll,

0:26

we initially look at the T2-weighted scans

0:30

through the posterior fossa,

0:32

and we see that there are areas of bright

0:34

signal intensity along the periphery of the pons,

0:38

as well as adjacent

0:39

to the fourth ventricle.

0:42

These types of peripheral

0:44

brainstem lesions are

0:47

not uncharacteristic of multiple sclerosis.

0:51

So we don't just look in the

0:52

central white matter,

0:54

but we are looking at the periphery of the

0:56

brainstem for demyelinating plaques.

0:58

Here is a periventricular lesion,

1:01

but periventricular around the fourth

1:02

ventricle rather than our typical

1:04

lateral ventricle,

1:05

and very nicely seen on the T2-weighted scan

1:08

and probably visible to most

1:11

people on the FLAIR image,

1:13

particularly if I put a lot

1:14

of yellow lines around it.

1:16

These lesions are not showing

1:18

restricted diffusion.

1:22

As we continue further superiorly,

1:26

we see on the FLAIR scan of the

1:29

supratentorial region,

1:30

multiple demyelinating plaques,

1:33

and they include those in

1:34

the periventricular zone

1:38

as well as ones that I would

1:40

call juxtacortical.

1:42

So, we have both periventricular

1:45

and juxtacortical.

1:46

Notice how well these are demonstrated

1:48

on the FLAIR scans,

1:50

whereas the T2-weighted scans,

1:53

you would see them in retrospect,

1:55

but certainly not as well demonstrated as

1:58

having a pulse sequence that has dark

2:01

signal intensity to the CSF.

2:04

Let's continue to scroll further superiorly.

2:07

Lots of demyelinating plaques.

2:09

Again, ones that we would

2:11

call periventricular,

2:13

as well as one that's fairly deep and

2:16

adjacent to the gray matter,

2:18

and therefore fulfills juxtacortical.

2:21

So we're already at the point where

2:22

we have periventricular,

2:25

we have juxtacortical,

2:26

and we have infratentorial lesions without

2:29

even looking at the spinal imaging.

2:33

So, we have fulfilled the dissemination in

2:37

space criteria as defined by

2:39

the McDonald criteria.

2:41

We are not seeing plaques that are dark in

2:46

signal intensity or periphery

2:48

on the ADC map.

2:50

So right now, we have dissemination in

2:53

space, but not dissemination in time.

2:56

I want to pull down two

2:58

more pulse sequences,

3:00

and those are the postgadolinium-enhanced

3:03

scans on your right and the susceptibility

3:05

weighted scan in the center.

3:07

Now, there is a differential diagnosis for

3:11

multiple white matter lesions.

3:13

This is a real good juxtacortical

3:15

lesion here.

3:16

So, there's a differential diagnosis that

3:19

includes things such as collagen

3:23

vascular disease,

3:25

or vasculitis, or even migraines,

3:28

or post-traumatic demyelination,

3:32

which is in the differential diagnosis.

3:35

However,

3:35

if we look at the susceptibility

3:38

weighted scan in the center,

3:40

what we see on this particular

3:43

slice is a very nice examination example

3:48

of the perivenular nature of this

3:53

patient's disease.

3:54

So even here,

3:56

at 1.5 or 3 Tesla scanning, we see the vein

4:01

and we see the area of demyelination

4:04

around the vein.

4:06

Here we are seeing very nicely,

4:10

the veins and the demyelination

4:13

around the veins.

4:15

So, this allows us to be even more specific

4:18

within our differential diagnosis to

4:20

suggest that this indeed represents

4:22

multiple sclerosis.

4:24

As we scroll through the scans,

4:28

post-gadolinium,

4:29

we do not see any enhancing plaques.

4:36

Therefore,

4:37

by McDonald criteria,

4:39

the absence of seeing

4:42

enhancing plaques or cytotoxic edema

4:46

associated with demyelinating plaques,

4:49

we have not fulfilled the criteria

4:51

of dissemination in time.

4:53

Now,

4:53

the clinicians may have a patient who has

4:56

multiple episodes of a neurologic deficit.

4:59

In this case,

4:59

it was in the emergency room

5:00

with the first deficit.

5:02

So this may not actually represent

5:05

multiple sclerosis clinically,

5:07

and we have not yet fulfilled those

5:09

criteria by McDonald criteria

5:11

for dissemination in time.

5:13

So by virtue of the MR pattern,

5:17

we would say that this is likely a

5:18

demyelinating disorder with dissemination

5:21

in space with multiple juxtacortical

5:25

periventricular and infratentorial lesions

5:27

without evidence of contrast enhancing

5:30

plaques or cytotoxic edema to suggest

5:34

dissemination in time.

5:35

Clinical correlation for fulfillment of

5:38

the McDonald criteria would be required

5:40

in this particular individual.