0:01

I'd like to talk about multiple sclerosis

0:04

and the criteria that are used in America

0:07

and in Europe for diagnosing

0:10

multiple sclerosis.

0:12

It's important to emphasize that multiple

0:14

sclerosis remains a clinical diagnosis

0:16

where MR is very strong paraclinical evidence.

0:20

It's true that MR is being used greater and

0:23

greater for the diagnosis of multiple sclerosis,

0:26

but it's always in concert with the clinical

0:29

manifestations of the disease.

0:31

This is a disease which has interesting

0:34

demographics, insofar as most of the patients

0:37

are between 20 and 50 years of age.

0:40

Although, you do see 15% of patients who have

0:44

an initial diagnosis of multiple sclerosis

0:46

made after 50 years of age

0:48

and 13% under 20 years of age.

0:53

It is a diagnosis

0:55

which has some genetic predilection.

0:57

As you see,

0:58

siblings have a higher rate,

1:00

as well as children have a higher rate of multiple

1:04

sclerosis with their siblings or parents.

1:07

It also has some temperate regions,

1:10

in that the temperate climates have a higher rate

1:14

of multiple sclerosis than those at the

1:16

extremes of temperature.

1:17

And part of this has been suggested

1:21

may be related to vitamin D deficiency,

1:24

which is what some people have suggested

1:29

may show a predilection for development

1:32

of multiple sclerosis.

1:34

However, most people believe that this is an

1:36

autoimmune inflammatory condition,

1:39

as likely to have been precipitated by some viral etiology.

1:44

As we saw on the imaging,

1:46

the classic sites for multiple sclerosis

1:49

are in the periventricular location,

1:51

juxtacortical location,

1:53

brain stem and optic nerve.

1:56

In the course of a patient's life

1:59

who has multiple sclerosis,

2:02

80% of them,

2:03

80% of them have an episode of

2:06

optic neuritis where the optic

2:08

nerve is affected.

2:09

Gray matter disease,

2:11

we are now recognizing

2:12

more readily because of high-resolution imaging,

2:15

as well as high-field strength imaging.

2:17

Although, this slide says 5% in the gray matter,

2:20

that's probably now felt to

2:23

represent more like 15%.

2:25

And there's a broad differential diagnosis

2:28

that is included when one has multiple

2:30

white matter lesions in the brain.

2:32

Most commonly,

2:33

we think of the diagnoses of acute

2:36

disseminated encephalomyelitis,

2:38

Lyme disease, vasculitis, sarcoidosis,

2:41

lupus, SAE, and toxins,

2:44

as well as migraines, SAE, in other words,

2:47

Binswanger's disease.

2:49

And that's a little bit of an older age group.

2:52

So the McDonald criteria initially said that

2:55

you had to have three out of four

2:58

of the following on MRI.

3:00

Those are a gad-enhancing lesion or nine

3:02

hyperintense lesions, infratentorial,

3:04

juxtacortical,

3:05

and three or more periventricular lesions

3:08

and/or gadolinium enhancement that was greater

3:11

than three months after a

3:12

non-enhancing lesion.

3:14

These McDonald criteria were revised and the

3:17

new McDowell criteria,

3:18

which we're working under currently,

3:20

which were developed in 2011,

3:23

or approved in 2011,

3:25

define dissemination in space

3:28

as at least one T2 lesion,

3:32

in at least two of the four areas

3:35

that we've described previously,

3:37

the periventricular region,

3:38

the juxtacortical region,

3:40

infratentorial, portion of the brain,

3:43

and the spinal cord.

3:45

Dissemination in time is defined by

3:49

appearance of a new lesion on a second scan

3:51

and may not necessarily be enhancing,

3:54

or simultaneous presence of an asymptomatic

3:58

gadolinium-enhancing and non-enhancing

4:00

lesion on a single scan.

4:02

Now, I have to say that one of the caveats

4:05

or one of the confusing aspects of the McDonald

4:09

criteria is this statement

4:11

about asymptomatic,

4:13

which obviously is difficult to identify a

4:17

specific clinical symptom for a small

4:20

white matter lesion, for example,

4:21

in the parietal white matter

4:23

or frontal white matter.

4:24

So this gets some criticism,

4:26

the inclusion of this word asymptomatic.

4:29

These are the McDonald criteria that most

4:31

programs in the United States follow.

4:34

However,

4:35

in Europe, they follow a different consensus,

4:39

and this is a more recent one in 2016.

4:42

This is the MAGNIMS

4:44

or Magnetic Resonance Imaging

4:47

in Multiple Sclerosis consensus,

4:49

and they will utilize the McDonald criteria

4:54

with the following caveats.

4:55

They include optic neuritis as a separate

4:59

location for the definition of multiple

5:03

sclerosis dissemination space.

5:04

You still need two or more.

5:06

But in addition to periventricular

5:09

juxtacortical,

5:11

infratentorial and spinal cord,

5:14

they also include optic neuritis

5:16

as a fifth location.

5:18

They reclaim having greater than

5:23

three periventricular lesions.

5:25

So a single periventricular lesion,

5:28

which is appropriate for the McDonald

5:30

criteria in America,

5:32

is insufficient in the MAGNIMS consensus,

5:36

they require three or more

5:39

periventricular lesions.

5:40

They also add the cortical lesion

5:43

to the juxtacortical lesion,

5:46

which is not mentioned in

5:48

the McDonald criteria,

5:50

and they correct that issue with regard to

5:54

an asymptomatic plaque

5:55

in the dissemination time.

5:57

It need not be asymptomatic.

5:59

As long as there's a new lesion

6:00

or enhancing and non-enhancing

6:03

lesions on the same study,

6:05

you fulfill the dissemination in time

6:07

criteria for multiple sclerosis

6:10

using the MAGNIMS consensus.

6:12

And frankly,

6:13

I like this a lot better.