0:00

Let's take a look at a 64 year old woman who

0:04

presents with cognitive issues,

0:07

ataxia and dystonia.

0:10

First of all, what is dystonia?

0:12

Dystonia is a movement disorder which your muscles

0:15

contract involuntarily,

0:17

causing repetitive or twisting movements.

0:21

It's important to understand the distinction

0:23

between these disorders, because in this case,

0:25

we've got an axial FLAIR on the left,

0:28

a T2 fast spin echo in the middle,

0:30

and a T1 on the right.

0:32

There is putaminal loss of volume,

0:36

but there's also bilateral

0:37

putaminal hyperintensity.

0:39

And the caudate is also hyperintense,

0:42

but it's not very atrophic.

0:45

In addition, the patient doesn't have Chorea.

0:48

They do have cognitive dysfunction.

0:50

So whenever you see a caudoputaminal disorder with

0:54

cognitive dysfunction in a middle aged patient,

0:57

50, 60 years of age,

0:58

you got to think about Huntington's Chorea,

1:00

which can occur, by the way, at any age.

1:03

But the fact that you have a pretty

1:05

robust appearance, in fact,

1:06

a very robust appearance of the caudate,

1:09

both the head and the anterior body goes

1:12

very much against Huntington's Chorea.

1:15

Look at how it indents the ventricles.

1:17

Look at the T1, the gray matter indentation,

1:21

best seen right here.

1:23

So, Huntington's Chorea is out for a few reasons.

1:26

That's one,

1:27

the fact that it's dystonia rather

1:29

than Chorea is a second.

1:32

Now, what are some other considerations

1:35

when you have dystonia?

1:37

This condition can affect any part of the body,

1:40

but it's usually segmental in one part of

1:43

the body, or it can be generalized.

1:46

The muscle spasms range from mild to severe,

1:49

but must be differentiated from another condition

1:52

that you'd have to consider here,

1:53

and that is corticobasal degeneration.

1:57

It's called corticobasal degeneration

2:00

because it involves the cortex and the basal ganglia.

2:04

Let's look up at the cortex.

2:05

There is some atrophy.

2:07

It's mild, it's generalized, it's diffuse.

2:11

And there is involvement of the corpus striatum,

2:14

the caudate nucleus in the putamen,

2:16

especially atrophy of the putamen.

2:18

But what differentiates CBD (corticobasal

2:23

degeneration) from this disorder, this dystonia?

2:27

And the answer is, in CBD,

2:30

there is usually one arm or one

2:32

extremity that's affected,

2:34

and then it spreads to other extremities.

2:37

And it's not a dystonic contraction.

2:39

It's more of an apraxia,

2:41

where the patient has difficulty doing purposeful tasks.

2:45

They have the muscle strength to do it,

2:47

they just simply can't do it.

2:50

So, the differentiation between this condition and CBD

2:55

is often going to be made on clinical grounds.

2:58

What other disorders would you consider

3:00

with dystonia and disappearance?

3:03

Well, one of them is Leigh's disease,

3:05

an abnormality of pyruvate carboxylase,

3:08

an enzyme,

3:09

present exactly like this,

3:11

except the patient is 64 years of age.

3:14

It's very unusual for dystonic presentation

3:19

of Leigh's disease in an adult like this.

3:21

Usually in young juveniles and early adulthood.

3:25

So because of the age, that one is out,

3:30

what about another condition that can affect both putamena?

3:35

Well, one of them, a toxic condition,

3:38

is Wernicke's encephalopathy.

3:40

It's closely related to Leigh's disease and some of

3:43

the other disorders because they all have an

3:45

effect on metabolism and ATP and oxygenation.

3:50

Let's talk about bilateral putaminal involvement

3:55

in Wernicke's encephalopathy.

3:57

First, you should have a history

4:00

of alcoholism or some type of toxicity.

4:04

Second, you should have mammillary body atrophy.

4:08

Let's see if we do.

4:09

Let's look in the sagittal projection.

4:11

In fact,

4:11

we've got a juicy mammillary body

4:13

it's of normal size.

4:15

Third, we might have hemorrhage in the mammillary body.

4:18

We don't.

4:19

So Wernicke's encephalopathy,

4:21

which is a toxicity,

4:23

an acquired condition which, by the way,

4:25

is associated with a movement disorder,

4:28

but not dystonia,

4:29

is not going to be the diagnosis here.

4:33

What are some other causes of bilateral

4:37

corpus striatum,

4:39

caudoputaminal hyperintensity?

4:41

Well, there are a number of other toxicities

4:44

exogenous that can do it.

4:47

So you'd want to do a urine and blood screen,

4:50

but there are also a number of endogenous

4:53

toxicities that can do it.

4:55

And what is an endogenous toxicity that could do this?

5:01

And the answer is Wilson's disease.

5:04

Wilson's disease,

5:05

a disorder of copper metabolism.

5:08

And we're going to talk about Wilson's

5:09

disease in the follow-up vignette.