0:00

Dr. Laser,

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this is a 64-year-old woman with severe dementia

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over the course of a year.

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I have before you an axial B-value,

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about a thousand diffusion image.

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Can you summarize the imaging findings on

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diffusion before I talk about the clinical

0:18

manifestations and subtypes of CJD?

0:20

Sure.

0:20

So the first thing that you note when you look at

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this image is symmetric involvement of the deep

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gray nuclei, predominantly the caudate head,

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the putamen and the thalamus.

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Here you have a nice involvement of the medial

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aspect of the thalamus and the pulvinar.

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This would be your typical hockey stick sign.

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When you scroll up to the cortex,

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you'll notice some cortical involvement.

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You'll see this nice cortical ribbon sign.

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It just traces the gyri.

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And as you scroll down the symmetric involvement,

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essentially, all the deep midbrain structures,

0:51

one of the things that you can look for is that

0:54

this diffusion restriction actually persists

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for two weeks. It's longer than an infarct.

0:58

There's no volume loss. There's no mass effect.

1:00

And this diffusion restriction stays

1:03

within the deep gray nuclei.

1:04

Yeah. And it may stay there for like,

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a year if the patient lives that long.

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So it doesn't evolve over the course of a

1:11

week or two like a typical infarct does.

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Although, it's very infarct looking because

1:15

of the cortical involvement.

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There's even involvement back here

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in the parietal occipital region.

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And sometimes,

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if you get bilateral or bitemporal involvement,

1:23

it may simulate limbic encephalitis that occurs in

1:27

oat cell carcinoma of the lung and various

1:29

other paraneoplastic syndromes.

1:31

This patient doesn't have limbic

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system involvement.

1:34

So, let's talk a little bit about CJD and various

1:38

prion-mediated disorders.

1:40

CJD is the classic one.

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The only other one that humans get is

1:43

transmissible mink encephalopathy.

1:46

Now, most cases of CJD occur

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as a result of a sporadic mutation.

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In fact, it's 85% of CJD.

1:54

A familial gene mutation. In other words,

1:57

heredofamilial CJD, only 10%.

2:00

There are genetic causes.

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You don't have to eat meat to get this

2:04

disorder in an acquired form.

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You can get it from corneal transplant,

2:08

from tainted human growth hormone,

2:10

derived transplants.

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But getting it from a blood transfusion

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is extremely rare.

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The CJD variant,

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which is the consumption type,

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usually occurs in younger individuals,

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average age about 28

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versus the typical CJD in age 68.

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The variant, they live about 14 months,

2:31

versus the typical one,

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they live about four months.

2:34

And if you look pathologically,

2:36

they have necrosis in the brain with something

2:38

called florid daisy plaques.

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Now, let's talk a little bit about

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what you see macroscopically.

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You'll actually see a spongy brain.

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You'll see actual macroscopic and

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microscopic holes in the brain.

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Another name given to this disorder is known

2:54

as fatal familial insomnia syndrome.

2:58

And there is some debate

2:59

about what the particle consists of.

3:02

It's a proteinaceous particle.

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Some have deemed it to be infectious,

3:05

although that's somewhat in debate.

3:08

This particle has no RNA, no DNA,

3:12

and it's extremely difficult to kill.

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It's got very long incubation times,

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as much as 40 years.

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And when I say difficult to kill,

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normal sterilization doesn't eradicate the prion.

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You actually need chlorine bleach to do that.

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So that's a little bit scary.

3:29

So, in summary, classic CJD.

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Mean age, about 68,

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sporadic, shorter duration,

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usually not heredo-familial.

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Dementia, pulvinar or hockey stick sign

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may be present.

3:42

Variable amounts of protease-resistant prion protein,

3:45

or PrPres,

3:47

are present.

3:48

In variant CJD,

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younger,

3:50

mean age, 28.

3:52

You can get this from contaminated food.

3:55

Longer duration of time,

3:58

usually slower progression to death

4:00

than the classic variety.

4:01

Behavioral changes are common.

4:03

The pulvinar sign is seen in the overwhelming

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majority of patients along with the

4:07

hockey stick sign, over 75%.

4:10

So more common in variant CJD

4:13

and large amounts of protease-resistant

4:16

prion protein, PrPres.

4:19

Let's move on, shall we?

4:21

Okay. P and Laser out.