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This is a 62-year-old man who presents with

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behavioral changes and has already progressed

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to the chorea stage of Huntington's chorea.

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This is not unlike a case you may have seen

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in other vignettes.

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But what is striking,

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along with the history which is necessary

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to make the diagnosis,

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is there's quite a bit of Sylvian atrophy.

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There is frontal atrophy.

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There's not much parietal atrophy yet.

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Look at the temporal horns.

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They are normal. They're basically pristine.

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There is no entorhinal cortex atrophy.

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There is no choroidal fissure widening.

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So, for someone to suggest an ALZ

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or Alzheimer's-like disorder would be imprudent.

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In addition,

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the patient has no vascular disease to speak of.

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So, you can't really come up with another good

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explanation for the patient's symptoms.

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And when you look at the caudate nuclei,

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they're pretty hard to dissect out

0:58

as separate structures.

0:59

Let's try it in the corona projection,

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even though it's just a standard T1.

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I mean,

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where is the gray matter signal of the caudate?

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Right there.

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It's very small.

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The frontal horns are bowing out laterally.

1:12

So when you have this combination of findings,

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paucity of anything else going on,

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atrophy that spares the mesial temporal region

1:20

and these puffy wide ventricles

1:22

in somebody with that history,

1:23

you almost have to make the diagnosis.

1:25

Now, this person had an additional weird history.

1:28

A relative, a cousin had neuroacanthocytosis,

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which is a chorea type illness associated with

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acanthocytes of the red cells, neuropathy,

1:39

myopathy, epilepsy, CPK elevation,

1:43

self-mutilation, and an eating disorder.

1:45

But this is another one of the choreiform

1:48

disorders that may be confused with

1:50

classic Huntington's disease.

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Now, in Huntington's disease,

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although we don't have it here,

1:55

you may see some abnormalities on SPECT.

1:58

You may see an elevated lactate level in the

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occipital lobes because the abnormality occurs

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as a toxicity in the mitochondria.

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So, it's no surprise that you might make lactate

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down low,

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low NAA in the basal ganglia.

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That's due to the cell loss.

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And NAA reflects cell neuron capacity or

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cell neuron density.

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The Creatine,

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the low basal ganglia creatine that you see with

2:25

this disorder correlates with the number of CAG repeats.

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So if the number of CAG repeats is 55,

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which is usually pretty bad,

2:33

then you're going to have a low creatine baseline

2:36

marker on SPECT imaging and PET in this region.

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And you may even see,

2:40

due to mitochondrial dysfunction and / or poisoning,

2:44

pyruvate in the cerebrospinal fluid at high field.