0:00

This was a child who also presented with developmental

0:04

delay and the clinical history was with macrocephaly.

0:08

So in this instance,

0:10

we have a patient who has a white matter disease,

0:14

which, as you can see,

0:15

is bilateral and symmetrical on the

0:18

FLAIR and T2 weighted scanning.

0:21

And as opposed to the previous example of metachromatic

0:24

glucose dystrophy, we see that on this case,

0:27

the abnormality in the white matter goes

0:29

all the way out to the periphery.

0:31

By that I mean you see that there is high signal

0:35

intensity going to the subcortical white matter

0:38

of the frontal lobes.

0:41

And here on the T2 weighted scan,

0:43

we see it as well,

0:44

going all the way out to the cortex

0:50

with abnormal white matter disease.

0:53

This is a distinctly different pattern than what we

0:58

were seeing with metachromatic leukodystrophy.

1:01

This combination of macrocephaly with

1:04

a diffuse white matter disease,

1:06

which extends all the way out to the periphery

1:09

and involves the subcortical U fibers,

1:12

would be seen in patients with Alexander's disease

1:15

and Canavan's disease.

1:17

The next stop would be MR spectroscopy.

1:20

And what we would expect for MR spectroscopy,

1:23

in a patient with Canavan's disease,

1:26

is that huge spike in the NAA due to the deficiency

1:33

in the N-acetyl aspartoacylase enzyme.

1:37

So again, we would see the depression

1:44

of choline and creatine.

1:46

But what would be most marked would

1:48

be the elevation of the NAA peak

1:52

of

1:54

patients with Canavan's disease as

1:59

opposed to Alexander's disease.