0:00

Well,

0:00

we've just completed the

0:02

V of vitamin C and D.

0:04

That is the vascular lesions including

0:06

vascular malformations and vascular injury.

0:09

to the spinal cord from the standpoint

0:11

of spinal cord infarction.

0:13

So let's see where we could check off the V,

0:16

we could check off the infectious,

0:18

we can check off the trauma

0:19

we've dealt with.

0:20

We're now at the acquired

0:21

and metabolic disorder.

0:23

So the aim of vitamin C and D with regard to

0:26

the metabolic or acquired abnormalities

0:29

usually we're thinking about

0:31

deficiencies of vitamin.

0:33

Vitamin B twelve deficiency is known to

0:35

cause subacute combined degeneration leading

0:39

to loss of vibration and position sense due

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to its relative selective involvement of the

0:46

posterior columns of the spinal cord.

0:48

In addition to vitamin B twelve deficiency,

0:51

folate deficiency and copper deficiency can

0:55

also target the posterior columns

0:57

of the spinal cord. Nitrous

1:00

oxide toxicity is a rare cause of posterior

1:05

column injury to the spinal cord.

1:07

This is secondary to recreational

1:11

use of nitrous oxide.

1:14

Canisters in something we in college

1:17

used to refer to as whippets.

1:19

And this is effectively laughing gas,

1:22

which can, on an anesthetic basis,

1:25

or as I mentioned, in a recreational basis,

1:28

lead to injury to the posterior

1:30

columns of the white matter.

1:32

In addition to these metabolic

1:34

and acquired disorders,

1:36

selective involvement of the posterior

1:38

columns of the spinal cord may occur in

1:41

patients who have multiple sclerosis.

1:44

It may occur in tabes dorsalis,

1:47

which is spinal cord syphilis,

1:50

and it may rarely occur selectively in

1:54

vacuolar myopathy associated with AIDS.

1:59

Here we have

2:00

the classic appearance of a patient

2:02

who has subacute combined deficiency.

2:05

You note that there is signal

2:06

intensity loss,

2:08

brightness

2:10

in the posterior aspect of the spinal

2:12

cord on either side of the midline,

2:14

and usually this is fairly extensive over

2:17

multiple vertebral body levels.

2:20

This patient was a vegan and had the

2:23

B Twelve deficiency. On that basis,

2:26

normal B Twelve level greater than 250.

2:29

This patient had a level of 38.

2:31

The other situation where you may see this

2:33

in is in patients who have bariatric surgery

2:37

where they are not supplementing with B

2:40

twelve and they too may lead to a state

2:44

in which they get subacute

2:46

combined degeneration.

2:47

This may also be associated with pernicious

2:50

anemia and atrophic gastritis because with

2:53

atrophic gastritis they lose the ability

2:56

to absorb the B Twelve vitamin.