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I wanted to show another example of

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neuromyelitis optica spectrum disorder.

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This case is particularly good because it identifies

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on the sagittal FLAIR scan,

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a nice demonstration of the area postrema.

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So on this sagittal FLAIR scan,

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one sees abnormally high signal intensity along

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the posterior aspect of the medulla

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below the fourth ventricle.

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This is seen right here in this bright signal

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intensity area, which is the area postrema,

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which is characteristic of brainstem or

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involvement with neuromyelitis optica.

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Now, the back of the medulla has an area

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where it kind of bulges outward at the junction

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with the cervical spine.

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And this area is called the clava,

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which is intimately associated

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with the area postrema.

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You notice that the patient also has a few

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additional lesions within the pons.

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On the axial scan,

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we see lesions within the midbrain

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as well as the pons,

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as well as the area postrema,

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more on the right side than the left side.

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And then we start to get into the cervical spine disease,

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which I'll describe momentarily.

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These lesions do not show contrast enhancement.

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The patient had incidental post-traumatic injury

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to the occipital lobe.

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That would probably

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also affect the patient's visual acuity,

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but was unrelated to the demyelinating disorder.

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Let's look at the orbits.

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We have T1-weighted,

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T2-weighted scan with fat suppression

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and post-gadolinium enhanced scan.

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In looking at the orbits,

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we should probably make sure

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that there's no mass first.

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So, this patient shows no masses in the orbits.

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Patient does show evidence

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of a previous lamina papyracea fracture

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with herniation of fat through there.

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On the T2-weighted scan,

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we see small optic nerves,

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which are bright in signal intensity centrally.

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And as we get to the optic canal, bilaterally,

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we see bright signal intensity,

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left greater than right,

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but bilaterally within the optic nerves.

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On post-gadolinium enhanced scan,

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as we get to the optic canals,

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we see both of the optic nerves showing contrast enhancement.

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Let me magnify once again.

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Here you see the anterior clinoid process.

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And medial to the anterior clinoid process,

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is where the optic nerves go through the optic canals.

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In this situation,

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what we have is bilateral optic nerve

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contrast enhancement with gadolinium.

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As I scroll through them,

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you'll probably see it a little bit better.

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Here is the optic nerve through the optic canal.

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Again, anterior clinoid process,

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and then coming to the optic chiasm.

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Both of these optic nerves are showing contrast

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enhancement at the optic canal,

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as well as on the T2-weighted scan,

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very bright signal intensity going

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through the optic canal.

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So we have white matter lesions in the brain,

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in the area postrema, as well as in the brain stem.

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We have small optic nerves,

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suggesting that this is a multiphasic

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process with optic atrophy,

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but active demyelination as evidenced

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by the contrast-enhancing optic nerves

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at the optic canal, bilaterally.

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The next thing to look at would be the spine.

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And here you can see that this patient has

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longitudinally extensive white matter lesions

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in the cervical spine,

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as well as the thoracic spine.

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When we look at the thoracic

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spine on this STIR image,

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we are struck also by the decrease in

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the caliber of the spinal cord.

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We usually say that the spinal cord should

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subsume around 50% or more

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of the total spinal canal AP diameter.

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This is less than that.

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So, this patient has cord atrophy from multiple

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episodes of transverse myelitis.

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You can see cord expansion further superior.

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We would not expect this portion

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to show contrast enhancement,

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but the more active demyelinating portion could

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potentially show gadolinium enhancement.

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Let's see how well I did.

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So, here on our post-gad T1-weighted scan,

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in point of fact,

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we see no contrast enhancement

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within the spinal cord,

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and we can confirm that,

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on our axial scans,

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that there is nothing showing contrast enhancement.

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So nonetheless,

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this is probably two different age disease,

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the one with the cord atrophy being more chronic

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than the one which is showing some cord

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expansion, yet without contrast enhancement.

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The combination of longitudinally extensive

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transverse myelitis, optic neuritis,

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as well as the imaging findings in the brain

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at the area of postrema,

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suggest a diagnosis of

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neuromyelitis optica spectrum disorder,

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and it would be confirmed with serology

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for the aquaporin-4 antibodies.