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This is an MRI of the brain

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in a twelve-year-old child

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with tuberous sclerosis complex.

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The FLAIR imaging shows multifocal areas of

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cortical dysplasia throughout both cerebral

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hemispheres, some of which are nearly confluent.

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Can be difficult to tell on some images where

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one area of dysplasia ends and

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what the next one begins.

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Can see this here on this coronal FLAIR image,

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can see multiple areas of signal abnormality.

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You can see the tapering for that typical

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focal cortical dysplasia,

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type two b morphology of the dysplasia.

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But as I said, in some places,

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they're relatively confluent,

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so it can be difficult to see any one individual

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lesion amongst each other.

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Within this patient,

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we see several areas of focally

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prominent perivascular spaces,

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or perivascular spaces within

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this area of dysplasia.

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And on post-contrast imaging,

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we can see that there are

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some subependymal nodules.

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Each of these subependymal nodules

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is something we look at.

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Then we look at susceptibility-weighted imaging

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to get an idea of whether or

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not they're calcified.

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You can see this area here has a

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little bit of calcification.

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This lesion is more calcified.

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That's the largest of them.

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So, I zoom in and I measure it.

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I'm getting about seven and a half millimeters

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by 6 mm, by approximately 8 mm.

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By size criteria,

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this doesn't meet the typical clinical imaging

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definition of a subependymal giant cell astrocytoma.

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over the course of several studies,

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this is a subependymal nodule that,

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based upon the susceptibility-weighted imaging,

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is predominantly calcified.

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Now, looking at some other sequences,

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this axial T2-weighted imaging,

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we could see an irregularity at the posterior

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aspect of the globe of the right eye.

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Now,

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this is close to the optic nerve head insertion,

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but just a little bit medial,

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or in the ophthalmologist terms,

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a little bit nasal, to the optic nerve head.

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So I do not think that this

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represents papilledema.

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This is not optic nerve head elevation.

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If we look on susceptibility-weighted imaging,

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we get a hint that there's a little bit of

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susceptibility hypointensity associated

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with this finding.

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And on post-contrast T1-weighted imaging,

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we're getting a little bit of a hint that

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there's some post-contrast enhancement.

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So while subtle imaging is not how you

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would formally make the diagnosis,

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but this looks like a lesion in the eye, which,

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in the setting of tuberous sclerosis complex,

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is likely an astrocytic hamartoma.

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An ophthalmologist through a dilated

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ophthalmoscope. Combination can confirm this.

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But these lesions especially when it's near the

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macula or possibly the optic nerve head,

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have the potential of being vision threatening,

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and they can watch them closely,

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and they might be amenable to therapy

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with mTOR inhibitors. MTOR,

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meaning mammalian target of

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rapamycin astrocytic hamartoma,

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are not a primary indication for mTOR

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inhibitors at the current time.

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But this is an example of, number one,

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why we should look at the entirety of the

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imaging sequences and all body parts within

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the images, if possible. Number two,

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being aware of the various manifestations

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of these diseases.

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Astrocytic hamartomas are a known association

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with tuberous sclerosis complex. And number three,

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it is why,

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in multidisciplinary tuberous sclerosis

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complex centers,

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they often have an ophthalmologist or a neuro

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ophthalmologist who works with them

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to follow these patients,

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because these images could go undiagnosed if not

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evaluated with dilated ophthalmoscopic examinations.

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So this patient has tuberous sclerosis complex

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with several subependymal nodules.

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Nothing that imaging-wise meets the criteria for

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subependymal giant cell astrocytoma and has what we

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think is an astrocytic hamartoma

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of the left eye.