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This is an MRI of the brain

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in a 15-year-old child who,

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when she was younger,

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had a cerebellar hemangioblastoma removed.

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There were no other lesions identified

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in her brain or spine, and there was no

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recurrence seen on surveillance imaging

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for a few years, and so all was well.

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She then presented with headaches, and

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an MRI showed this cystic appearing

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lesion with this enhancing component.

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Let's see on T2 weighted imaging.

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The cystic appearing part is very

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circumscribed, has central fluid contents

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that are hyperintense on T2 weighted imaging.

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The nodule does not demonstrate

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diffusion restriction; the central

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contents demonstrate facilitated

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diffusion, and that nodule is enhancing.

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So, for children and adolescents, a cerebellar

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lesion that is cystic with an enhancing

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nodule, it is very characteristic but it is not

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uniquely diagnostic of a pilocytic astrocytoma.

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In this patient, this is a hemangioblastoma.

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The differences are several

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fold in the clinical implication.

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First of all, in a pilocytic astrocytoma,

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the enhancing area enhances because of

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a leaky blood-brain barrier, but normal

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or even lower than normal blood flow.

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But because there's a leaky blood-brain

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barrier, the contrast accumulates in the

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interstitial space and actually accumulates

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more on progressive and delayed imaging.

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In a hemangioblastoma, this is

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related to arterial prominence.

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This is arterial enhancement; it

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enhances early, and just as importantly,

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is at surgery, it has the potential

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to bleed like an artery would bleed.

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So this patient who previously was thought

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to have a sporadic hemangioblastoma

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now has another hemangioblastoma,

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but that's not the only finding.

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There's another enhancing lesion in the

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contralateral cerebellar hemisphere,

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and if we go inferiorly, we see

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an enhancing lesion at the OBEX.

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While the OBEX lesion and the right

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cerebellar lesion appear solid, they also

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represent hemangioblastomas, just without

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the cystic component that occurs over time.

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The constellation of multiple

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hemangioblastomas is, in this case,

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diagnostic of von Hippel-Lindau syndrome.

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Von Hippel-Lindau syndrome has multiple

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hemangioblastomas that are typically

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either of the cerebellum or the spine.

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And one of the places where these

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hemangioblastomas often will occur is the OBEX.

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very much.

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which is important to look at because it's an

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area that can be missed on brain imaging, and

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it may be too high to look at on spine imaging.

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It also has the potential of resulting in

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a fourth ventricular outflow obstruction.

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Patients with Von Hippel-Lindau

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syndrome get other inherited tumors.

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One of the most common that

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people are aware of is renal cell

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carcinomas, which can be bilateral.

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It can be multicentric even in one kidney.

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So it's important when looking at

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spine imaging in a patient for Von

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Hippel-Lindau syndrome, when you're

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looking for spinal hemangioblastomas,

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to look as best you can at the kidneys.

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Similarly, when you're looking at abdominal

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imaging, to look for abdominal lesions of

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the nipple window to look at the spine.

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Now renal cell carcinoma is not the

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only abdominal and retroperitoneal

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tumor that they can have.

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They can feel chromocytomas.

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They can have pancreatic cysts.

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They can have pancreatic cell tumors.

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So these inherited tumor syndromes

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have a myriad of potential findings.

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Every single patient may have

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a different manifestation.

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No two patients will look exactly the same.

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So it's, well, it's important to be

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aware of what the characteristic, you

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know, lesions are and what, what a

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prototypical patient will look like.

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Look for all the possible findings.

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Now, there's another finding that is seen in

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the skull base in Von Hippel-Lindau syndrome.

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This patient does not have it.

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It's usually not seen until people

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are adults, but it is a papillary

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cyst adenoma at the endolymphatic sac.

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There's a variety of findings like that.

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They also can get.

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Retinal enhancing lesions that end up

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being equivalent to hemangioblastoma.

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Actually, Dr.

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Von Hippel of the Von Hippel-Lindau

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syndrome was an ophthalmologist.

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And prior to modern medical imaging,

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ophthalmologists were the only people who

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could non-invasively view the central nervous

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system through their fundoscopic exam.

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It's interesting that a lot of

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these neurocutaneous syndromes

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have eye manifestations, and some

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of which can be seen on imaging.

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So this patient has Multiple hemangioblastomas,

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and these are multicentric because each one is a

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separate entity that developed from a different

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mutation in the setting of a germline mutation.

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They're not metastatic lesions.

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They have multiple hemangioblastomas in

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the setting of Von Hippel-Lindau syndrome.

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And we can see their post-op day one imaging.

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You can see resection of this lesion

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here and resection of the OBEX lesion.

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And the Lesion over on the right cerebellar

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hemisphere surface was just going to be watched

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at this time, not because it was not felt to

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be important, but because it was not possible

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through a single approach to access both.

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So at this time, they did not go after

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this one, but they had a gross total

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resection of the left cerebellar lesion

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that was a cystic lesion with an enhancing

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neural nodule, and also the OBEX lesion.