0:01

So this patient is an 82-year-old female,

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who has a liver mass, and so I'm going

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to show you what that mass looks like.

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Uh, this was subsequently treated,

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and I'll show you what the

0:09

post-treatment scan looks like as well.

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Firstly, let's look at the pre-treatment scan.

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I'm going to show you the, uh,

0:14

post-contrast images, and we're going to

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focus on one of the liver lesions here.

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This is the T1-weighted,

0:21

fat-saturated, post-contrast sequence.

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This is the arterial phase, and I'm showing

0:26

you now the portal venous phase on this image.

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And we see a lesion.

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Right over here is in segment

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5, and it demonstrates non-RIM

0:37

arterial phase hyperenhancement.

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If we look at this lesion, it's more

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than, uh, 20 millimeters in size if we

0:45

were to measure it from here to here.

0:47

And in the portal venous

0:48

phase, this has washout.

0:51

This, in fact, also has a pseudocapsule that

0:54

surrounds this, and so you put it all together.

0:56

This is compatible with LI-RADS,

0:59

LI-RADS lesion, and in this particular patient,

1:03

had this one solitary lesion, relatively

1:06

small size, and so is deemed to be an

1:08

appropriate candidate for microwave

1:11

ablation therapy, which was performed

1:13

and a follow-up study was done after this.

1:17

So this is an image from the follow-up

1:18

study performed after ablation,

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if that, uh, LI-RADS 5 lesion in segment 5.

1:24

This particular sequence is a T1 FAT SAT,

1:28

pre-contrast image, and we can see quite

1:31

aa sizable cavity now, um, in segment 5.

1:35

And one of the reasons that when they do

1:37

these ablations, they not only ablate the

1:39

tumor, they ablate a margin around the tumor

1:42

as well, so the cavity ends up looking a

1:43

little bit bigger than the lesion itself.

1:46

Within this cavity there

1:47

is hyperintense ablation

1:49

T1 content.

1:50

That's not uncommon to see, particularly

1:53

when they do these percutaneous ablations.

1:56

This reflects hemorrhagic blood products.

1:59

This represents proteinaceous debris, alright?

2:03

But for practical purposes, when we see

2:05

this hyperintense T1 content on the

2:08

non-contrast image, we know that when we look

2:11

at the post-contrast images, we have to look

2:14

at the subtraction images to really see

2:17

if there is any true enhancement

2:18

underlying this high T1 signal.

2:21

And moving on to our post-contrast images,

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this is T1, Fatsat, post-contrast, arterial

2:27

phase, portal venous phase. Both of these

2:30

images are subtraction images, again,

2:34

to negate the appearance T1 content

2:37

that's expected after these ablations.

2:40

And we can see the ablation

2:41

cavity centered in segment 5.

2:45

And inside of it, this really looks avascular.

2:48

There's no internal

2:49

enhancement within this cavity.

2:51

Inside of it, it just remains

2:53

quite dark and black in appearance.

2:55

And around the periphery, you may argue there's

2:57

a little bit of very, very thin rim enhancement.

3:00

And that's okay.

3:01

We often see that degree of rim

3:03

enhancement following ablations.

3:05

The key thing, though, is to reevaluate that

3:08

small rim of enhancement on subsequent studies.

3:11

On any subsequent studies, it should

3:12

either look the same or get better.

3:15

Smaller in size, become less conspicuous.

3:17

It should never get thicker.

3:19

It should never become nodular

3:21

or get thicker like this.

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And once it starts to do that, you've got

3:24

to be worried about recurrent disease.

3:26

But in this instance, you don't see any of that.

3:28

And so this equates to successful

3:30

treatment of the thyroid's lesion.