0:02

Hello and welcome to Noon Conferences

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hosted by MRI Online. In response to

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the changes happening around the world

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right now in the shutting down of in-person

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events, we have decided to provide free daily

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Noon Conferences to all radiologists worldwide.

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Today we're joined by Dr. Kathryn McGillen.

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She is an assistant professor at

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Penn State Hershey Medical Center.

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She practices within the abdominal and

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thoracic sections with a focus on advanced

0:22

ultrasound techniques, including contrast

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enhanced ultrasound with a

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specialty in endometriosis imaging.

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A reminder that there will be time at the

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end of this hour for a Q and A session.

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Please use the Q and A feature to ask

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all your questions, and we'll get to

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as many as we can before our time is up.

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That being said, thank you so much

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for joining us today. Dr. McGillen,

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I will let you take it from here.

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Okay, thanks.

0:44

Uh, thanks to MRI Online for hosting this talk,

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and thanks to you all who are joining me, uh,

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for this introductory tour through contrast

0:50

ultrasound and some of its really cool indications.

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A small word of warning

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before we get started. There will be a few

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audience response cases peppered throughout this.

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Um, but I will let you know when they're coming,

1:01

and, um, I'm told you can move the box around if

1:03

it's blocking the image you're trying to look at.

1:06

So with that being said, let's get started.

1:10

Okay, so we're here to talk about microbubbles.

1:12

Um, this is my own little artist rendition, so it's,

1:15

you know, not the best, but I did what I could.

1:17

Um, but microbubbles in general, for contrast

1:19

ultrasound, they are smaller than a red blood cell,

1:21

which is important because they remain intravascular.

1:24

This is unlike CT or MRI contrast,

1:26

which diffuse out into the parenchyma.

1:28

These remain intravascular, and has a lot of the

1:30

cool stuff happens because of this factor.

1:34

So all of them have in common that they have a

1:35

lipid outer shell, which is echogenic on ultrasound.

1:38

So that's gonna be this part out here.

1:40

And then the central portion is contained usually of

1:42

a gas, in SonoVue or Lumason, as we call it in the US. Uh, its

1:46

made of sulfur hexafluoride, and definity, which

1:48

I spelled wrong, um, is composed of perfluorocarbon.

1:53

So these are a bit finicky, these microbubbles,

1:56

and they do burst with continuous ultrasound imaging.

1:59

So you have to be aware of what you're doing and

2:01

how long you're imaging in any particular plane.

2:04

What's cool about these is that there's no

2:05

renal-biliary excretion, since they do burst

2:08

either by the ultrasound itself or over

2:10

time, they, um, burst in the blood and then

2:14

they're exhaled—no renal-biliary excretion.

2:16

So we don't have to worry about those

2:17

factors. Because it is intravascular,

2:20

you can get multiple doses if

2:21

you burst all of the bubbles.

2:23

And it has a very safe risk and

2:25

allergy profile, which is great.

2:27

So, advantages for contrast ultrasound.

2:30

You get an image where you get the suppression

2:33

of the background tissue, which is essentially

2:34

a contrast-only image, which is really cool.

2:37

You get a true enhancement pattern of a lesion, unlike

2:40

a CT or MRI, where you're picking snapshots in time.

2:43

You can watch it for as long as you want to.

2:46

And then ultrasound in general is

2:48

high temporal and spatial resolution.

2:50

So you can see smaller septations and

2:51

nodules than you may be able to see on CT.

2:54

And again, it's intravascular.

2:56

So you can redose, unlike MRI or CT,

2:58

where contrast is in the parenchyma.

3:00

So you might have to wait, you know,

3:02

12–24 hours to redose somebody.

3:04

For patients, the advantage is that there's no

3:06

radiation, there's no renal excretion, so we're

3:08

not worried about their lab values beforehand

3:10

or after. A relatively safe allergy profile—

3:14

closer to MRI, much safer, fewer allergies

3:16

than people get with CT dye.

3:18

And then because it is ultrasound, there

3:20

is a cost savings compared to CT or MRI.

3:23

So disadvantages: if you do find

3:25

a tumor, you can't stage it.

3:26

This is ultrasound.

3:27

You're limited to what you can see.

3:29

It has the same depth and habitus issues

3:31

that ultrasound in general can have.

3:34

Um, with these you take a lot of cine clips, so

3:36

there can be, um, PACS and archiving issues.

3:38

At some places they create really large

3:40

files, and while you can look at multiple

3:42

lesions, 'cause you can dose multiple times,

3:44

you know, if you say had 10 lesions, that's

3:46

gonna be a limitation of contrast ultrasound.

3:49

So in general, it's a problem-solving tool.

3:52

If you have a very specific question,

3:53

it's really good for answering that.

3:56

So to go over how the imaging's done, it is done

3:59

in a low B-mode, and that's to avoid bursting

4:01

those bubbles. If you use the regular ultrasound,

4:03

you will burst them very, very quickly.

4:05

It does use harmonics, which is near-field imaging.

4:08

And unlike regular ultrasound, your focal

4:10

zone is going to be beyond the lesion itself.

4:13

And that's because you need the ultrasound beam to

4:15

penetrate the lesion completely before it diverges.

4:20

You don't want the lesion too close to the

4:21

transducer, 'cause you can get some artifacts,

4:23

but too far, it's a little Goldilocks here.

4:26

Um, less than 10 centimeters is generally optimal.

4:28

There are some systems out there that are

4:30

allowing better depth, up to 20 centimeters

4:32

or so, but most systems out there right

4:34

now, less than 10 centimeters is optimal.

4:37

And then after that, you wanna avoid

4:38

attenuating structures if you can.

4:40

So for example, you don't wanna image through

4:41

the spleen as a window to get to the kidney.

4:44

Sometimes you have to, though.

4:46

So what to do?

4:47

Here's an example of a Lumason.

4:48

Before it's used, it looks like a

4:49

little white powder at the bottom.

4:51

Uh, patients will need an IV,

4:53

generally 20 gauge or larger.

4:54

Again, because the bubbles are finicky.

4:56

If you have a smaller IV, you could burst them.

4:59

In our institution, the sonographer

5:01

does the pre-scanning with gray scale.

5:02

Before they show the

5:03

radiologist, they mix the contrast.

5:06

In general, these bottles or these vials come with a

5:08

total of five milliliters once you

5:10

reconstitute it, equivalent of about two liver doses.

5:15

The radiologist in our institution injects

5:17

the contrast and directs the imaging

5:19

of how long we wanna image at any time.

5:21

How long do we image overall? Up to five minutes or so.

5:24

At what points do you wanna image?

5:26

We would direct that.

5:27

And then you remember, just like ultrasound,

5:29

you can image in any plane. Patient can

5:31

be in any position, so they can be sitting

5:33

upright if that helps them to breathe better.

5:35

And if you can get a lesion within the right

5:38

plane, you can even image while the patient breathes.

5:40

Um, by keeping it in-plane, which

5:42

you can't really do with CT or MRI.

5:45

So here's the setup.

5:46

This is a reconstituted vial, Lumason.

5:48

It comes with a sterile saline syringe in the packet.

5:51

Looks like a sort of cloudy, white, milky material.

5:54

Once it's reconstituted, you gotta shake

5:56

it because it comes out very easily.

5:58

You have a three-way stopcock.

5:59

And what's important when you put this together

6:00

is that the contrast has to be at 180 degrees.

6:04

If you put it at the 90 degrees,

6:05

it doesn't like this sharp turn.

6:07

The bubbles are finicky, they break, and

6:08

then you get less contrast going into—

6:10

you get your image to be suboptimal.

6:12

So remember to always place it that way, 180 degrees.

6:15

So let's look at some pictures.

6:17

Let's start with the liver.

6:18

This is a busy slide.

6:19

This is from Burrows and Radiographics,

6:21

but it's a great slide, and if you

6:23

just concentrate at the top part.

6:25

This is really where your, your, your tree is.

6:27

Is there portal venous or late phase washout?

6:29

Yes.

6:30

Malignant. No, benign.

6:31

That's pretty much it.

6:33

It does get a little bit more complicated, of course,

6:35

'cause there's different patterns of enhancement,

6:37

of benign things, and there's different patterns of

6:39

enhancement of malignant, which we'll get to in a bit.

6:41

But this is really your tree right here.

6:43

Portal venous.

6:44

Does it wash out or not?

6:46

So here's, uh, to start with benign.

6:49

This is the cyst.

6:50

There's no enhancement.

6:51

You can see here, this is our low B-mode right here.

6:54

This is our subtraction, um, contrast image.

6:57

And you can see it's not pretty.

6:58

They don't look like cysts.

6:59

They're kind of hypoechoic on low B-mode.

7:01

The MI is 0.04, so it's low. It's not pretty, but you

7:06

can see the increased through-transmission behind it.

7:08

And here we are about 26 seconds after injection.

7:11

You can see there's absolutely no enhancement.

7:13

We still get the same artifact of

7:15

increased through-transmission.

7:16

On the contrast part of it here, um, you couldn't

7:19

make a diagnosis of a cyst off of just one image.

7:22

You need to prove that this didn't arterial enhance.

7:24

But this is the representative image.

7:26

Black hole, no enhancement.

7:27

This is a benign cyst.

7:30

So this is case one.

7:31

I'll have you pay attention to this.

7:32

On the next slide you'll get your

7:33

first question, the audience response.

7:36

So this is a patient who had an MRI.

7:38

This is the lesion in question, just

7:40

so you know what we're looking at.

7:42

So this is our T2-weighted image.

7:44

This was an outside MRI, so I don't know

7:46

what the read was, but they came to contrast

7:47

ultrasound, so I assume it was an indeterminate.

7:50

So a pre-contrast T1.

7:52

I have a couple post-contrasts here.

7:54

I have no subtraction images.

7:55

So with that in your mind, my best guess

7:57

is that they were concerned whether this

7:59

was true rim peripheral enhancement in the

8:03

lesion, or whether this was just artifactual.

8:05

So it came in contrast ultrasound.

8:08

Here's our gray scale, and here's

8:10

a clip of our post-contrast.

8:11

So if we can bring up that first question, the

8:14

question's going to be, and you can move this, is

8:17

it benign or malignant based off of the pattern?

8:22

And I will, as you're thinking about it, I

8:24

will point out that this lesion was right at 10

8:26

centimeters, so you don't see the back portion of it.

8:30

So if you were doing this in real life, you'd probably

8:32

reposition the patient for a second dose to get all

8:35

of that lesion within 10 centimeters of the probe.

8:39

Okay, great.

8:40

Great job.

8:40

So 87% said benign, and that's what this was.

8:43

There's no enhancement.

8:44

So we have very early, six seconds

8:46

after the contrast arrived.

8:48

Another one at 30 seconds, about a

8:50

minute, and then a minute and a half.

8:51

At this point, it's a black punched-out hole.

8:54

We don't see any definitive enhancement.

8:55

This is a cyst, even though it looks

8:57

kind of ugly here on the ultrasound.

8:59

Wasn't clear on the MRI.

9:01

We proved this was a cyst.

9:02

There's no peripheral enhancement.

9:03

This is isoechoic around this guy the entire time.

9:06

Stayed this way on

9:07

more delayed imaging.

9:08

This is a cyst.

9:09

End of story.

9:10

Don't need to do any further follow-up or workup.

9:13

Okay, so talking about more

9:15

benign lesions, go to hemangioma.

9:18

So these act very much like they do on CT or MRI.

9:21

So they can flash fill, or they

9:23

can fill in over several minutes.

9:25

And because they are slow flow, you wanna image

9:28

sparingly, or you can consider doing a second dose.

9:30

With the second dose,

9:31

you don't even image in the arterial

9:32

phase; you just wait till you have three,

9:34

four minutes out to see what happens.

9:36

And that is because if you image a hemangioma

9:39

the entire time, you just sit that probe

9:41

right on it, you're gonna cause late washout.

9:44

And that's because hemangiomas

9:45

are generally slow flow.

9:47

Vascular malformations.

9:48

So if you sit that ultrasound on it, you're

9:50

gonna burst the bubbles within the hemangioma

9:52

faster than those in the circulation,

9:54

and you cause a late washout artifact.

9:56

So that's something to be very aware of.

9:58

And that may be, if you're doing that, the

9:59

second dose may then help because you can

10:01

just wait and see if there's washout.

10:03

So here's an example.

10:04

This is a patient who had a history of trauma.

10:07

So she had some scarring over her liver and

10:09

had this big echogenic lesion right here.

10:12

She did not want an MRI because she'd

10:13

read about, um, gadolinium deposition

10:16

in the brain and just didn't wanna—

10:18

didn't wanna deal with it.

10:19

So she came in contrast ultrasound.

10:21

So here's the first image.

10:22

Again, I cut these a little bit,

10:23

but this is your gray scale.

10:24

And again, you can see not a pretty image, right?

10:27

But we knew we were on the lesion,

10:29

and that's what this really is for.

10:30

It's to help you know where you are.

10:32

So at this point, very early on, you

10:33

can see some peripheral enhancement.

10:35

And at this point, I don't know if this

10:36

is gonna be a malignant peripheral pattern

10:38

or if this is going to be something else.

10:40

So we watched, and now you start to see

10:42

maybe 30 seconds or so later, we now

10:44

have these kind of puddling of contrast.

10:46

This peripheral, this nodular,

10:48

discontinuous enhancement.

10:50

You know, waited another minute, took another

10:52

snapshot, and starting to fill in, right?

10:54

There's less centrally here, starting to fill.

10:56

In super delayed imaging, completely filled in.

10:59

And what's cool about this too is

11:00

you can see background liver contrast

11:02

is already starting to go away.

11:03

There's not a lot of contrast left in the

11:05

liver, but this is still holding onto it.

11:07

This is like a persistent enhancement pattern.

11:09

So this is a benign hemangioma.

11:11

She doesn't need an MRI, she doesn't need follow-up.

11:13

That's what this is.

11:15

Just to talk very quickly about regenerative

11:17

nodules. In my practice we do a lot of, uh,

11:20

cirrhosis patients, a lot of imaging of that.

11:22

So this comes up a lot.

11:23

These little tiny hypoechoic nodules in a

11:25

background of an echogenic liver that's cirrhotic.

11:28

It's a little bit of kidney right here, a little

11:29

bit gallbladder to let you know, regenerative

11:31

nodules can either isoenhance to background liver.

11:34

Again, my little drawing, not the best, but

11:36

did what I could. Or they can arterial enhance.

11:38

But what's important in how you differentiate these

11:41

is they are all isoenhancing on the delayed phase.

11:44

So here's a little nodule. Here we are on

11:46

arterial phase, and I put a little arrow here.

11:47

This was it right here.

11:48

And it's pretty much isoenhancing to liver around.

11:51

It looks pretty similar.

11:52

Here's the kidney enhancing on the delayed phase.

11:55

Again, here it is right around here,

11:57

and it's not really washing out.

11:59

You know, at first glance I was like, oh,

12:00

is this washed out or is it right up here?

12:02

Either way though, this is similar to

12:03

this, similar to this, similar to this.

12:04

It's not below background.

12:06

This is not washing out.

12:07

It's iso.

12:07

This is the regenerative nodule.

12:09

Just keep a close eye on it.

12:11

And then there are the category of challenging but

12:14

benign lesions, and that is your FNH and your adenoma.

12:17

If you're starting out in a practice with

12:19

this, I would not start with these cases.

12:20

I would not start with, you know,

12:22

the 20, 30-year-old females.

12:23

We're trying to differentiate these. These are

12:25

difficult, just like they can be in CT and MRI. But the

12:30

differentiating factor is this early arterial phase.

12:33

They're both gonna arterially enhance

12:34

early, just like they do on CT and MRI.

12:36

Difference is adenomas have this centripetal

12:39

type pattern of filling, whereas the FNH has a

12:42

centrifugal start centrally and kind of branches out.

12:45

So this early phase imaging, you

12:48

need to be watching very closely.

12:49

This happens so rapidly.

12:52

Other things that can differentiate: they

12:54

can both have this sustained enhancement,

12:55

but adenomas can have a weak washout.

12:58

So not super punched-out dark hole, but

13:01

just a mild washout. They can have that.

13:03

So let's show you some examples.

13:05

This was actually a male patient who had

13:07

a fatty liver, not cirrhotic, um, who

13:10

had an indeterminate lesion on CT/MRI.

13:12

It just wasn't clear what it was.

13:13

So it came to contrast ultrasound.

13:15

You can see it right here, kind of ill-defined,

13:16

hypoechoic in the background fatty liver.

13:20

And here it is super early on this kind of

13:23

centripetal type pattern where it fills in right here.

13:26

So we thought this is gonna be an adenoma.

13:28

And you can see this one's at 16 seconds.

13:31

You know, 15 seconds or so later, the

13:33

whole thing was just diffusely arterially

13:35

enhancing above background liver behind it.

13:38

Right?

13:38

So now we have an arterial enhancing lesion.

13:40

Thought it was probably centripetal.

13:42

So we go to delayed, and at three

13:43

minutes, there it is again.

13:45

You can see it has a mild washout.

13:47

We've got these little speckles still in

13:48

it, but it's definitely below background.

13:51

So if this was a cirrhotic patient, I would be worried

13:53

about an HCC, but I was assured he was not cirrhotic.

13:56

He was just a fatty liver at this point.

13:58

So I said, this is probably an adenoma.

14:00

We did not end up biopsying it, but we did have, um—

14:03

three months of stability, and

14:05

it's exactly the same size.

14:06

That's probably what this is.

14:08

Even though it was a male patient,

14:09

it's probably 'cause of background

14:10

fatty liver.

14:12

Here's another case, um, just to show you,

14:14

'cause we don't see a lot of these adenomas.

14:16

I'm gonna show a couple examples.

14:17

This was a 24-year-old female who had this

14:19

incidental large right lobe liver lesion.

14:23

So in arterial, um, time.

14:25

This a little bit quickly, at

14:26

five seconds, centripetal filling.

14:28

Not an easy one to figure out what this was.

14:30

This is one of our earliest cases,

14:31

and I'll admit we flubbed it.

14:33

Um, but centripetal filling, it's

14:34

definitely arterial enhancing very early on.

14:37

And then by five minutes, we

14:38

followed this out a long time.

14:39

You can see in the liver over here, liver right here.

14:42

We've lost almost all the contrast,

14:44

but the lesion is still enhancing.

14:47

So that is not a malignant pattern.

14:48

This is a benign pattern.

14:52

And so in retrospect, this is centripetal filling,

14:54

but because we weren't sure—this was one of our first

14:56

cases—she did get an MRI, and here you can see in

14:59

her T2, it's heterogeneously mildly T2 bright.

15:03

Sort of iso, but heterogeneous on your pre-

15:05

contrast, very bright on your arterial phase.

15:08

Imaging then becomes a little bit more

15:11

iso, but never completely enhances.

15:13

Still iso and delayed on our 20-minute VIBE phase.

15:16

It is not brighter than background, so it does

15:18

not, would not fit with an FNH classically.

15:21

And this was the money right here.

15:23

This was our in and out-of-phases.

15:24

And you can see there is drop-out of

15:25

signal in this lesion on the out-of-phase.

15:27

So it does contain fat.

15:29

And this was, um, eventually

15:30

biopsied, um, surgically removed.

15:32

And this was an adenoma, given its large

15:34

size, capsular position, risk of rupture.

15:38

So tough case.

15:39

So let's move on to the malignant cases.

15:40

So again, going back to the

15:41

Burroughs Radiographics article.

15:44

Malignant lesions—what they do is

15:45

arterially enhance, and they wash out easy.

15:47

That's it.

15:48

It is, of course, a little bit more complicated

15:51

than that if you're looking for an HCC.

15:53

And again, generally you're gonna have a

15:54

specific population where you're looking at this.

15:57

They're going to arterially enhance—either

15:58

dysmorphic, looks like an adenoma a little bit, right?

16:01

Or hyperenhancement early arterial,

16:05

late phase, which is what we normally

16:06

time the CT and MRI for—still enhancing.

16:08

And then you get this late mild washout.

16:11

So it is below background, but it's got

16:13

this kind of speckle of enhancement,

16:14

sort of a hypoenhancement pattern.

16:18

Other malignant lesions.

16:19

Metastases. They arterial enhance, but they

16:22

may peripherally arterially enhance, but

16:25

they have rapid and pronounced washout.

16:27

So by the late arterial phase, unlike an

16:29

HCC, they're already starting to wash out.

16:31

And when you get to the late phase, it's like a

16:33

punched-out black hole—almost looks like a cyst.

16:35

So this is the differentiation right here.

16:38

So with that in mind, the question is: how long

16:40

do I scan when I'm looking at a liver lesion?

16:42

So you do need to do intermittent, 'cause you—if

16:45

you wanna image out to four or five minutes, you're

16:46

gonna burst bubbles if you watch the whole time.

16:48

And you have to look through all of those images too.

16:50

And if they're not helping, I don't

16:52

like to take them, so clearly you have to

16:54

image through the entire arterial phase.

16:56

That's how we differentiate so many of these lesions.

16:59

I like to go entirely through one minute,

17:01

because that's when that rapid washout

17:02

is going to occur—within that one minute.

17:04

So that's gonna differentiate when I'm

17:06

worried about HCC versus other malignancy.

17:09

That one minute is crucial.

17:12

From there, I use intermittent delayed imaging.

17:14

Usually I start up again around three minutes,

17:15

to match our CT protocols and MRI protocols,

17:18

usually up to five minutes, but you can

17:20

go a little bit longer if you need to.

17:23

And because this is the longest phase, I

17:25

tend to scan through the rest of that liver,

17:27

liver lobe, whichever lobe I'm in, because

17:30

it's a long phase, uh, washout phase.

17:32

So you can look for any other additional lesions that

17:34

you may have missed on the arterial or the gray scale.

17:38

So ACR has a LI-RADS for specifically contrast-enhanced

17:42

ultrasound. It is not the same as the ultrasound LI-RADS.

17:45

Um, and it uses your L3, L4, and 5s,

17:47

and pretty much the same up here, right?

17:49

Typical phase enhancement.

17:50

Does it have washout—late and mild, yes or no?

17:53

But what's important here, and I

17:55

found here, is the LI-RADS M category.

17:57

We don't tend to use this a whole lot in CT/MRI.

18:00

I've used it more in contrast

18:02

ultrasound than I ever have in

18:03

CT/MRI. So I'm gonna focus on this for a second.

18:06

So LI-RADS M—meet any of the three criteria:

18:09

rim arterial phase enhancement, or early—

18:13

meaning less than 60 seconds—washout.

18:14

And again, that's why I image through 60 seconds.

18:17

Or marked washout, and that's the delayed,

18:19

when it looks like a punched-out lesion.

18:21

So the next question is, what does LI-RADS M mean?

18:23

That's what your hepatologist will wanna

18:25

know if you start saying this category.

18:27

So this is from VanderPol, 2019.

18:29

This was from CT and MRI, not from contrast-enhanced

18:33

ultrasound, but they did look at the LI-RADS M category.

18:36

They were almost all malignant—93%,

18:39

which is somewhere between LI-RADS 4

18:41

and 5 categories for malignancy.

18:43

And a little bit more than a third of them were HCCs.

18:46

So in general, if you call LI-RADS M, a third

18:49

of a chance it's gonna be an HCC, and then

18:51

somewhere around a third of a chance

18:52

it could be a mixed HCC–intrahepatic cholangiocarcinoma,

18:56

or it could be a cholangiocarcinoma. Less likely some

18:58

other malignancy, but certainly possible.

19:00

So that's what a LI-RADS M means.

19:01

A lot of times these need to

19:02

go to biopsy or further workup.

19:05

So let's see some more cases.

19:06

This was a 63-year-old male who had

19:09

hepatic fibrosis and came in for screening.

19:11

So we noticed he had a pretty heterogeneous

19:13

echogenic liver up here, and almost like this

19:15

geographic, like less echogenic liver back here.

19:18

And we're like, is this, is this a nodule right

19:20

here, or is this just part of, like, the whole

19:22

geographic, you know, change in this liver?

19:26

So we enhanced him.

19:28

And so you can already see the bubble

19:29

starting to flow in right here.

19:32

And we're having him just quietly breathing right now.

19:34

Now he takes a deep breath, we can see the hepatic

19:37

artery and the portal veins start to fill in there.

19:39

Portal vein's gonna come in in just a moment.

19:41

Here goes kidney,

19:44

breathing.

19:45

And now we're starting to see a lot of vessels here.

19:46

Right there is your portal vein,

19:48

and there's the lesion right there.

19:49

Arterial enhance—this guy

19:50

right here, arterial enhancing.

19:52

So by 30 seconds, this was already arterially enhancing.

19:55

He's gonna take another breath here.

19:56

Gets a beautiful vasculature in his liver.

19:58

Big breath there.

20:00

We come back through the liver.

20:04

Right here.

20:05

You can already see centrally.

20:06

This is starting to wash out by 46 seconds.

20:09

This was already starting to wash out, so

20:10

I'm already concerned seeing this, that this

20:13

is a LI-RADS M. Despite that he has cirrhosis,

20:15

fibrosis again.

20:16

Here it is right here, starting to wash

20:18

out, no longer that big arterial lesion.

20:21

So moving on to three minutes.

20:23

We'll see what happens.

20:24

This is gallbladder right here.

20:31

And there you go.

20:32

So this is sort of a punched-out lesion, little bits

20:34

of enhancement in it, but this is the marked washout.

20:38

And we'll swing back through in just a moment here.

20:42

And this is us scanning too, looking

20:43

for any other lesions. Punched-out lesion

20:45

right there that's pretty washed out.

20:47

So we call this a LI-RADS M, and because

20:50

the hepatologist is like, "You guys don't

20:51

say LI-RADS M very much from CT and MRI.

20:54

What does that mean?

20:55

Let's get a CT."

20:56

So they did, and this, I would argue, is a very

20:59

well-timed arterial phase, late arterial phase CT.

21:03

And I would challenge you to find a lesion

21:04

on this, and I will tell you it is on this

21:06

particular image. It was a right lobe lesion.

21:09

This was the delayed phase, and I

21:10

have it windowed fairly harshly.

21:12

This was three minutes.

21:13

And I'll tell you that our attending was

21:14

reading this, called me and said, "You know what?

21:16

I know what you saw on the contrast ultrasound.

21:18

It looks really convincing, but I don't see

21:19

anything on the CT that I can definitively call."

21:23

And so, because I'm obsessed with this,

21:24

I actually looked at the non-contrast,

21:27

which doesn't usually help a whole lot.

21:29

And here it is.

21:30

Now you can see this, and it looks just like

21:33

the arterial enhancement of the contrast.

21:35

If you go back.

21:36

And you squint.

21:37

This is a little, little bit

21:39

of enhancement right here.

21:40

Little bit of washout right there.

21:42

Super hard to see on a CT.

21:43

I think if this person had gone to a four-phase CT,

21:45

this probably would've been called negative or maybe

21:48

LI-RADS 3, or I don't think they would've come

21:51

down on tumor on this based off of the CT scan.

21:54

But super obvious on contrast

21:55

ultrasound. He ended up going to TACE.

21:58

So this is another patient, different example.

22:00

This was a 59-year-old cirrhotic.

22:02

He had a normal four-phase CT three months

22:05

before, but he came into the hospital in acute

22:07

decompensating liver failure and renal failure,

22:10

was about to get a transplant, and they just wanted

22:11

to make sure that there was nothing huge going on

22:14

that would take him out of transplant criteria.

22:16

So he has ultrasound. You can see he has cirrhosis,

22:19

and we found the liver lesion up near the dome.

22:22

You can see we are below our

22:23

10-centimeter mark right here.

22:25

The ascites again, because ultrasound

22:27

travels quicker through fluid, helps a little,

22:29

bit so we could get a little bit deeper,

22:31

so we couldn't get that lesion any closer.

22:34

So here we are in the arterial phase.

22:35

So we're at 41 seconds, approximately.

22:37

Here's your lesion right here.

22:40

And we struggle.

22:40

We're like, well, that looks like it's enhancing,

22:42

but it's not enhancing to liver above it,

22:44

but it's enhancing to liver next to it.

22:46

And that's what's important.

22:47

Is it enhancing compared to

22:48

background at the same level?

22:51

One caveat with this is you have to make sure

22:52

you're not imaging between ribs, and this

22:54

is just rib shadow, but you go to your gray

22:56

scale and you can see I have liver over here.

22:58

I have liver over here.

22:59

This is just contrast not picking up.

23:01

This is an enhancing lesion.

23:03

So if you weren't sure, you still go

23:05

to your delayed phase at three minutes.

23:06

Here's your lesion again.

23:07

And here we have washout.

23:09

We have speckles on there.

23:10

It's hypoenhancing, but it

23:11

is much less than background.

23:13

So we called this a LI-RADS 5.

23:16

He ended up going to liver transplant shortly after.

23:19

And this was proven on explant to be an HCC.

23:25

This is a look at his CT, his four-

23:27

phase CT from three months earlier.

23:28

Because whenever I find these, you

23:29

always look back just to see if you can

23:31

learn from it, if you can see something.

23:32

And I would argue if you, um, window it

23:35

pretty harshly and squint your eyes,

23:37

there's the lesion right there.

23:38

I think you can see the washout a little bit better.

23:40

This was a vessel washout right there.

23:42

There's the enhancement.

23:43

So again, I think contrast ultrasound is still not

23:46

the easiest case, but you could see it much more

23:48

definitively than the CT where it was not seen.

23:52

Okay, this is case two.

23:53

This is gonna be the next audience

23:54

response in just a moment.

23:56

This was a 74-year-old female.

23:58

She had cirrhosis.

23:59

She had an indeterminate dome lesion, which

24:01

we measured here, but the outside imaging

24:03

was not available for direct comparison.

24:06

So she had some renal failure, so they

24:07

didn't wanna give her a CT or an MRI.

24:10

There's your Doppler.

24:12

And so here comes question two.

24:14

So here's your arterial phase.

24:16

Lesion, I'll tell you is right here.

24:18

We did image between ribs.

24:19

In this case, that's a rib shadow,

24:22

and here's your delayed phase.

24:23

If we can bring up question two, how

24:25

would you LI-RADS category, this lesion?

24:27

She is a cirrhotic.

24:33

Oh, and I have a little box.

24:34

So there we go.

24:36

Here's your little reminder of the categories.

24:38

I don't expect you to memorize that.

24:42

Okay.

24:43

So tricky one, right?

24:44

This is a hard one.

24:45

This was actually the first case we ever did.

24:47

So I was like, we have to be right.

24:48

We have to be right on this one because I wanted

24:50

to grow this business and prove that it worked.

24:52

So this ended up being, if you

24:54

look here, so there's our lesion.

24:56

This is our arterial phase enhancement.

24:59

So this is enhancing, and it's diffusely enhancing.

25:01

And then here at five minutes, lesion's right here.

25:04

And it's not really that punched

25:05

out look, it doesn't look cyst-like.

25:07

It's just kind of vaguely hypo

25:09

enhancing compared to background.

25:10

There's a little bit less enhancement in

25:13

here than there is the background around.

25:15

So we called this a RAD because it was greater

25:17

than 10 millimeters, and because this was our first

25:21

case, her renal function improved a little bit.

25:22

We called this malignant.

25:23

They wanted to get a CT.

25:25

And so here you go.

25:26

Here's your arterial phase.

25:27

Very subtle dome lesion, but it looks

25:29

pretty much the same size as what we saw.

25:31

Very clear.

25:32

Washout.

25:33

So this was called LI-RADS 5.

25:34

She went to TACE, there's your lesion right there.

25:37

So one year later she came back for follow-up.

25:39

She came, she did CTs in between,

25:41

but her renal function went down.

25:42

So she came back for contrast ultrasound, and

25:44

now we found a sort of bilobe appearance.

25:46

Looked a little bit different than it

25:48

did that first time around, and weird,

25:50

you know, color Doppler in that area.

25:52

So we enhanced her again.

25:54

And gray scale's not pretty, right? But you can see

25:57

there is a bilobe enhancing lesion right here.

26:00

That's early. Go to delayed around three minutes.

26:03

Here's your lesion here, and this is super subtle,

26:05

but you can see here, I think the arrows help

26:07

point it out.

26:07

This is vaguely hypoenhancing

26:09

compared to the rest of the liver.

26:11

This part of the lesion up.

26:12

Here was iso liver, but this part was less.

26:15

So we said, you know what?

26:16

I think this is treated. She's been TACE. I think

26:18

the upper part was TACE and treated appropriately.

26:21

I think this is residual tumor down here.

26:23

'Cause we have enhancement and we have washout.

26:26

And again, because this was early on, um, she did

26:29

end up getting a, I think they just followed her.

26:30

They got a CT in three months.

26:31

And so this shows you, here is the, the higher

26:34

lesion, which is completely TACE, right?

26:36

Completely treated, at least on this image.

26:38

And here's the second bilobe lesion, which already

26:39

looks like it's incompletely treated, right?

26:42

We don't have a circular TACE there.

26:43

We just have a little bit of rim there.

26:45

So you look at the arterial and washout

26:47

of the inferior lesion, and there's some

26:50

subtle enhancement, subtle washout.

26:51

So this matched what our contrast

26:53

enhanced ultrasound said.

26:54

She went back for a second TACE for,

26:56

uh, this incompletely treated lesion.

27:00

Okay, so we talked a lot about, um, cirrhotic.

27:03

So how about what does a metastatic lesion look like?

27:05

So this was a 56-year-old male

27:07

with melanoma on treatment.

27:08

He had this isolated liver lesion.

27:10

A little bit of central, probably necrosis, right?

27:13

Not a lot of color Doppler flow to it.

27:16

And here's our contrast imaging.

27:19

So our lesion is right here.

27:21

So keep an eye on this space.

27:22

See the, the bubbles start to flow in.

27:24

And this happens very rapidly.

27:26

We have rim enhancement right here.

27:28

We have rim enhancement, and now

27:30

it's already starting to wash out.

27:33

So I'm gonna play that again because there

27:35

is a perfusion artifact that occurs up here.

27:37

I'll show you it on the CTs.

27:39

So try not to watch that.

27:40

It's very easy to get distracted by it.

27:43

So there, right around here we have rim enhancement.

27:48

And then you get just to here and

27:49

it's already starting to wash out.

27:51

You get this hypoechoic portion.

27:52

So this is washing out within 30 seconds.

27:55

So this is a malignant pattern.

27:58

So here I, I annotated all these, especially

28:00

in the beginning when we were starting these.

28:02

Here's your enhancing rim.

28:03

I would argue this rim was much smaller than what

28:05

I thought it would be based off of the ultrasounds.

28:07

If I was biopsying this, I may have gone a little

28:10

bit too centrally and missed the viable tissue.

28:13

Here we are at just under one minute, and you can

28:15

see the whole thing is almost already washing out.

28:18

Less than a minute, delayed.

28:20

Phase at

28:20

three minutes, punched out.

28:21

Looks almost like that cyst that I showed you early on.

28:24

This is marked washout on the delayed phase.

28:26

So this is consistent with a

28:28

malignant pattern of washout.

28:31

And again, because this was early on when

28:33

we were doing this, he, uh, or he happened

28:35

to have a CT I think a few months earlier.

28:37

Which showed, there's your perfusion change right

28:39

there, which we had right here, the same match.

28:41

And again, we, we imaged, you

28:43

know, from below aiming up.

28:44

So that's why this was closer to the probe.

28:46

But the lesion looked the same, right?

28:48

Central necrosis, we're getting the same information,

28:50

maybe a little bit more 'cause you know which

28:52

tissue is viable if you're gonna biopsy.

28:53

It also had a PET shortly after the contrast

28:56

ultrasound, which shows the same thing.

28:58

This rim of tissue that is

29:00

viable, the central part is not.

29:02

So again, this can help you with a biopsy if you have

29:04

this patient on the table right then and right there.

29:07

Okay, so this is case three.

29:08

So this is our next audience

29:09

response right after this one.

29:11

So this patient had multiple hemangiomas in their

29:14

liver, but they also had a concerning lung lesion.

29:17

And they asked, um, for biopsy.

29:18

And I was on biopsy that day and I said,

29:20

you know, most of these I think are

29:22

hemangiomas, but I'm not sure what this

29:24

one is and I'm not sure what this one is.

29:26

So we got the MRI and you see,

29:28

you know, mildly T2 bright, right?

29:29

Looks like this.

29:29

Hemangioma back here though.

29:30

I'm not impressed.

29:31

Pre contrast.

29:33

Early phase, this guy enhances. This one,

29:36

maybe.

29:36

Maybe something's happening in

29:37

there a little bit more delayed.

29:40

Hard to say for sure.

29:41

Hard to say for sure what's going on out there.

29:44

And then here it is on a

29:45

little bit more delayed phase.

29:46

So I personally felt that this was not conclusive.

29:49

This could still be a real slow flow hemangioma,

29:51

given the T2 signal.

29:53

Um, it did not restrict diffusion.

29:55

I wasn't convinced. I didn't really wanna

29:56

biopsy this if this was a hemangioma.

29:59

And the other little guy was also not that concerned

30:01

about, so I said, you know, what we'll do is we'll

30:03

do a contrast-enhanced ultrasound, and if this

30:06

has a malignant pattern, we'll biopsy it, and if

30:08

not, then we'll know it's a hemangioma and we can

30:10

move on from there and just go to her lung biopsy.

30:13

So they agreed.

30:14

So let me show you these pictures first,

30:16

but this is your echogenic fatty liver.

30:18

Here is the lesion that the

30:19

question is gonna be about.

30:21

So it's hypoechoic there, which hemangiomas can be

30:23

in a fatty liver, but so can malignant lesions.

30:26

This is our arterial phase, and I'll show you.

30:28

Here's the lesion here.

30:30

Here's the lesion here.

30:31

And this little guy, the other little guy

30:32

I was talking about, this is it right out

30:34

here, and I'm gonna show you the delayed.

30:36

This is your delayed phase.

30:37

I do not have this one in the picture.

30:40

If we can bring up the question.

30:41

The question is about this lesion right here.

30:45

Is it benign so we don't biopsy it, or

30:47

is it malignant and we do biopsy it?

30:49

What pattern does it have?

30:53

If we can show the audience response question?

30:56

Perfect.

30:57

So is it a benign pattern, don't biopsy

30:59

it, or is it a malignant pattern?

31:01

Do biopsy it.

31:03

Okay, so this is a tricky one.

31:05

Um, but this one we felt it was read as

31:08

malignant, and I think that it probably is.

31:09

So they're actually coming back for biopsy

31:11

next week 'cause she had some infection

31:13

concerns that we wanna get under control first.

31:15

But, so this lesion right here, it is

31:18

enhancing, it is not super enhancing.

31:20

It's not as enhancing as this one

31:22

is, but I didn't do this case myself.

31:25

So it's entirely possible that we

31:26

missed the very early enhancement.

31:28

But regardless, this is enhancing.

31:30

It is not a cyst.

31:31

We can prove that it is not a hemangioma because if

31:33

it's a hemangioma, it should be filling in, and on the delayed

31:36

phase at three minutes, it's a punched out, washed out.

31:39

So we know it's not a cyst because it enhances here.

31:41

We know it's not a hemangioma because it washed out.

31:44

Um, so that really doesn't leave you much else.

31:47

Um.

31:48

Since it enhanced and it markedly washed out, I

31:50

think this is malignant, and so we're gonna biopsy it.

31:52

So I don't know yet for sure, but that's, I think

31:54

this is worthy of a biopsy at the very least.

31:58

This little guy here, just in contra-

31:59

distinction, arterially enhanced early.

32:01

And I do have another image

32:03

where it's within the field.

32:04

So here is our one that we're gonna biopsy

32:07

just slightly off the edge right here.

32:08

Washed out. This one persisted, this other

32:11

little guy, so I don't know what this is,

32:13

but it's arterial enhancing and persisting.

32:15

So I think it's benign.

32:17

It's probably a flash-filling hemangioma, but

32:19

regardless, it's a benign-appearing lesion.

32:21

Would not biopsy that.

32:22

This is the one we'll target.

32:25

Okay, great.

32:25

So biopsy aids, um, talked a little bit about that.

32:28

This is one more case to show this.

32:30

This was a 65-year-old, questionable

32:32

LRADs 5 lesion on MRI.

32:33

But he actually was a transplanted liver,

32:35

but he got what they thought was probably a

32:37

cirrhotic liver that was transplanted into him.

32:41

So they had this MRI, they got an ultrasound to see

32:43

if we could see it to biopsy that way, and it said

32:46

that it quote unquote, demonstrates the lesion.

32:48

Patient presents for biopsy.

32:49

Here's your MRI, here's your arterial phase.

32:51

It was this lesion.

32:52

I'm concerned, not the easiest one, right?

32:54

It's getting close to the heart and it's

32:56

pretty high up, pretty anterior near the lungs.

32:59

Here's where it was questionable, whether

33:01

it's enhancing right here or not, or

33:03

washing out, I'm not entirely convinced.

33:05

Again, here's your heart nearby.

33:08

This was the ultrasound where they said they saw it.

33:10

And when I took a look at this, 'cause

33:11

it's my biopsy day, I was like, I

33:13

don't think this is the same as this.

33:16

I couldn't figure out any way you could get this

33:18

anterior, nearly peripheral lesion to be this central.

33:22

So I'm like, wait, now we have two lesions.

33:24

What do I biopsy?

33:25

What if this is the cancer and I biopsy this,

33:28

or this was the cancer and I biopsied that.

33:31

So I wasn't sure what to do.

33:32

Neither of them seemed like super easy biopsies.

33:35

So we decided to contrast them and see what they did.

33:38

And that's how we would decide.

33:39

So this is the one of the lesions.

33:41

Turns out this was only visible with a really deep

33:43

breath hold, which is super hard to biopsy that way.

33:45

Biopsy.

33:45

The other one's hard to see.

33:46

But this is the, um, this is the lung right here.

33:49

So it was in this general area.

33:52

And I won't bore you too much with this

33:54

one because not a whole lot happens.

33:55

We were keeping our eye out here.

33:57

This was a little bit of post-surgical

33:59

scarring, most likely. Liver enhances here.

34:02

And unlike some of the other cases that I showed you.

34:04

Nothing really happens.

34:06

So nothing arterially enhanced, nothing washed out.

34:09

So I said, you know what, if I try and biopsy

34:11

this and miss it and it's negative, are

34:13

they gonna send him back for another biopsy

34:15

because they think it's a false negative?

34:17

Um, so with this, I said this isn't worth it.

34:19

There is nothing for me to

34:20

target in this particular area.

34:22

I don't necessarily believe

34:23

that this is, um, a lesion.

34:26

So we also, by, or, uh, enhanced

34:27

the other more central area.

34:30

Here it is right here.

34:31

Again, harder to see on these gray scale images, but

34:33

nothing was happening here in the arterial phase.

34:36

Oops.

34:36

And I'll tell you that nothing

34:37

happened on the washout either.

34:39

So I said these are probably, at least

34:40

this one is a regenerative nodule, and

34:42

there's nothing to do at this point.

34:44

Um, I didn't wanna biopsy.

34:45

I said it'll be a false negative and I could cause

34:47

a complication given where those lesions were.

34:50

So I said they weren't four or

34:51

fives, didn't perform the biopsy.

34:52

He got a bland TACE to further evaluate, just

34:54

to see there was a hypervascular mass somewhere,

34:57

but there was no focal Lipiodol uptake on CT.

35:00

Again, I'm not showing you exactly where the

35:02

lesions are, but that's because the entire

35:03

liver just looked like this, nothing focal,

35:05

and he's been doing well since this point.

35:08

So it can help you from a potentially risky

35:10

biopsy and requesting a repeat biopsy when

35:12

the first one is gonna presumably be negative.

35:15

So moving on to kidneys.

35:17

This is a great article by Barr in Radiology 2014.

35:20

I love this classification system.

35:22

Basically.

35:23

No contrast or few contrast bubbles and septations.

35:26

It's benign.

35:27

If it enhances, it's malignant.

35:29

That's pretty much it.

35:30

Um, caveat is I would not enhance AMLs.

35:33

Um, he can do it — Dr. Barr — and does pretty

35:35

well with it, but the rest of us mortals have

35:37

trouble with those just as you can on CT or MRI

35:40

imaging because AMLs are also gonna enhance.

35:42

I would not advise doing

35:43

these, but here are some cases.

35:46

Here's an indeterminate lesion in

35:47

the kidney, left kidney right here.

35:49

Looks a little hypoechoic.

35:50

So you could recommend an MRI, you could recommend,

35:52

you know, follow up in six months or a year.

35:54

But we contrasted them.

35:56

And again, lesion doesn't

35:57

look great on your gray scale.

35:58

This is a representative image.

36:00

It looked like this the entire

36:01

time during our scanning.

36:02

It never enhanced, never did anything.

36:03

So this is a cyst.

36:05

They don't need a more expensive MRI.

36:06

They don't need to come back for follow-ups.

36:08

This is benign. Period.

36:09

End of story.

36:12

This patient, on the other hand, came in

36:13

with hematuria and acute on chronic renal

36:15

failure, and we found this thing right here.

36:18

And because of a renal failure,

36:19

they didn't want an MRI or a CT.

36:21

So we got a contrast ultrasound.

36:23

And so here's her kidney, here's

36:25

the lesion, maybe some Doppler flow.

36:28

And really hard to see on our gray scale, right?

36:31

But you know, it's right here.

36:32

And again, we're right at our 10 centimeter mark.

36:34

So just to be aware of that.

36:36

And here's a representative

36:37

image of it at two minutes.

36:38

It enhanced a lot earlier as well.

36:39

But here's your lesion, here's

36:41

enhancement, here's your kidney behind it.

36:43

So we have an enhancing mass in the kidney.

36:45

This is a renal cell carcinoma until proven otherwise.

36:47

She ended up getting biopsy

36:48

and ablated at the same point.

36:50

And this was a clear cell RCC.

36:52

So these are much more straightforward cases.

36:54

Kidney lesions.

36:56

This is a 68-year-old male.

36:57

He had acute on chronic renal failure.

36:59

And you can see his kidney itself.

37:00

It's really hard to see, right?

37:01

It's small.

37:02

It's echogenic.

37:03

It's very nodular.

37:04

But he had this right here and

37:06

it kind of looks cystic, right?

37:07

But not quite.

37:08

Meeting all cyst criteria.

37:10

Put some Doppler on it.

37:11

You're like, oh, is that color Doppler flow?

37:13

Or you're like, wait a second.

37:14

There's a lot of red, blue, red, blue, everywhere.

37:17

Is this an artifact kind of

37:18

created by the sonographer?

37:20

And I think this was an image.

37:22

No, it was not done overnight.

37:24

Um, but we, we didn't call the patient back.

37:26

Instead, we called them back for contrast

37:27

ultrasound, and here's your lesion right here.

37:29

In this case, we got it in the point of view of

37:31

his breathing, so you can watch him breathing

37:32

as it goes back and forth, back and forth.

37:34

So we could watch it the whole time.

37:37

Now the bubbles are just

37:39

starting to come into the kidney.

37:44

And then you take a look right

37:45

here, there's our lesion, right?

37:47

There's our lesion.

37:48

It has central enhancement.

37:49

This is a renal cell carcinoma.

37:52

In his case, we don't have path proof because

37:54

it was small and he had a lot of comorbidities.

37:57

So they decided just to do surveillance with

37:59

him, which you can now just do with gray scale

38:00

ultrasound because we've now definitively

38:02

characterized this and didn't have to worry

38:04

about potentially worsening his renal function.

38:07

Okay, so the last section is vascular work.

38:10

So this is a picture of a liver portal vein.

38:12

We saw some echogenic material within it.

38:14

We gave some contrast because that was an

38:16

unexpected finding, and you can see that

38:19

never really fills in this portal vein.

38:21

If you remember some of the other

38:22

pictures, those portal veins are beautiful.

38:24

Don't see anything here, don't see

38:26

anything in a right branch over here,

38:27

either on delayed phase at three minutes.

38:30

Still never filled in.

38:31

So we said this is bland thrombus, it never filled in.

38:34

Got a CT, proves the same thing.

38:36

Here's that branch point thrombus we were looking at.

38:38

So bland thrombus right here.

38:40

On the other hand, this is another patient.

38:43

Big portal vein filled with echogenic material.

38:45

First I saw the same thing, like,

38:46

oh, it's not really enhancing.

38:47

Is this bland?

38:49

Then I realized we were below our

38:50

10 centimeter mark right here.

38:51

So what we did, because he was large and we

38:53

could not get this portal vein any closer, we

38:56

followed this into a more peripheral branch right

38:58

here where we still saw this material within it.

39:01

And now you can see this doesn't look like sort of

39:03

that punched out look or no enhancement that the

39:05

last case, there's all this speckly enhancement.

39:08

This is tumor in vein.

39:09

So we knew there's echogenic material, it's

39:10

thrombus, but now we've proven it's tumor.

39:13

Um, so this was probably an infiltrative cancer and he

39:15

ended up getting an AFP, and it was around 50,000 or so.

39:18

So this is tumor in vein.

39:20

So contrast ultrasound is great at

39:22

differentiating these two, but you can

39:24

do other work, um, that's vascular.

39:26

So moving on to endoleaks for

39:28

abdominal aortic aneurysms.

39:29

About half of people eventually develop one. CTA

39:32

and ultrasound with Doppler, the gold standards.

39:35

Um, and just to quickly review your endoleaks,

39:36

you have your type ones at the end of the grafts,

39:39

type three at the stent graft connections.

39:41

Type four is through the material itself, which

39:43

isn't that common, or type two, which is a

39:45

retrograde flow from the IMA or the lumbar arteries.

39:48

So we can look at this with contrast.

39:50

Ultrasound type one, three, and four are

39:52

all antegrade problems, graft problems.

39:55

So you'd expect that there be synchronous

39:57

enhancement within the sac at the same times

39:59

that the limbs fill, whereas a retrograde type

40:02

two leak, there should be delayed enhancement

40:04

because the limbs will fill first and then it

40:06

takes a while for the IMA or the lumbars to fill.

40:09

So let's see a few quick examples.

40:11

This was a gentleman who had autosomal

40:13

dominant polycystic kidney disease.

40:16

He did get a CTA.

40:17

It showed that the sac had been enlarging and

40:20

they suspected a type two IMA endoleak, this very

40:23

subtle bit right here, but given where it was, they

40:25

couldn't exclude a type three from the left limb.

40:28

They also had a vascular ultrasound,

40:30

which was read as endo present.

40:32

But our CVIR doc took a look at

40:34

this and said, you know what?

40:35

This looks like it's coming from the right limb.

40:38

And since this is a patient with autosomal

40:40

dominant polycystic kidney disease and

40:41

has renal failure, he was trying to decide

40:44

which limb does he interrogate first.

40:46

How much contrast does he need to run to find?

40:49

Is it a type three, is it an IMA, or

40:50

is it coming from the right side?

40:52

Makes a big difference to how he runs

40:54

his procedure when the amount of contrast

40:56

really matters in this particular patient.

40:58

So we did a contrast ultrasound.

40:59

We used the cysts as a window from the kidneys.

41:03

Here is your aortic aneurysm, and here are

41:06

your limbs within the, uh, within the graft.

41:09

So you can already see that these are

41:10

filling, and there's no filling within the

41:13

sac at this point, just within the limbs.

41:15

Great.

41:15

No endoleak so far.

41:16

A few seconds later though, we

41:18

see filling within the sac.

41:19

Again.

41:20

Here is the sac.

41:20

There's filling.

41:21

We now diagnosed an endoleak. It is confirmed.

41:24

So now we have to figure out where is it coming from.

41:27

So two different things we can do.

41:28

This was a delayed at 3:41.

41:29

We see all these bubbles right here.

41:31

I did a flash burst, which is where you give a larger

41:34

MI and you burst all the bubbles within the plane.

41:37

And so that way you can see things

41:39

reperfuse without giving a second dose.

41:40

But when you do that, if you look at the MIs

41:42

right here, you can see the big difference.

41:44

I went from 0.05 to 0.77. You get a beautiful

41:47

ultrasound image, but it only lasts a half a second.

41:50

When we did that, we saw this more

41:52

linear enhancement right here.

41:53

I said, you know what?

41:54

I think this is the source, and

41:56

it's coming from the right.

41:57

So at that point, we stopped.

41:58

We gave a second dose, imaged particularly at

42:01

that area, and we saw on this sagittal plane,

42:03

here's your limb, here's your right limb.

42:05

We saw this coming from behind the limb and

42:08

going this place. We said, you know, this is

42:09

a right-sided lumbar artery type two, which

42:11

was not suspected based off of that CTA.

42:15

And so our interventionalists went up. They

42:16

did a flush catheter and they went up the right

42:19

side and they saw a little bit right here.

42:22

And then a little bit closer, subselecting,

42:24

they found that lumbar artery and they, they

42:26

took that out, and I would argue they gave a

42:28

lot less contrast because they didn't have to

42:30

exclude anything on the left side or an IMA.

42:32

They knew that was the culprit

42:34

based off of our pre-image.

42:36

So last audience response

42:38

question. This is another AAA.

42:39

This was a very large one.

42:42

Two different images.

42:43

So this is within the sac.

42:46

This is a little bit higher up.

42:47

This is a little bit lower down.

42:48

So if we can have the last question.

42:50

The question is, is there an endoleak?

42:52

Just a simple yes or no.

42:54

So this is higher.

42:55

This is lower.

42:57

Alright.

42:58

Excellent.

42:58

We do, right.

43:00

So we don't have any on this

43:01

particular view, but you have it here.

43:03

So the question is, is there, isn't there? This

43:05

isn't diagnosing where. It's just saying that

43:06

there is. And this was a ton. This was a large

43:09

endoleak, and this patient ended up being an IMA.

43:12

Okay, so just a few more

43:14

interesting cases to show you.

43:15

This was a patient with, um, a bleeding

43:18

disorder who had a subcapsular hematoma,

43:20

retroperitoneal hematoma, coming back in follow-up.

43:24

Um, he was—sorry—he was a hemophiliac, so they

43:26

wanted to follow up this subcapsular hematoma.

43:28

And you can see he has a little bit. You can

43:30

see it right here. Not like super suboptimal,

43:32

or is suboptimal imaging, but we contrasted it.

43:35

We put him in transverse. Here's his

43:36

kidney, here's this hypoechoic rind,

43:38

and you can see black hole, right?

43:40

There's nothing—no extravasation.

43:41

It is clearly getting smaller, getting better.

43:43

So you can use this in trauma follow-up,

43:45

particularly in kids who you may not wanna CT again.

43:48

So countless opportunities.

43:49

You can use transplant kidneys where they're

43:51

worried about the renal function post

43:53

ablation to see if there's anything residual

43:55

without getting a three-phase CT scan.

43:57

Trauma follow-ups, peds, which you can also do VCUGs.

44:00

We've done that in adults too.

44:02

Um, MSK, guiding biopsies, vascular work.

44:05

Some people are looking, um,

44:06

at torsion cases for scrotums.

44:08

You can do fertility workups with contrast ultrasound.

44:11

There's a lot of cool things out there, um,

44:13

especially if you can get your clinicians on board.

44:16

So here's some of the references that,

44:17

um, I referred to during the talk.

44:19

They're really fantastic ones.

44:21

And lastly, uh, thank you.

44:23

Um, I have a, we have a few

44:24

minutes left for questions.

44:25

If we don't get to them, you can always

44:27

send me an email, uh, here or you can find

44:29

me on Twitter, so that will open it up.

44:32

Perfect.

44:32

Thank you so much for your time today.

44:34

I wanted to thank all of you for participating

44:35

before we move into the Q&A. And just

44:37

to remind you that it will be made of—this

44:38

conference will be made available on demand on

44:40

MRIlOnline.com, and you can join us tomorrow.

44:43

Dr. Sspa will be with us for a radiological

44:46

assessment of pediatric foot alignment.

44:48

And then Dr. McGillen, if you don't

44:49

mind opening up the Q&A section.

44:51

I do see a few questions in there for you.

44:53

Great.

44:54

Um, so I'll put them right here.

44:56

Um, so the first question is, what is reimbursement

44:58

on average and is it covered by Medicare?

45:01

So, that's a great question and I think it's

45:02

gonna be a little bit different depending

45:03

on insurance coverages and everything.

45:05

And I don't know the exacts, um, but it is covered by

45:07

Medicare, but it is only covered for certain things.

45:09

So at this point it is for lesions only.

45:12

So if you do a liver lesion or a kidney

45:14

lesion, those are covered and reimbursed.

45:16

They're reimbursed at a higher rate than

45:18

a normal gray scale ultrasound would be.

45:20

Um, RVUs also go up as well.

45:22

Um, if you image something, let's say like a

45:25

scrotum because you're trying new and interesting

45:27

things and there's not a lesion, but you're

45:28

looking for torsion, you cannot technically

45:32

bill for that.

45:33

In that case, you can only

45:34

bill for the contrast itself.

45:35

So it is an increase, but it is not,

45:37

um, there's not reimbursement on that.

45:40

Um, as to how much contrast is, I honestly

45:43

don't know that because I'm not at all involved.

45:46

So I would say I believe it's around a hundred

45:50

dollars per vial for Lumason, but it's also, I

45:52

think, gonna depend on the institution you're at.

45:54

But that's around what Lumason is in general.

45:58

Okay.

45:58

Next question is, let's see.

46:02

Are the subtraction images automatically

46:04

buddied with the gray scale?

46:05

So I'll start with that.

46:06

Yes.

46:06

Yes, they are.

46:07

So when you wanna watch somebody breathe,

46:09

um, you can look for that, the lesion,

46:11

especially when they're small coming in or

46:13

coming out, that can absolutely help you.

46:15

Sometimes it's so fast on the ultrasound screen

46:17

in the room that I can't see it, but as long as

46:19

I captured all those pictures, I'll go back into

46:20

the reading room, look at them much more slowly,

46:23

and they, they do come together at all times.

46:25

They, they move together.

46:26

So that's great.

46:27

Um, oh wait, that was only part of the question.

46:30

Let me go back to that.

46:33

Um, it's still there.

46:34

It's just one down.

46:35

It's one down.

46:37

Okay.

46:38

Um, oh, there it is.

46:39

Is the post-process after you've completed the scan.

46:41

Oh, okay.

46:42

And do techs perform this nowadays?

46:43

Radiologist only.

46:44

Okay.

46:45

So it's there in the room as well, because

46:46

otherwise you can't see the lesion necessarily.

46:50

Um, so it is not a post-processing.

46:51

It's available instantaneously.

46:53

Um, at my institution, the techs

46:55

don't do these by themselves.

46:56

We do have a radiologist.

46:57

Sometimes we'll do a resident in, um, you

47:00

could technically do them with, you know,

47:02

either two techs or a nurse and a tech.

47:04

But to scan and to inject the contrast at

47:07

the same time, it needs to be two people.

47:09

It cannot be one person.

47:11

It's just not physically possible.

47:13

So if you train your techs and you have

47:15

like a protocolized image and you feel

47:16

very comfortable, especially, you know.

47:18

Say renal lesions, um, you could

47:20

have techs, two techs do them.

47:22

Uh, right now we still always have a

47:24

radiologist because we're on the newer side

47:26

and we don't have enough techs to spare.

47:28

Okay.

47:29

Next question.

47:29

Can contrast ultrasound be safely used in

47:31

pediatric patients and pregnant females?

47:34

If yes, do we need any blood in, uh,

47:35

investigations or pre-procedure evaluation?

47:37

So for pediatric patients, yes.

47:40

It is actually FDA approved, um, for VCUGs.

47:44

Um.

47:45

In the pediatric population.

47:46

So that is absolutely approved.

47:48

They do have a reduced dose.

47:49

I don't generally do peds, so I don't have

47:52

the dose memorized, but it is a per weight,

47:54

just like most pediatric medications.

47:56

So it's absolutely safe to use in pediatrics

47:58

for lesions as well, and not just VCUGs.

48:00

Um, but for lesion evaluation pre-

48:02

or pre-biopsy type stuff, pregnant

48:05

females is a completely different story.

48:07

Um, it is not approved for their use.

48:10

Um, as far as I know, I've talked to a bunch

48:14

of different people who do contrast and who do

48:15

a lot of contrast ultrasound, and none of them

48:18

have ever done a pregnant female. Theoretically,

48:21

it might be safe.

48:22

Um, I hear that there were some studies done, I

48:24

believe in Europe on twin-to-twin transfusions, which

48:28

would suggest that it's safe, but since it hasn't

48:30

been proven and there'd, you know, be a high low

48:33

risk in the sense probably nothing would happen.

48:34

But if something did, it's catastrophic.

48:36

Uh, I don't think anybody in the US

48:38

actually does them in pregnant females.

48:40

No procedure evaluation for, um,

48:42

pediatric patients. Just need their dose

48:44

or their weight to dose it appropriately.

48:47

Okay.

48:48

Next question is what timing

48:49

do you look for tumor thrombus?

48:52

Great question.

48:53

So that case that I showed you is actually the

48:55

only one I've seen so far for tumor thrombus.

48:57

Um, it's not that common, um, at least in my practice.

49:02

So that was the only one that I have.

49:03

And in that case, um, it's, it's really

49:06

just like an arterial, it should act because

49:08

right, if there's tumor in the vein,

49:09

it should still be fed by the artery.

49:11

So technically it should arterial enhance

49:13

and kind of wash out a little bit later.

49:15

I find that really hard to judge when you're

49:17

judging something that's in a portal vein.

49:19

Um, so basically it's almost like you have to

49:22

think backwards for a tumor thrombus, because if

49:25

there is any enhancement, then it is tumor thrombus.

49:28

If it is a bland thrombus,

49:29

there will be no enhancement.

49:30

So that's simple and easy.

49:31

So if you do see enhancement, that means it's tumor.

49:34

The next question is, of course, you

49:36

know, how can you tell tumor thrombus

49:37

from just regular portal vein flow?

49:39

And in that case, it's off

49:41

of your gray scale, your pre-

49:42

imaging. All of the cases where I've

49:44

found thrombus, whether tumor or bland,

49:47

we had a suspicion on the gray scale that there

49:49

was something echogenic in that portal vein.

49:51

And so that's when you go down that tree.

49:53

If I don't think anything's in there, I don't

49:55

think there's gonna be tumor thrombus either.

49:57

Um, and so far I haven't been wrong, so

50:01

keep my finger—knock on wood—for that one.

50:03

But that's how you would look for it.

50:04

So you can look for timing, but again, it

50:06

really just doesn't enhance or does it not.

50:09

Okay.

50:09

Next question.

50:11

Do you have any experience, thoughts on use

50:12

of contrast ultrasound in characterizing

50:15

indeterminate testicular lesions?

50:17

Great questions.

50:17

So I have no experience on it.

50:22

This is one of the areas which I think

50:23

would be really interesting to look at.

50:27

Um, in my experience, most testicular lesions

50:30

that are, you know, solid type lesion end

50:32

up coming out anyway, or they have a known

50:34

lymphoma or lung cancer type diagnosis.

50:36

So does enhancement or not really truly help?

50:40

Um, probably not.

50:42

There are those few indeterminate ones and I

50:44

think unfortunately they're so rare that we don't

50:46

have any answer out there in the literature yet.

50:48

But I think that would be super interesting to

50:50

see what they do and, you know, kind of follow

50:52

them short intervals and see, do they grow, do

50:54

they continue to enhance when they come out?

50:55

I have no experience in it yet, but I

50:57

think it's super interesting, would be

50:58

a really exciting thing to do with this.

51:01

Okay.

51:01

And that was just not a question, but a thank you.

51:04

Okay.

51:04

How do you approach polycystic kidneys

51:07

looking at complex cysts with solid components?

51:09

Great question.

51:10

Um, polycystic kidneys I feel like are the

51:12

bane of a lot of radiologists’ existence when

51:15

we're looking, um, to find the rare cancer

51:19

that's in them. You know, increased risk of

51:20

cancer, but still not that common, right?

51:22

And then they have all of

51:23

these variable density cysts.

51:25

A lot of times they can't get contrast

51:27

anyway, and so it can be really challenging.

51:30

Um, I think contrast ultrasound is

51:31

probably a really good modality for that.

51:33

If you can see all of the kidneys, and

51:35

that's, that's the hardest part, right?

51:36

'Cause they're huge kidneys, so you need to feel

51:39

confident that you have a window to see all of them.

51:41

It's not gonna be easy to compare to

51:43

priors, but you can look for enhancement.

51:44

I think it.

51:45

I think it would be a very reasonable way to do it.

51:48

Um, complex cyst with solid components.

51:50

Contrast ultrasound is great for that.

51:52

I didn't show you a case, but I

51:54

have one, um, in a youngish guy.

51:57

He is in his thirties and it looked like it was

51:58

probably gonna be a cyst, but we enhanced it anyway.

52:01

And he had this tiny little nodule in the back of

52:03

it and this weird rim enhancement that I honestly

52:05

would've called a cyst remote, like a complex cyst.

52:08

But it enhanced and it ended up, he went to surgery.

52:10

It was a clear cell carcinoma.

52:11

So contrast ultrasound is great for complex cysts

52:14

with solid components, like absolutely fantastic.

52:17

The, um, the subtraction type of imaging

52:19

that you get with it is just wonderful.

52:21

It's super helpful.

52:22

I definitely recommend it.

52:25

Okay.

52:25

Can you please revise some again for tubal patency?

52:29

I'm not entirely sure what that means, but if

52:32

we're talking about tubal patency for, um, like

52:34

infertility workups, I have not done them myself.

52:37

Um.

52:38

But a colleague at Einstein in Philadelphia does them.

52:41

Um, and what she does is she does a 3D ultrasound

52:44

to look at the uterus for anomalies and then

52:47

injects to look at the, um, like the endometrial,

52:50

not the endometrial line, but the shape of the

52:52

cavity, and then again injects it by hand, not IV.

52:56

Um, and then looks to see for fallopian tube

52:58

patency, to see if there's spill on either side.

52:59

The pictures I've seen are absolutely gorgeous.

53:02

That one, of course, requires buy-in from your OB-GYN

53:05

colleagues 'cause they're going to send you these

53:07

patients, but the images are absolutely gorgeous.

53:10

No radiation with this whatsoever, safe way to do it.

53:12

So I don't have any images of that to show

53:14

you, but it's really cool what they're doing.

53:16

Okay.

53:17

Next question.

53:17

After injecting contrast, how long do

53:19

you wait until you can do ultrasound?

53:21

Sure.

53:22

So in the beginning we would, I would inject

53:24

and then we would image the whole time.

53:25

And then sometimes it would take up

53:27

to 30 seconds to reach whatever organ.

53:29

And that was right when our timer stopped,

53:30

so we would miss the arterial phase.

53:32

So now that I'm a little bit more comfortable with

53:34

this, uh, I wait until we see the first few bubbles.

53:37

So I tell the sonographer when I'm injecting,

53:39

I tell them when I'm flushing, when I flush.

53:41

That's usually when they start the counter, but

53:43

they don't actually start the imaging itself

53:45

until they start seeing those first few bubbles,

53:48

um, because nothing's gonna happen before then.

53:49

And other than that, you're just creating more

53:51

images that you have to look through later.

53:53

Um, so everyone's different.

53:55

I find sometimes it takes as long as 30

53:56

seconds for the contrast to get to them.

53:58

Sometimes it shows up, you know,

53:59

five seconds after I've injected it.

54:01

But those first few bubbles are

54:02

usually my marker for starting.

54:05

Uh, so I don't, I don't have any images for

54:07

tubal patency, which is the next question,

54:09

um, because I have not done that myself.

54:11

Um, I'm not sure if they're in the literature at all.

54:14

Um, but I, I do know one person

54:16

doing, and they were cool pictures.

54:19

Uh, another lecture related to fertility workups.

54:22

So I don't do those with contrast ultrasound,

54:25

but if, um, people want that, I can suggest a

54:28

person who has done 'em and has pictures,

54:30

um, I can refer to that colleague as well.

54:33

Um, what's the role in tub-

54:35

-ency evaluation?

54:37

Sure.

54:37

So you can do it.

54:39

Um, again, I don't think it's been

54:40

published online as far as I've known.

54:42

I've not done a recent literature search.

54:44

Um, but it would work just like, um, like

54:47

you would do it under fluoroscopy, right?

54:49

You canalize the same way the cervix,

54:50

you inject a little bit of contrast.

54:52

You fill, um, the uterine cavity itself, and then you

54:56

look for spillage on either side, and that's just by

54:58

injecting fluid and kind of pushing it out, right?

55:00

So you can actually see the fallopian tubes

55:02

and you see the same kind of picture you

55:03

do as the contrast surrounds the ovaries.

55:06

So again, trying to paint a,

55:07

a sort of picture for you.

55:08

Um, but you can see if there's patency or not.

55:11

You can then see if a tube is

55:12

dilated, um, and things like that.

55:14

So it absolutely can be done.

55:16

You can, you know, tilt the patient a

55:17

little bit to try and help with that, but

55:19

it can be done similar to fluoroscopy.

55:23

Okay.

55:23

Recap on the type of endoleaks.

55:26

Sure.

55:26

So what I'll do, rather than just recapping

55:27

'em too much, I'm just gonna go backwards.

55:29

Sorry if I make anyone dizzy.

55:30

Here's the picture.

55:31

This is from JUM, um, Ultrasound Quarterly,

55:34

which I think was a nice example of these.

55:36

So these are the types of endo-

55:38

leaks that you have right here.

55:41

And what's really most important is

55:44

figuring out where it's coming from.

55:45

Sorry, I have kids in the background.

55:47

Um, but the antegrade, so the one,

55:49

three, and four is a graft problem.

55:51

So you get synchronous enhancement.

55:53

Type two endoleak are retrograde problem.

55:55

So you get delayed enhancement.

55:57

There's no literature saying exactly

55:59

what delayed means versus synchronous.

56:02

Um, it really depends on how

56:04

forceful that endoleak is.

56:05

If it's really just a slow, gradual leak or if it's

56:07

really under a lot of pressure, you know, so it can

56:09

show up, you know, five seconds might be the delayed.

56:11

It can be up to like 20 or 30 different seconds.

56:14

So this one's gonna depend on the degree.

56:19

Okay, next question.

56:19

Is there a role in differentiating testicular

56:22

lesions, malignant versus benign?

56:24

Uh, I don't know of anyone doing that.

56:26

I think that you could, and I

56:27

think that would be interesting.

56:29

Usually you wouldn't need it necessarily because

56:31

a lot of the benign testicular lesions, you know,

56:34

might be calcified or, you know, are fairly already

56:36

well-defined epidermoids, that kind of thing.

56:39

But if you did have an indeterminate one,

56:40

again, I think that would be an interesting

56:43

role rather than just getting, you know, a

56:44

three-month follow-up or urology consult.

56:47

I do think there would be, but I don't think

56:49

it's been studied yet, so we don't know exactly

56:51

what we're looking for for these indeterminate ones.

56:54

Okay.

56:55

Um, can you—I'm sorry.

56:57

Do you perform ultrasound for vascular patency on post-

56:59

liver transplant patients, e.g., hepatic arterial flow?

57:02

Um, I have done it on one because the,

57:04

there was a duplex ultrasound that they

57:06

weren't sure whether it was patent.

57:07

We have a different vascular ultrasound lab.

57:09

It is not our radiology department.

57:11

Um, so they just wanted to know

57:12

was it patent or was it not?

57:13

And so we were able to answer

57:15

that question for the most part.

57:17

Um, the limiting factor is

57:19

going to be the depth, right?

57:20

If these are larger patients, if they're

57:21

larger livers, you are not going to be

57:24

able to necessarily see, you know, the

57:25

hepatic artery from where its take-off.

57:27

You're going to see it in the liver,

57:28

you're gonna see it in the hilar area.

57:31

So you may be able to answer this, but if it's really

57:33

a very more peripheral portion, you may just not

57:35

see it unless you have one of the newest, um, newest

57:38

machines and platforms, which are really super cool.

57:41

Um, but we have done it.

57:42

You absolutely can do it.

57:43

And you can do it for things like if you had

57:44

a pseudoaneurysm or you were worried about

57:46

that, you can image pseudoaneurysms just

57:48

like you would a post-transplant liver.

57:51

So definitely a very good use for it.

57:54

Okay.

57:55

And.

57:57

Okay.

57:57

Tubal patency question again. Again, it

57:59

doesn't have a defined role, but people are doing it.

58:02

So I think, you know, if that starts

58:03

getting published and getting out there,

58:04

I think it could have a role in that.

58:06

And I think it's great because it's no radiation.

58:08

Um, but we're not, it's, I

58:10

don't think it's out there yet.

58:11

Um, and very, you know, broadly used at this point.

58:15

Okay, what is the frequency of the

58:16

probe that can be used in contrast?

58:17

Great.

58:18

So again, it's gonna depend a little bit

58:19

on your system and your system settings.

58:22

So in some of the newer ones, every single probe,

58:24

including a transvaginal, can do contrast ultrasound.

58:27

So if you're gonna buy one of these, I would recommend

58:29

making sure your system can use any kind of probe.

58:31

You can use the nonlinear for peds or cardiac applications.

58:34

The one caveat is if you are using a higher

58:37

frequency probe like a 9 linear, you will

58:39

usually have to double your contrast dose.

58:42

So often that is not a problem, um,

58:44

but you do have to be aware of it.

58:45

I have messed around with a kidney lesion

58:47

just to see if that was really true.

58:49

Uh, and it was, 'cause I did a regular dose

58:51

the first time with a deeper probe, used a

58:53

superficial and I could not see very much at all.

58:55

So you really do need to double your dose.

58:59

Okay.

58:59

Is there a role for contrast ultrasound,

59:01

early rejection of transplant kidney?

59:03

Um, that's a yes and a no type of question.

59:06

It's not going to tell you that

59:07

it's rejecting necessarily.

59:09

You're gonna see like a parenchymal problem,

59:10

but you might be able to catch either the

59:12

vascular problem if there's a, you know,

59:14

something wrong with the artery or the vein, or

59:16

it will show you if there's altered perfusion

59:19

potentially because of an artery or vein problem.

59:21

So.

59:22

I think that there has been some use of it.

59:24

There is some literature out there, I think it's

59:26

mostly out of Europe, um, that they've done this

59:29

in the past again, and they've been doing contrast

59:30

a lot longer than it was approved in the US.

59:32

I think it's only been approved since

59:33

2016, so we're a little bit behind on that.

59:36

Um, Southeast Asia also has a

59:38

lot of work on this as well.

59:40

Um, so it is possible, so you could look for. It

59:42

wouldn't be rejection per se, but it would exclude

59:44

other things like, you know, is there a hematoma,

59:45

is there active extravasation, is there a hematoma?

59:48

That kind of things.

59:49

That's what it's really used for, useful

59:51

for in the early phase of a transplant,

59:53

kidney, pyelonephritis, that kind of thing.

59:56

Um, excluding those other things

59:57

as the cause of the rejection.

60:00

Okay, role of contrast-enhanced ultrasound.

60:02

Endometriosis.

60:03

Oh, great question.

60:04

Uh, my other thing that I

60:05

really like is endometriosis.

60:07

Um, sorry, I have a kid screaming in the background.

60:10

Um, the role of contrast ultrasound—

60:12

that I have not seen published anywhere, um,

60:15

it's something we're thinking about doing,

60:16

but it depends on your endometriosis, right?

60:19

If you have the deep infiltrating

60:20

type, that is a fibrotic process, so

60:23

that theoretically should not enhance.

60:26

But what it would show is that the endometriosis,

60:30

um, does not enhance while, you know, say the bowel

60:32

that it's on or the ligament that it's adjacent to

60:35

does enhance, and it might make it show up brighter.

60:37

So the endometriosis itself does not enhance.

60:40

Or should not really enhance.

60:41

Theoretically, I think the things around it

60:44

will, which may make it show up and prove

60:46

that it's not just like a folded loop of

60:47

colon, but that it truly is an endometriosis

60:50

deposit on the colon, that kind of thing.

60:52

But I don't think that's been studied.

60:54

Um, so I think that's another interesting thing to

60:56

try, especially now that transvaginal probes, um,

60:59

for most systems do have contrast software on it.

61:03

Okay.

61:03

Adverse effects of contrast-enhanced

61:05

ultrasound in chronic kidney disease?

61:07

None.

61:07

And that's part of the beauty of this and why,

61:09

um, our hepatologists have really gotten on

61:11

board with this, because a lot of their patients

61:13

do have chronic kidney disease. Doesn't affect

61:15

the kidneys at all, because it's intravascular.

61:17

So they don't excrete it whatsoever.

61:19

It just stays intravascular within the blood pool the

61:22

entire time until the little bubbles rupture, and

61:25

then you actually breathe out the byproducts.

61:28

That's how your body gets rid of 'em.

61:30

So it is not excreted through the kidneys.

61:32

It does not affect them negatively in any which way.

61:35

So that's what it is, what's one of the, uh,

61:37

the really cool things—one of the only contrasts

61:39

that can do that. No kidney problems whatsoever.

61:41

So that never, you never have to

61:43

check labs, anything like that.

61:45

Okay.

61:46

And then what could the future

61:47

role be in characterization of thyroid

61:49

lesions, benign versus malignant?

61:50

Um, good question.

61:52

I think that there might be some literature

61:53

on this. I'm not a hundred percent sure. Um,

61:56

theoretically, in my head with this, um, is that—

62:02

we know that there are thyroid lesions with

62:03

Doppler, color Doppler, and we know that there is

62:06

a higher rate of malignancy in those, but we also

62:08

know a lot of benign ones also rapidly enhance.

62:12

So just enhancement alone if we contrasted them,

62:14

I don't think would be really helpful, because

62:16

I think both benign and malignant enhance.

62:18

I don't think it's specific

62:19

enough, um, to differentiate.

62:21

Um, could there be a pattern, kind of

62:23

like how we talked about in the liver?

62:24

That, I don't know.

62:26

That's a good question, and I don't know if it's

62:27

been studied, so I'll have to look into that

62:29

myself as well to see if it's already out there.

62:32

Um, but it would really have to be

62:34

a pattern differentiation, because

62:35

I think both types would enhance.

62:38

Okay.

62:38

And then any role in breast ultrasound?

62:40

So, caveat, I'm not a breast, um, person.

62:43

I don't read them.

62:44

I don't perform those kind of biopsies, so I,

62:46

I'm not that familiar with their literature.

62:49

That being said, I personally think

62:51

this would be a great utility for it.

62:53

Um.

62:55

A lot of the information it can show

62:56

you is similar to MRI in other lesions.

62:58

You know, is there enhancement?

62:59

Is there not? Enhancement patterns and such forth.

63:01

So I think it could be really useful in breast.

63:04

Um, I believe some people are studying that.

63:07

Again, I've not done any deep dive

63:09

into the literature in that whatsoever.

63:11

Um, our breast, um, images use a different

63:15

machine that does not have contrast.

63:16

So I've not approached them on that, which is

63:18

another reason I just haven't looked into it.

63:20

I think that there could be, and I think

63:21

it could be a really interesting, um, way

63:24

to use contrast ultrasound in the breast.

63:27

Um, again, no radiation type things.

63:29

Not that you use radiation much in breast

63:31

imaging anyway unless you're being treated, but

63:33

I think it's just another safe way, um, that you

63:36

could potentially kind of guide your biopsies.

63:38

But again, I'd have to do a deeper dive.

63:39

I don't know if benign things like fibroadenomas

63:41

enhance, that kind of stuff, but I think that would

63:43

be a really interesting, um, question to look into.

63:49

Okay.

63:50

Perfect.

63:50

I think that's all the questions.

63:52

I bring this to a close.

63:52

I wanna thank you, Dr. McGillen, for your

63:54

time today, and thanks to all of you for