Difficult Carotid Cases - HD

Introduction

If these are too simple, I apologize.

And if they're too hard, I apologize.

And thank you so much SRU for having me.

Thank you for staying till the end of the day.

Appreciate it. And let's,

when I look at a case, I go through a pattern, a similar

protocol, which is to look at the quality

is everything on there.

I look at the waveform shapes.

I look for symmetry between the two sides, recognizing

that the vertebral artery may be asymmetrical.

And then I look at the numbers.

The numbers are really, a part of it, but

because Leslie spoke earlier on, all the other stuff

that didn't involve,

numbers,

we're gonna be a little bit

number centric for some of these cases.

And for others, ones we won't.

Stenosis Assessment

When I look at a stenosis,

I require my stenographers

to record three distinct parts of the stenosis.

Most of you are interested in what's happening

inside the stenosis with the highest velocity jet,

and that's okay, but that velocity has to be

with respect to something.

We don't want to wanna get away form before the stenosis.

And the carotid, typically

that's in the common credit artery just

before the bifurcation.

And where the common credit artery walls are parallel

before the bulb forms.

And then we look beyond that over several centimeters

to look for turbulence.

Because excessive turbulence is one of the things

that we look for to tell us that there's pressure reduction.

Pressure turbulence is one of the things that cause

stenosis,

indicates that stenosis is pressure reducing.

Here's a waveform gray scale color and spectral doppler.

The other thing is we have feast three modalities.

We wanna make sure that they're concordant with one another.

And any time you have discordance between them, you have

to explain what that's about.

And you may need to scan more, you may need

to think harder or you may need to give up.

Those are your options. Okay?

If you're lucky enough,

when you look beyond,

you'll see some evidence of turbulence.

And you've seen some examples there in the course of the,

of the, the conference so far with two

and fro simultaneous flow, simultaneous forward

and reverse flow, which is the material twirling around.

You can see some linear,

some lines sometimes on the waveform, probably related

to vortex shedding.

And then if you're in carotids, we don't usually do this,

but in other vessels like renal arteries, we can look

for distal to look for very,

low pressure downstream.

Again, that usually is evidenced by the tus parvis waveform,

which has either a slow time to upstroke the tar,

the TTUs part, or too much diastolic flow

because the pressure difference between systole are similar.

You get low,

lots of diastolic flow

with a slow upstroke.

This is your tardis parvis waveform.

And I'm trying to heal, cure my dyslexia for years.

I say parvis tardis 'cause that's what it sounds like to me,

but I'm trying to turn it around.

And John reminds me that this looks like a tp.

Remember Tardis, tardis. So there you go. Okay.

Criteria for Degrees of Stenosis

There are a bunch of criteria that we use for degrees

of stenosis, and I just want to kind of pitch

to you two things.

One is, I am a strong believer in high grade stenosis.

Criteria should use end diastole.

And what happens in a stenosis is that you have narrowing

and you have a pressure gradient.

And that pressure gradient is most profound during systole.

But when you get worse stenosis,

you have a pressure gradient during diastole and systole.

And as Bern nearly taught us,

when you have a pressure gradient, you have high velocity.

The presence of high velocity during diastole is,

related to more severe stenosis.

It's a more specific sign for high grade stenosis,

typically in the 70 to 99 range,

which is the more severe range by nasa.

Okay? Now, usually try to talk to you

and give you one thing to think about for next year.

And the thing I want you to think about has to do

with these high velocity waveforms.

And, here we here we see lots

of systole and lots of diastole, okay?

Is this related to resistance?

We've always seen lots of diastolic flow.

The diastolic flow here is 130 centimeters per second,

very high diastolic flow.

Does it make sense to call this a low resistance waveform?

And I'm not gonna answer it,

and I know Leslie's gonna ask me later,

but I'm not answering it.

Okay? As a rule, some

of us use internal criteria, some of us use other criteria.

This is from ED Grant. Most people use the primary parameter

of peak systolic velocity.

Others use combinations with ratios and within diastole.

These are the numbers from the SRU consensus conference.

And for the, for the point of today,

we're gonna use these numbers even though I might not use

exactly these numbers in my own lab, okay?

Difficult Cases

I've been asked to talk about difficult cases.

Let's go and show some difficult cases,

and here's a list of what makes things difficult.

You're gonna see examples of all these as we go through.

I'm not gonna try to tell you.

The Case of the Late Stenosis

Let's start with the case of the late stenosis.

Okay? Here's a patient.

You can see the common credit artery.

Here's the carotid

bulb

and the proximal internal credit artery looks pretty good.

And then as we get this way, it looks a little funky here.

Here's a, a blow up of this vessel.

Again, this is nowhere near the,

the proximal internal credit artery.

You can see these,

echogenic lines

that are sitting inside of it.

Those are associated with higher velocity.

The vessel is straight, but this alias in here, which means

that the velocity has gone up through that region.

Here in the common credit artery, the velocity is 69

in the proximal internal car artery

where there's no narrowing, it's 59.

And here in the region of interest it's 223.

And as we go beyond it, as we profile it, it drops off

to 125.

Okay? Here's the picture that everybody's interested in.

223 centimeters per second in a funny place.

Any thoughts? This one I'll give you free.

The first one I'll give you,

this is not in the right place.

Here's a stenosis in an area that's not supposed

to be stenosis atherosclerosis typically

involves the first few centimeters.

This is a case of fibromuscular dysplasia

and, pretty straightforward, nice example of it.

Okay, couple of pitfalls though.

The distal internal corona artery, as it turns away,

can frequently be a little bit higher.

Normally you get in a normal ICA,

something like 80 60, 80,

but when you get to the distal, it may go up to a hundred,

120, and it may even go to 130.

Again, not un uncommon.

Again, they're not associated

with downstream turbulence from that,

and they're not associated with abnormalities.

It's related to the fact

that the vessel is diving away from us.

It's curving a little bit, and a few things are going on.

The criteria that grant,

the NASA criteria are really only good

for the first use centimeters.

The fact that something is higher

to 130 doesn't mean you call it a stenosis,

but when you see very high velocities with breweries

and with the suggestive symptoms,

which may be cerebrovascular symptoms,

or the patient hears a brewery in their, in their ear,

which is very typical of FMD,

you should be thinking about FMD.

Okay? The thing I want to talk to you about, the thing

that's difficult is most of us want to grade FMD

and the current recommendations by the,

FMD committee is you don't,

you just say FMD is present from

a point of view description.

It either has one focal area of FMD

or there can be a multiple area of FMD.

Their description is focal or multifocal.

In this case, there are multiple webs, and

therefore it's multifocal FMD.

Also remember that FMD frequently

involves multiple circulations.

When you find FMD or suspect FMT, you want to confirm it.

We typically do that with a kind of total body,

CTA.

We go from the, basically from the head,

all the way down to the,

femorals.

The Case of the Meandering Vessel

Next case, the case of the meandering vessel.

This is a patient who has

sigmoid icas.

The proximal icas are not, not in either of these pictures,

is kind of the mid to distal,

icas.

Okay? That's the first piece of information.

Everybody recognize

that I'm gonna need some feedback from you guys here.

It's almost time. And you know,

you're probably all drooling at this point, you know,

and falling asleep, but I kind of need you awake

to give me some positive feedback here.

Does anybody, everybody sees the sigmoid shapes? Yes. Okay.

Did everybody notice the age of the patient? Yes.

Does anybody have a diagnosis for me? Pardon?

Tissue? Like a Los Danlos? It's close.

There's something wrong with these vessels,

but it is FMD.

FMD is associated with, with the sigmoid shape,

particularly in young patients.

FMD is being seen in older and older people,

but when you get people who are not in the atherosclerotic

range, this is, and why is this important?

This is not a narrowing, this is not a stenotic lesion.

These are just sigmoid shapes.

The point of,

FMD is that you're associated also

with aneurysms and other areas such as renal, FMD.

You want to treat this patient with a diagnostic CT scan

to exclude,

intracranial aneurysms as well

as other sites of FMD,

curves will ex, the velocity will accelerate around curves.

You have to be careful, be careful about colon stenosis

frequently, it's just the fact that there's acceleration

and elongation is not,

is very,

very common in older patients.

When I see this in the elderly population,

which I'm getting to moment by moment,

then I would probably not worry about FMD

and just were recognize

that it's just the vessels elongating as time goes on.

Sonographer-Related Challenges

Part of what I decided to talk

to you about were difficult cases,

but part of what makes ultrasound difficult is that you,

you rely in total or in part on the sonographer

and the vascular text giving you good information.

We're gonna show some cases today where the sonographer

is new, the sonographer is

old, and maybe a few where the sonographer is in between.

All right? Most of you who have sonographers

of a certain age, they have told you that, you know,

they've been doing this for the last 40 years.

And who are you to tell them that you're doing it wrong

or, you know, they just have their way of doing it.

I'm sure that Mary Fredy is here, right?

That doesn't happen at the Brigham,

but it happens that places like my place.

Okay? This is a pay.

The other thing is that it's, it's, what's happening

to me is we're getting more and more hospitals, right?

We're inheriting all these hospitals.

We had a re of people we trained

and now I get, who knows?

I actually, it's really funny, one of the hospitals

that associated with us have four stenographers

that we refuse to, to,

hire.

Be careful what you wish for.

It may come back to what you, okay.

These mergers are not always fun, right? Okay.

Hopefully you were looking at this. This is a right side.

The, the common credit is here with this waveform.

And here the films that we were given,

here's the external credit artery here

with an angle corrector here,

and the waveform looks like that.

And here's the external again, with another waveform.

Looks like that. And a couple of pictures

of the ICA proximally and distally.

That's, that's what's labeled internal credit artery.

And the waveforms look like this.

Any problems here with anybody?

Anybody have any problems? Pardon?

Those are the Internals.

The internals look like the external.

Yeah, the big vessel kind of looks like a external crowded,

and the little vessel looks like, I'm sorry,

is labeled external and the switch.

They're switch, I thought.

I called her up and she goes,

and then I said, would you, so then I had to beg, you know,

it's because you only think

that you're in charge of anything.

And so,

here's the, what's labeled internal

and external and is Cliff pointed out there's two little

diastolic flow on the, the,

the image on the left

and too much diastolic flow on the image on the right.

Okay, so they're bigger.

I well, okay, so,

technically inadequate.

Do it again. So here are the new pictures.

I got a phone call saying, wow, Dr.

Needleman, you were right, Cliff, you were right.

She decided that this was the internal creditor

and now she actually found a branch coming off here.

If you look for it, if you train your sonographers

to look for branches on the external, they will find it.

Okay? Here we found it

and she redid the, this is the new ICA,

which looks more like an ICA

and here's the new ECA, which looks more like the ECA

and life was good.

Anybody notice anything else that was a problem?

Bad angle correction, bad angle correction.

This is a very smart group.

Okay,

listening

To you for years, Pardon me?

Listening to you for

Years. Yes.

This, I then said, you know,

I mentioned it when we talked about the first set of images,

but that was a little bit too much for her to handle.

She was able to get the IC EC part.

We have to save that,

that conversation about angles a little bit, right?

Let's have a word about angles as we do this, right?

Most of us, not everybody,

but I align the angle parallel to the walls

because you can always see the walls.

Some people align the angle cursor

with respect to the color.

And I'm not gonna get into that battle today,

but we do it this way and we try

to keep an angle which is appropriate.

As you start getting too high angles,

you start introducing error.

If you, we want to do

below 60 and we try to scan everybody's carotid

to 60 to be consistent.

The, the recommendations are to keep below 60

and never use a number if it's below, above 70.

What this sonographer has been doing her whole career is

that she's been setting the machine for 60 degrees

or in 55 in this particular case.

She's scanning at 60 degrees irrespective of

where the angle is.

If you think this isn't gonna happen

to you, it's gonna happen to you, okay?

It happened to me. Now you have to kind of explain this.

I had one other sonographer case I didn't show you

today, who swore.

She goes, I've been an RVT for 14 years

and no one has ever told me that I'm using the wrong angle.

I said, I absolutely believe

that nobody's ever told you that.

The Case of the Contralateral High-Grade Stenosis

The case of the contralateral chlorate

or also known as the case of the contralateral conundrum.

Okay? I'm gonna do the left side first.

Usually I do, we just scan right side first

and left side second because it's the way we do it.

But this, I'm gonna show you out of order.

Here's a carotid, it's got a big plaque

that's got calcification in it.

There's some narrowing in it, there's some aliasing in it,

there's a lot of aliasing.

The velocity here is 92, then,

in this vessel is 3 43 with an L and diastolic velocity 149.

Really an easy diagnosis I think for everybody.

Here's the downstream turbulence.

It's got all the criteria,

and then as it goes down,

the velocity heads back down to 118.

It's got all the, all the goods we need

for calling this a 70 to 99% stenosis, right?

Everybody, anybody have a problem with that? Okay?

The problem for me is the other side,

here's the common credit artery

and the proximal internal credit artery.

Here's the color. There's a little bit of the, a little bit

of,

vortex shedding over here,

but I want to just point out what the column

of color looks like.

Here's waveform 90.7 200, 214.

We're looking around for the highest velocity

as we go downstream 159.

And then as we go further downstream a hundred, okay,

we have a velocity change.

Everybody with me? Okay?

The big question is

what do we do now we had a high grade stenosis on one side

and we have this on the other side.

Alright, what do people want to call the right side?

How many people wanna call it normal?

How many want people want to call it above 70%?

How many people wanna call it 50 to 69%?

How many people wanna call less than 50%? Really? Jeepers.

This is a really smart group. Okay?

What everybody knows here is

that when you have a high grade stenosis

or an occlusion on one side, the brain gets its flow,

it's autoregulated,

it's gotta get its flow one way or the other.

If you have a tube

and you get more flow through it, the velocity has

to be faster through that tube, okay?

Contralateral,

more flow in the same size vessel

produces increased velocity.

What do we do?

What are the ultrasound rules?

I will tell you that I've been following the

ultrasound literature on this forever waiting for an answer.

And there is no answer so far.

There are people

who said you subtract 20 centimeters per

second from the number.

Some people say you subtract 30 centimeters.

Some people say you abandon it completely.

You just say there's something there.

Other people say use a ratio.

I think, I don't want to say who may do what.

I just look at the gray scale, look at the color,

and I generally move it down by one full grade.

This had a,

a ratio

of slightly more than two to one

and my grade, which would put it as above 50%,

but now I'm gonna downgrade it.

The gray scale in the color did not look bad,

so I'm gonna call it less than 50%.

Okay? Anybody have a problem with that?

Anybody not have a problem with that? Okay, excellent.

Somebody didn't have a problem with that. Okay?

Here's another one on 196 that had an angiogram.

The Case of the Confused Carotid

The case of the confused carotid,

by the way, I am told my PDF did not arrive

and so they say it's gonna be put on.

Look forward tomorrow.

Here's

is a waveform on the lower left of the common credit artery.

And here is something my sonographer Ken is telling me

that he thinks is the ICA.

I will tell you that there was an ECA

that had a very typical waveform,

in it.

And so this is what he got.

And these are the color pictures of that area

that he was getting this waveform from.

Okay, do I have a brave soul in the audience?

Who wants to tell me what they think?

Do I have a stupid soul in the audience

who's willing to tell me what they think?

Man? What? Dissection. Dissection.

Okay, that's a,

this is, it looks to me.

Thank you. Was that Mindy? I believe so.

There's a lot of stuff in here, dissections as a rule

or a hemorrhage in the wall.

This kind of looks a little more irregular.

And this patient is 78 years old.

Dissections are a good thought.

It's one of the things

that can give you a highly pulsatile doppler waveform.

I did wanna point out the velocity here.

That was,

some high number

250 or even more.

Oh, higher. Other higher.

Okay, does anybody want to commit to A,

A, B, C, D, E, F?

All right, let's do it this way. Any a's, any B'S.

CDEF.

Ah, I got an E,

FGG

technically inadequate.

It was, it was the best we can do.

I got one vote for one E.

I don't know who you are, but you're genius.

You're absolutely right.

This is a very strange waveform

and it has very high velocity.

What, what is going on here?

This is this kind of this famous Spencer Reed diagram.

And what happens in is as you go up, your velocity goes up

and there's a point at which your velocity goes down.

But in this area right here, it's a very strange place.

There are all sorts of weird things going on.

And what's happening is there's so little lumen here

that you can, sometimes you get high velocity,

sometimes you get normal velocity

and sometimes you get low velocity.

You get these weird things that are happening.

What's happening is during systole,

you're pressurizing enough to get the pressure gradient.

But basically when you start dropping your pressure,

it basically is so small it closes

and basically you get what looks like reversal.

Basically this stuff gets sucked down.

You get this weird flow, which is present release.

That's how I interpret it.

This, the patient did have an angiogram.

And the other thing that was important

to recognize was this was a very long lesion.

And the numbers that we're talking about, again,

the grant numbers or any

of the numbers are based on a couple

of things which are short stenosis.

Once you get to long stenosis, your,

the normal rules do not apply.

This is either to and fro

because of the resistance related to this very long stenosis

or related to the degree of stenosis or both.

Okay? And by the way, on color doppler

and power doppler, it looks like a very

severe looking stenosis.

John, did you vote? Yes. Which did you vote for?

E Of course you did. It was, it was obvious though.

I would ex I would expect no,

I would expect no other answer.

The Case of the Slow Carotid

This is the case of the slow sonographer.

No, the slow, I'm sorry, did I say that out loud?

I apologize. You did the slow carotid.

Okay, there's a power doppler image

and a, a spectral doppler image with a velocity.

And the velocity here is about 20 centimeters per second.

That's what makes it a slow sonographer. Okay?

Same thing. Let's see if these people,

let's see if I can get two people's vote for this one.

What do you think, John? Do you think I can mobilize double

my possibilities here?

Easy. Easy. Okay. A anybody?

A, B, one, B, C,

D, E.

I got 1, 2, 3, 4. I got a lot of E's.

Oh, and, and little Johnny.

F little

and G.

Anybody G? Okay.

This was near occlusion

and this is just like,

we were talking about

before,

we were up here for that first weird case.

This is now a little bit further down the road

where you have, again, a very long stenosis where the,

the lumen is so tight you can't even get

a fast velocity through it.

It just is kind of squeezing through it as,

you get through this range.

Again, it's either related to small size

and the small size can be due to a couple of things, right?

One thing it can be is you don't have enough pressure in

that artery to actually make the vessel expand,

or it could, so it's just shrunk down

because it's a very low, small thing.

If you saw the, the,

musculoskeletal section,

it was very much what happens to nerves, right?

The nerves swell up and then distally, they get all shr.

The vessel is small

and our,

angiography call that adoptive narrowing.

It could be that it's, it's actually a shorter stenosis,

but it's got no pressure.

Or it can be that it's a long stenosis.

Those are your two options. It doesn't matter.

They're near occlusions

and they are associated with,

kind of the end

of the line for these patients.

The Case of Calcification (Crunchy)

Crunchy. This is an important case

because it's something that we face every day.

I was at a session, Excuse me,

of a vascular meeting and the,

and the, a guy presented a paper from a very famous

institution in Boston, not the Brigham

and Women's Hospital,

where he said

that carotids were not very accurate in the presence

of calcifications.

He said worthless. Okay?

Calcifications do represent a problem

because you can't see underneath the calcifications, okay?

I totally agree with that, but let's see what we got.

We have the proximal internal cord artery with a shadow.

Everybody see the shadow? I know it's late in the day.

Everybody's good here. Okay, good.

Common credit artery a hundred nine seventy nine right

before the calcification in the shadow.

Nothing beyond the shadow 79,

but with a bunch, whole bunch of turbulence, right?

Okay, what do you wanna do?

Measure the length of the shadow.

Measure the length of the shadow.

You've obviously heard this lecture from Dr.

P*****k where he, where he claims that the length

of the shadow is related to the accuracy of the ultrasound.

I will tell you that,

I heard that lecture

and I've been looking at that myself.

Much as I love Dr.

P*****k, I have not been able to confirm his results.

Good thought, but not today.

But it's not a bad idea to,

what's the problem You want to get?

See what the hell's going on underneath it, right?

Anybody not think this is a technically an adequate study?

How many people would read this? Less than 50?

'cause it was 78 on both sides.

Nobody, 'cause this is a very smart group

and they all said there's a lot of turbulence here.

We're really nervous. Some

of us might say technically in adequate study

'cause there's turbulence and I dunno

what to do with it, right? And it was one

Other thing, There's one other thing. It was

Reversal in the common.

There was reversal in the common.

There was the, there was a little bit reversal right here.

Good point. You're thinking

there's a lot more action going on?

Yeah. Yeah. Okay.

What do you do?

That's an interesting question, right?

I have 28 minutes and I don't know how many cases I have,

but let's talk about this for a few minutes, right?

I mentioned this to sonographer.

This is a big calcification there.

They go, yeah, I said, you didn't mention

that there was a big calcification on the, on the worksheet.

They go, I know. I said,

kind of helpful to do that.

One of the things that you have to realize when working

with sonographers is that when they don't know something,

there's two options, right?

One is to hide it and the other is to reveal it, right?

It's, and this is the difference between

what we call guilt and shame, right?

Guilt makes you kind of confess and shame makes you hide.

The point is that you need an environment where

question marks, anything uncertain gets opened up.

This is their opportunity

to talk to you 'cause they have a problem.

I said, next time, put it on the preliminary

and let's see what we can do.

What I suggested is we try scanning a little bit more.

Okay? I said, you know, most calcifications,

the most plaque is not symmetrical.

If you find a different angle,

you might be able to find the lumen.

And sure enough, they, we went to a different place

and we found the lumen going through

and now we can put our doppler through it.

There's one other thing that I don't show here in end fact.

I routinely also tell my technologist

to angle the steering box downward instead of upward

because they're always thinking about putting the box

up towards where they're going.

But you want to get underneath this plaque.

The other way to get under the plaque is by

angling downward because the shadow is gonna cast itself

down towards the feet

and you get a little bit more inside of the plaque.

That's another trick that I tell them to do.

We did this

and they actually found a peak systolic velocity of 159.

There is not a lot of diastolic flow here.

There's a patient who had other cardiac issues, John.

That was a good pickup,

but I'll show this another year for,

heart problems.

The ratio turned out to be two

and we were, we confidently made this a diagnosis of 50

to 69%.

The Case of the Misidentified Vertebral Artery

Anybody know what movie this is from?

This is from high Anxiety by Mel Brooks. Okay. Yeah.

Okay, this is the right vertebral artery, okay?

I have showed this case to John and a panel of five experts

and nobody picked it up.

You're not giving the di the

the scale.

You can't tell the direction of flow,

The direction of, actually, it's funny you should say that

because here's the, here it is,

it's flowing in the proper direction, John.

It's not inverted.

There's your waveform

and it's an, if the number is 35,

it's flowing in the proper direction.

Okay? What do people think?

Ver Pardon?

Sure Am I sure it's the vertebral?

I know the answer. Are you sure it's the vertebral?

Okay. The vertebral is typically found someplace

between the lateral masses,

and I don't see lateral masses on this picture.

This may not be the vertebral.

Remember, the vertebral doesn't necessarily have to have

the external carotid branches are, are lying up there.

It looks like an external

and okay, we tell them no good, keep on looking.

I would've been happy with

that being a vertebral

except that it was in the wrong place.

You gotta look at the pictures

and you gotta see where it comes from.

In fact, when we scanned in the proper place,

we did get a two and fro sign,

the vertebral was there.

Again, what

Vessel was that? That

is just probably, I don't know, it's,

the, the

thro cervical trunk.

John,

how's that?

Yeah, sure. Okay. Thank you very much.