Transcript

Hi everybody, this is, uh, Dr. Jason Cox,

coming to you from St.

Louis, Missouri. I'm here in our ultrasound clinic,

and tonight we're gonna talk about, um,

ultrasound of peripheral nerves.

Uh, the first thing we're gonna go through is, um,

How we're going to, um, image peripheral nerves,

why you should be doing it,

and then also by the end of the course, you're gonna be able

to confidently look at a nerve yourself at your own clinic.

Um, but before we get started, we're gonna go ahead

and talk about our disclosures.

Um, basically, um, nobody at the Institute

for Advanced Medical Education, uh, myself

or anybody else involved in the planning

of this educational event, has any, uh,

pertinent disclosures

or financial interests, uh,

that we need to talk about today.

Um, if you need

to know further information about our disclosures,

you're welcome to check out that statement, um,

after the conference is done.

So, Joanna, we're gonna move on to the next slide here.

Um, go ahead

and throw up our, um, introductory

slide there again, Joanna.

All right. So what we're gonna talk about first is a little

bit of anatomy and, um,

when we're talking about anatomy, um, you know,

today we're gonna use the median nerve as an example.

We're gonna use the median nerve

because it's one of the most common, uh,

peripheral neuropathies,

or it is the most common peripheral neuropathy, uh,

that you would probably be familiar with

as carpal tunnel syndrome.

Uh, about 3 million Americans a year get carpal tunnel

syndrome, and there are far fewer,

uh, surgeries done for that.

But then there's a lot of different treatments that are done

as well, like, uh, nerve injections

and, um, other treatments like physical therapy.

Um, and when we talk about, um,

nerve anatomy, the nerve is gonna be familiar to a lot

of sonographers and physicians

because it's running in parallel with some arteries

and veins that you may already know about.

Um, as we can see from this, this old, um, you know,

gray's anatomy, um, image here, you know, all

of the nerves come back up from the arm

and coalesce into the, um, the brachial plexus, which is

above this place, uh,

of the clavicle and goes into the neck.

Um, you can see that the, um, median nerve

runs down the arm along the biceps muscle,

passes the elbow in the front of the arm,

and then extends down through the forearm in

between some muscles, and then

through an area called the carpal tunnel

into the hand dividing into the digital nerves

and supplying, uh, innervation for sensory

and motor, um, into the thumb index finger

and part of the middle finger.

So, um,

whenever these patients come in, they're gonna present

with numbness and tingling in, um, these fingers right here.

It's like the, the, you know, little pistol sign there,

and it'll have characteristic sparing of these two fingers.

Now, just because you have those symptoms in these fingers,

and not these fingers, doesn't mean

that it's not coming from the neck

or somewhere higher in the arm.

And we're here to exclude the possibilities of it being in,

in the, in the distal part of the, the nerve

and not up in the neck,

where you can also get similar symptoms, which would,

you know, the most common cause would be disc

disease in the neck.

Um, so, so just today,

we're not gonna dive too deep into the anatomy

of the median nerve because this median nerve isn't

necessarily representative of all nerves,

but it is representative in the fact

that all nerves look similar to this,

and it's one of the easiest ones for everybody to do.

This is an introductory course to, uh, doing peripheral,

um, nerve imaging.

Um, I'm just gonna show you some information about

the protocol that we're gonna use for the median nerve,

and we're gonna start down actually at the, at the, um,

at the wrist so that we can actually get a good idea of

what, um, nerves look like

and what they're supposed to look like

and what they don't look like.

So, I'll, I'll do the real time demonstration,

but this is the picture that I wanted to show you here.

So, as you can see, the median nerve, this is at the wrist,

and this is what a normal nerve looks like here with

what we have is vesicular architecture.

We have these nerve fascicles that are surrounded by

intradural fat, and it gives you a honeycomb appearance.

Um, this should be well circumscribed.

It should be, you know, pretty well delineated

and you should be able to see it very well.

This one is, is at the pre tunnel,

or right prior to, um, going into

where you would see the lunate bone right next to it.

Just jumping the gun here is a severely abnormal nerve.

And you can see that the nerve is a little bit

enlarged compared to this one.

These are not the same patient. This is a female,

and this is a male, and males tend

to have bigger nerves anyway,

or you know, how tall the person is.

Um, but this one,

you can see it doesn't have a honeycomb appearance.

It has kind of, uh, indistinct margins.

It's lost all the bright spots in it, the fi,

the vesicular architecture.

And this is characteristic of carpal tunnel centro.

So what, there's, there's a couple

of different things when you look at these nerves, um, that,

that you can see that are characteristic, um, findings.

And we'll talk about those a little bit too.

Um, we're just gonna run through Quickly

and talk about, um, the median nerve primarily

at the wrist joint, but then we're gonna go

through the whole arm as I scan live.

And, and as I go through these areas, I'll talk about, uh,

some things that you need to be looking at

and some, some normal, uh, anatomy.

And remember, we're not focusing too much on the

median nerve specifically.

We're just using it as a great example

because it's one of the most available

nerves that you can look at.

Um, I think most people from this webinar are gonna be able

to take the skill that you're taught, taught tonight, and go

and either look at yourself

or even look at patients, especially if you're doing, um,

DVT studies or if you're a vascular sonographer and,

and you're looking at arteries, these nerves,

you've been looking at 'em for years

and you just may have been overlooking that they're there.

So you're gonna start to see new stuff

now that you learned this anatomy.

Alright, Joanna, let's go ahead

and look at the ultrasound machine here

and then go ahead and blow up that ultrasound machine.

And we don't need the, uh, slide lectures anymore.

The rest of this is just gonna be show and tell.

Okay. All right.

So the first thing is, is you're gonna need a linear probe.

This here is a, uh, linear 15.

Um, many machines are great for this.

Um, all modern machines have pretty high resolution

or pretty good for this, Joanna, don't show that, um,

lecture slide anymore.

Okay.

I,

All right. So right now,

Joanna, we just need that.

Um, let's blow up my picture here

so that we can see this probe.

So a linear probe is what you're gonna use for, for nerves

because these have the highest resolution

and they're good for, uh, superficial, um, structures.

As you know, obviously, if you get into some bigger nerves

or deeper nerves like the, the sciatic nerve,

which is the biggest nerve in the body

and it's very deep into the thigh, that'll be, um, something

that you're gonna have to use this 15 four

or even something like a nine

that can see deeper depending on the patient's body habits.

Um, other probe choices would be something even more like

the hockey stick or this, uh, 19 megahertz probe Here.

We're gonna look at the difference between both

of these probes on today's exam, on both normal

and abnormal nerves.

Okay? Um,

you should use the highest resolution linear probe

that you have available so that you can get your pictures

and anatomy at the highest resolution possible,

because the higher the resolution you get

and the more detail you get, the more, uh,

pathology's gonna show up in these nerves.

Whereas if you just have like a nine megahertz,

then you know, maybe it's gonna look

abnormal or maybe it won't.

And, um, you know,

we're gonna talk about a couple of those things.

But what we'll do first is we're gonna start with the,

the 15 and Joanna, go ahead

and pull up the, um,

make the ultrasound picture the biggest picture for me.

And as soon as we get that picture up, we're going to, um,

start showing some, some images of the median nerve.

We're just waiting for that image

to come up here while we're waiting.

Um, there's a couple of things that you need to know.

Um, when you're using your, your pressure here,

or when you're holding your probe,

you wanna hold it more like a pencil.

And when you're holding this probe like this,

you're gonna use the base of your hand

to stabilize your probe

and to slide along where you're going.

You also can use you, you do use a lot of gel.

Um, I probably use more gel than anybody.

And, um,

whenever I do this, um, I'm constantly adding gel

or using gel as a standoff.

You can also use standoff pads depending on,

um, you know, the application.

Now what we're gonna do is I'm gonna unfreeze the machine

here and

I'm gonna get on the right probe,

and now we're straight into the, the median nerve.

Okay? So I'm gonna be talking back

and forth to you guys here with the median nerve picture

and the, um, and the lecture.

So, you know, you may or may not see my face.

We're gonna go ahead and freeze on this nerve right here.

And again, we're gonna use the lower one so

that we can get a realistic picture.

'cause some people might not have that probe,

That's all.

Okay, I hope everybody can see that now.

And, um, we're gonna focus on this anatomy

instead of my face.

So I have this frozen here,

and I'm gonna unfreeze so that we can use some, um,

the pointer here and actually

point out some anatomy here.

So we're gonna start away from right when we start

to really see that nerve and then we'll,

we'll go ahead and freeze it.

Now, whenever we are doing this,

I'm gonna just show you with the calipers

here where the nerve is.

And what I'll do is I'll trace it

because that's actually what you need to do

to start your journey of diagnosis

of carpal tunnel syndrome.

So here we're proximal to the carpal tunnel,

and I'll, I'll show you how to figure that out here shortly.

But I really wanna focus on these, um, on these, uh,

characteristics of it.

So now I'm gonna use my trace tool here.

What I'm doing is I'm tracing right along the edge

where the fat meets the dark nerve,

and then we're gonna Freeze that there.

And then everybody saw where that was and,

and you noticed that it was, uh,

0.10 centimeters, cross-sectional area.

That's, uh, centimeter squared cross-sectional area.

Well, when you're looking at this in the median,

the median nerve in the carpal tunnel, the upper limits

of normal is 0.09 centimeter squared cross-sectional area.

So already, you know that I have a larger than usual

median nerve just prior to my, uh, my carpal tunnel.

So if I get into my carpal tunnel,

I'm gonna maybe have to use a ratio.

Um, you know, if, if your nerve is 0.0

or is 0.14 centimeter squared in the carpal tunnel,

and the proximal is is one, then it's a, it's a,

it's a 1.4 times ratio there,

and that's actually diagnosed agnostic

of carpal tunnel syndrome.

So, but really what we're gonna focus on here are some

things that are gonna help you become sonographers

that can do these.

The first thing is bony landmarks.

You're gonna have to learn those for the nerves.

But, um, so this, this big echogenic focus right here,

uh, I'll phrase that and roll back on that

and then I'll put even an arrow on it here.

This thing right here is the lunate bone.

That's the, the first bone in the middle of your wrist

that articulates with your radius.

So that's your first landmark there.

Uh, when you measure your median nerve,

there's different ways to do it,

but we like to measure it at the, at the lunate or beyond

and deeper into the, into the carpal tunnel so

that you have a standardized approach.

So every one of your protocols, when we, you know,

right now we're just doing general peripheral nerve,

but you're gonna have a protocol for median nerve.

You're gonna have a protocol for ulnar nerve,

and you'll have one for radial nerve too.

Um, and then, so we're gonna put the lunate right here.

Go ahead and label that guy.

And then here's your median nerve up here.

And this is actually how we, we want to do it, you know,

when you're gonna present these to your doctor,

you wanna have a standardized approach to telling the doctor

or, or your radiologist

or whoever you're doing these for, Hey, this is the lunate

and this is where I'm gonna measure it,

and here's the median nerve.

And whenever I go to measure it,

I'm gonna do it the same way every time on all my patients.

So then we have a standardized, um,

number one in internal lab

or internal, you know,

imaging department standard for nerves.

And then also, um, you know, you can say, Hey, a CR look,

I'm doing these the same way.

And just so you guys know, there's a new code just

for peripheral nerves, and we'll talk about

that protocol before we're done today.

So now we're done doing that kind

of baseline introduction to a nerve.

And then, so that's the cross-sectional area.

And what we wanna do now is look at the, um,

we're gonna look at what a nerve is supposed

to look like in the, in the long axis, okay?

And so obviously probe's gonna be up towards the patient's

head, just like anything.

And then we're gonna bring that nerve into plane here.

And then we're gonna point out some features of this nerve

that are interesting and valuable to know.

And again, I'm doing this on myself.

I do have a, um, a volunteer here,

so we can look at some of this also.

But what you can see here is I'm gonna roll

through this nerve and I'm gonna show you a sign

that is actually a healthy nerve sign.

Um, So you're gonna see right here

that this nerve, here's the fat

that's surrounding the nerve, superficially the palm is up

here, here's the lunate right here, here is the

palmar aspect of the, the radius.

And then here's a bone called the capitate.

It looks like a saddle. And

whenever you show me this, I don't, you know,

of course you gotta label stuff,

but if, if you were to send me this picture,

I would immediately know exactly where we were

because these bony landmarks, Marx Van Holby, very famous,

um, um, MUO fellow radiologists, he's always talking about

and teaching about bony acoustic landmarks.

And this is an excellent example of that.

So what we're gonna talk about here is the tram

track appearance of the nerve.

So the tra the nerve is gonna have small

white lines running through it.

And you can see that this, you know, you can imagine

that's like a train track or tram track right here,

and that's evidence of a healthy nerve.

If that's gone, that's evidence of a diseased nerve.

So, um, so now I'm gonna use my volunteer here

and we're gonna look at, um, maybe, you know,

my nerve's not actually the healthiest.

So we're gonna actually look at, um,

This nerve on a young healthy patient.

Um, and you may not be able to see it,

but a lot of times what I do is I'll, I'll put the arm,

like I'll put a towel roll like this,

and then we'll go ahead and get into this nerve.

And that helps expose the nerve for, for imaging. Okay?

So first we'll start in that long axis

so we can identify our anatomy.

Again, you can never use too much gel.

So the first thing we're gonna look at is the bony acoustic

anatomy, and here is our lunate.

Okay, on this patient. Here's the lunate,

we'll pull up a arrow here.

Lunate radius, capitate, here's that saddle

that I was telling you about.

I'll show you something else here. Here's a growth plate.

This patient is a teenager,

so they will have some things going on that aren't,

you know, typical for adults.

So then in order to find the nerve,

you go in the short axis.

This, the lunate is actually gonna be

the tallest bone in this carpal tunnel.

So that's, see how that's the tallest?

And then you get down into here

and you have the, the hook

of the handmaid and the pisa form.

The, uh, pisa form is right here

and right next to it, it happens to be the ulnar nerve.

And then over here is the hook of the handmaid right here.

And here's the, uh, triquetrum over here.

And then here is the radius.

So again, we kind

of have our carpal tunnel figured out here.

Now, in this short axis here,

since this isn't a lecture about the carpal tunnel,

we're just really focused on this nerve.

And this is probably kind of

what you guys are gonna get in practice with your fifteens

and, um, things.

One pro tip is that if you're,

if this is on MSK setting right here, if you want,

and you're having trouble seeing the nerve,

put it on superficial or, um,

or even, uh, thyroid, thyroid, thyroid

and breast I find are some

of the best presets for these guys.

And so this is on a, uh, superficial setting,

and we'll go to the lunate.

We're gonna freeze that kind of roll back

so we can get our particular architecture

there, right there.

Now I'm gonna measure that guy using the trace function.

So every nerve that you do, you're going

to trace it in the short axis view.

And this isn't easy on a track ball or a, a slide pad,

but you can see this is normal 0.08 centimeter squared

cross-sectional area for a six foot male,

that's a pretty good, good nerve.

Anything under that, you know,

0.09 is gonna be a normal nerve in most circumstances.

So now that we, so I also wanna show you some things here.

So I'm gonna put a gel pad on here so I can show you

what the pressure can do to a nerve.

Okay, so see now I've got the gel pad.

This nerve is kind of like an oval or a, um, almond shape.

Now if I push on it, now, look at it, it's very flat.

Flattening of a nerve is a sign of pathology or entrapment.

So you need to be careful

that you're not causing a pseudo entrapment or,

or, you know, faking out what you can see here.

Um, so now we're gonna come way down into the carpal tunnel

and just show you a little bit of stuff here.

Typically, whenever you see carpal tunnel, uh, syndrome,

just get a little bit more gel.

Typically when you see the carpal tunnel syndrome,

it's gonna be down here in, in the tunnel

beyond the lunate here.

Just Do a little bit of optimization here.

Now what I'm gonna show you here,

this is the transverse carpal ligament right here.

This thing right here. And that is what gets thick

and causes compression of the median nerve.

And that is where the pathology is gonna be.

This is going to, sometimes you'll see that it's dented down

and flattening the nerve there.

And then this nerve will be thick right here proximal

to the area of flattening.

Um, and You can see here,

there's a very nice tram track

as you go back and forth through it.

You know, sometimes it's harder

to see just on a static image,

but definitely when you go through here, you can see it

now on the protocol for, so, so, you know, we've kind

of dove, dove into here and,

and we've seen, you know, normal looking median nerves.

Um, you know, mine's a little bit big.

I have a little bit of carpal tunnel syndrome

sometimes, I'm sure everybody does.

But, um, now what we're gonna do is, is

what they want for the protocol.

So the protocol says you need

to show a peripheral nerve in its entire length, um,

and then store those asinine clips.

So basically what you're gonna do is either you're gonna use

prospective or retrospective, whatever you like to do.

Um, you're gonna start, you know, I,

I like to start at the carpal tunnel.

That's where the money is. So you're gonna start there.

Then you're gonna just start going And you're just gonna

follow that nerve in the coaxial plane.

Take some, you know, sending clips here.

Now I'm just following it along

and it's gonna start to be harder, you know,

the untrained eye, it's gonna be difficult to see,

but I'm keeping it in dead center.

And then it'll start to reappear.

So here we've got some, some nice fat around the nerve.

I'll freeze that and show you the nerve right here.

So here is the nerve. You can see that it's, you know,

a little bit difficult to see.

You could, um, you know, if your machine allows you

to adjust your, um, your, um,

focal zone, you know you can do that.

So mine has an auto focal zone here.

And then, you know, basically what I like

to do is just cook this whole arm in and gel

and start my way working it up.

So now we'll, we'll start down here again

and if you get lost, you just come right back down

to the good old carpal tunnel

'cause you're gonna be able to find it from there.

So now we're following that nerve up,

keeping it in the center.

You're like, where'd that nerve go? I can see it just fine.

Um, we'll do a little bit

of optimization here, maybe it'll help.

And as we come up, there you go.

There's a very nice media nerve

And now we're at the elbow joint.

You can see that down here on those bony acoustic landmarks.

And then we're gonna follow that median nerve

up into the arm.

And if anybody, if you have ever, you know,

evaluated PICC lines, you're gonna be very familiar with

with this because it's gonna be right next to the, the,

the brachial, uh, vein.

So see, I'm still following it there.

Now I'm a little bit more superficial,

so now I'm gonna get deeper so I can see

or get more superficial on this

so I can keep following it and go up.

Now, peripheral nerves as they get di more distal

and distal, they have more

and more, um, kind of fales, smaller fascial,

but as they get more proximal in the arm here,

you're gonna see that they grow like a couple

dominant fascial, you know, so this guy here has like,

you know, two dominant fascial.

And then we'll put a little bit color on here.

So you can see what we're working with here.

We'll kind of compress these guys,

see what's the vein and what's artery here.

Go back to gray seal

and then we're gonna keep following this up.

Once you get up into the armpit, you're gonna start to see

the median nerve, ulnar nerve and radial nerve all coalesce.

And the musculocutaneous nerve,

which is making an appearance right here,

which is actually the, the, the nerve that that, you know,

controls the biceps.

So again, you're gonna get your nerve pictures,

you're gonna run all the way through, get nic clips.

I, you know, my machine doesn't like anything more than

a six second cynic clip.

So, you know, You run through this whole nerve, this is

what you gotta get in your dictations.

You're gonna say the, uh, entire length

of the nerve was imaged and eclipse are stored to the packs.

That's how you guys get paid for this stuff.

Okay? So now we've kind of went along the whole track

of the median nerve with this 15 megahertz probe

showing how you're gonna do it in real life.

Now we're gonna get into some more high definition anatomy

so that we can really, um, feel, feel

that we're comfortable with looking at nerves.

Okay? Now I've got a couple presets here that I like,

and I'm sure you'll get some good presets for yourself,

but you're gonna see the, the massive difference in here on

what you can see on a nerve.

Okay, so now

it's gonna be a lot easier i for you to measure this nerve

and, you know, evaluate the architecture

and then now you can even see the nerve.

So you can see the, um, the retina aum here.

So this little hypo coic line right here coming across on

top of the fat, that's the echogenic stuff,

that's the flexor retin aum of the forearm.

Here is the median nerve.

And then we'll go ahead and we will,

um, do some measurements.

So again, we wanna identify that ate.

So there, I'm deep down in the carpal tunnel.

I'm gonna come back to the

radiocarpal joint.

If you get lost, just go a little bit deeper

and then you'll see this stuff.

Here's the lunate right here. So I'm very happy with that.

So then I'm gonna turn on that and the short axis,

and then there is my nerve

and there is the spot that I need to measure it.

And I like for my sonographers

and myself to have that lunate in the picture when I measure

it so

that I know what's going on there.

I, Now here's a, a vein right next to it.

If I push, it's gonna get flat.

If I come up a little bit, it's gonna get more rounded.

Go ahead and move your fingers here for me.

So this is what it looks like when

the patient's moving their fingers.

You can see the flexor tendons popping

in and out of the field of view.

And then you have a muscle belly right there.

Go ahead and move it. And you can see the

difference between, okay, stop.

So now this is a key point of view here.

All right, I'm gonna measure

the actual median nerve.

Okay? So this is the median nerve right here.

I'm gonna measure it so you guys can see the borders.

If you trip up a little bit, just go back and retrace it.

The other thing too is I've done a lot of, um, kind

of just experimentation

and if, if you don't have a beautiful line there,

it's not gonna change that much in the, um,

in the cross-sectional area here.

So here, um, we've got this at

0.09 centimeter squared cross-sectional area, which

would be abnormal in a person that wasn't tall.

And if this was a hypo nerve,

but you just, you don't go off just the area right next

to it, which I wanted to point out here

is the fibrillar architecture

Of the tendon.

Fibrillar fascicular.

So the tendon, a lot of times I will see people

that are inexperienced

or sometimes even experienced people

that see a pathologic tendon measure it as the nerve.

And then, you know, as long as we have that, that lunate in,

in the view, which we took it outta here just for

to show you that that thing, you know, you can say, Hey,

that's not, that's not the tendon, right?

So freeze that. You can see that there's a tendon here,

a tendon here, a tendon right here,

some tendons down here.

And this guy with the honeycomb appearance is the

beautiful normal median nerve.

And then here is the lunate.

You can see that it's a little bit off

to the side from the luminate,

and that's a completely normal nerve.

So then, so here's our, our

bone nerve coming down into the carpal tunnel.

As nerves dive into angles, you're gonna have

to angle your probe and you'll notice that you know,

there's skin or there's, there's other stuff in the way

that's causing problems to see these,

these median nerves or these nerves.

And you have to just heal or toe

or um, angle your probe

until it gives you the best picture as usual.

Now, just to show you the power of ultrasound

and how nicely you can see nerves,

I'm gonna follow this median nerve down into the palm

until it turns into digital nerves.

Okay, so now we're watching this right here,

and you're gonna see this guy split into multiple nerves.

So here that it splits into the first

or the third digital nerve right here,

the second digital nerve and the first digital nerve.

So now we're gonna follow this digital nerve all the way up.

Now I'm gonna, it's very superficial, so I'm gonna get close

to it, some optimization here,

but I'm gonna follow this nerve all the

way up to the third digit.

And then we're gonna be able to see this turning in.

So right next to it is the

flexor digitorum superficialis

and flexor digitorum profundus tendon.

Right here of the third digit,

I have this third digit in my hand

and I'm moving it right next

to it is the third digital nerve branch

of the radial side right here.

See, I'm jiggling it around right there.

This is how powerful ultrasound is for looking at nerves.

An MRI can't get close to this.

Now if we go into this view right here,

we're gonna see both digital nerves.

Here's the radial side, third digital nerve,

here's the NAR side.

Third digital nerve. Both

of these are gonna have a paired artery and vein.

Most of the time in our clinic when we're seeing these

and we're actually evaluating these nerves, it's

because there's been a laceration or fracture

or previous surgery and the person has persistent numbness.

But here you can see the digital artery and vein aim

and how fragile or you know, easily it is compressible here.

And obviously if the patient can tolerate it,

you can have 'em rotate their, their handover

and then get a real nice picture of that.

And in case you guys don't believe me,

I'll just show you here is the,

here's the third, uh, metacarpophalangeal joint right here.

This is the head of it.

And remember, this is a young bone that's not fully formed.

Here's the articular cartilage, and here we come out here

and then again, add more gel.

The, the resolution is absolutely amazing on these

you ever heard of, um, uh,

climber's finger or pulley rupture?

This is the thin one millimeter thick pulley that holds

that tendon down right there, just in reference to

how thick that is.

And that's about the same size as that,

um, that digital nerve.

Okay, so now we've talked about kind of normal nerve stuff.

So just in review

before we move on to some abnormal stuff, we want a diameter

that's pretty uniform nerves taper distally.

So you should not really have a nerve getting

bigger as you go distal.

If it's getting bigger as you go distal

and there's a ratio of, you know, 1.4 to one

or you know, a 1.4 ratio, then

that's an abnormal nerve

size and you need to think about it.

Well, you also have honeycomb architecture,

you have vesicular architecture,

and then you have tram track sign

all showing very nicely on this nerve.

That's completely normal.

And here we are down in the carpal tunnel again showing

tram, track sign and normal

architecture and normal anatomy.

This is just normal muscle right here.

And there's some other stuff in here that, you know,

once you get more advanced, you're gonna be wanting

to look out for like the, uh, recurrent branch

of the median nerve or the thenar motor branch.

I mean,

okay, so just, just, um, now we're talking about like some,

some other smaller nerves.

You know, when you're, whenever you're looking at very small

nerves, like here's the cutaneous branch Right here,

hallmark cutaneous branch of the nerve right here.

I'm just gonna blow that up

so you guys can see it and show it to you.

Um, so the palm mar cutaneous branch

of the nerve is important for the surgeon to know about.

So they don't wanna cut that guy right here.

And basically all you get is this little guy right here.

It's like almost a single fast goal

and that's the palmar cutaneous branch.

And you see it actually arises from the median nerve,

which is right next to it over here.

So there's lots of nerves, you just haven't seen 'em

because you haven't looked for 'em yet.

And then once you start doing this exam,

you're really gonna find out that there's

so much more that you can see.

Um, another one down here

that you're gonna eventually start looking at

is the, the ulnar nerve.

This is at what's called ion's canal.

It's immediately adjacent to the, um,

the Pisa formm over here,

that there is the ulnar artery.

I smash it down a little bit

so we can get a better look at the nerve.

And as I come out proximal ion's canal

get a nice view of the nerve right there.

And so if the patient comes in with a claw hand

or you know, hey, a history of, uh,

nar nerve injury from surgery or something like that,

and they want you to do this, you're gonna come down

to Geons Canal, you're gonna measure it there.

Um, a lot of the peripheral nerves they have, you know,

well all of them, they have characteristic, um, areas

of injury and characteristic areas of, um, entrapment.

And this is one of the spots.

So you know, you're gonna get that nerve measurement.

Remember this is the NAR nerve, we're just learning it.

And then now see how beautiful

and um, with vesicular architecture there is right there,

you have right next to the ulnar artery

with some branches coming off.

I can just follow this all the way up the arm

with this nice, you know, 19 megahertz probe.

And yes, it's gonna dive deep

and it's gonna become harder to see,

but then as you get up to the elbow,

you make your adjustments,

you're gonna see it in the cubital tunnel.

Um, this patient actually has had a, um,

ulnar nerve transposition,

so it's not gonna go into the cubital tunnel

that you can see right here That it

actually is a very nice nerve,

never goes in the cubital tunnel like it's supposed to.

If it's back in the cubital tunnel,

then there's been a complication of the surgery.

And those are the kind of things that you'll be seeing.

So remember, this is a normal ulnar nerve that has been

transposed, taken out

of its normal position into another position

because of cubital tunnel syndrome.

That's a nice nerve. It's got all kinds of, uh,

architecture and it's very nice.

This used to not look like this.

I remember when it was, it was a bad nerve.

So, so now let's talk about what bad nerves look like.

Um, I have cubital tunnel syndrome.

I'm gonna show you my, uh, ulnar nerve in my cubital tunnel

and then we're gonna get some pictures here.

Um, the way I do my patients a lot of times

with peripheral nerves is actually have 'em lay down on the

bed and then just put their arm out.

Um, if you've got an arm board, that's extremely helpful.

If you don't, I have them, um,

just put their arm out, like, like right here.

I have the bed up with the leg out as a table.

I just have them lay it out right

there and have them sit on a chair.

I've had patients vagal just from doing nerve diagnostic

studies, so I do keep an eye out for 'em

and make sure they're not getting dizzy.

Um, sometimes these can be pretty painful to do just from,

um, how irritated their nerve is,

especially if they're a post-op case.

And on those cases I use a lot of gel

and use, use, uh, you know, as least pressure as possible.

Okay, so now we're gonna go, uh, Joanna, show me the, uh,

just put up, just put up the, uh, ultrasound picture.

Again, I don't need to see my face or anything here.

Okay, so now I'm in the forearm.

Okay, so now we're gonna pause that.

I'm gonna roll back on it

and now I'm gonna show you how to do a nerve,

an abnormal nerve evaluation.

So one of the known pinch points in the

arm is the cubital tunnel.

Um, we're gonna say that this is,

we'll just put this here for now.

We don't have to put that there.

Um, but I am gonna label this.

So I I would say, you know, left, um, ulnar nerve.

Um,

and then I, I typically put like I, I ate everything,

you know, uh, ct, okay, so that's cubital tunnel or,

but I, I'm gonna delete that

and say forearm, okay fa take that picture

and then I'm gonna measure it.

Save that picture unfreeze,

then now get ready for it.

This is gonna turn into one

of the grossest nerves you've ever seen in your life.

And what that is, is you see,

here's our honeycomb right here.

I'm gonna go up a little bit on the depth

so we can see it a little bit better.

And then it's gonna start to get fat and get bigger

and bigger and bigger

and lose all of its normal architecture

until it looks almost like a mass.

So I'm gonna freeze that and roll back on it for you guys.

And now this is the cubital tunnel. Okay?

I'm gonna use my arrow to show you

this bony architecture right here is the humeral condyle

with the cubital tunnel groove right here.

The cubital tunnel is formed by Osborne's ligament,

which is this hypo coic structure right here.

This is such high resolution probe.

You can actually see it here and the posterior wall

and um, lateral wall is formed by the bone

and then everything else is formed by the soft tissues.

So as you can see, you know, here's my nar nerve,

I'm gonna change my, um, my text here from forearm

to um, cubital tunnel.

Then I'm gonna measure this

guy with the trace feature.

And you remember it was 0.07 in my forearm,

so it got way smaller than this.

And see what we are today,

0.15.

So it's more than double the size of the distal nerve. Okay?

Now we've saved that image, we're gonna unfreeze

and then we're gonna go back up to the forearm

and get a good, so, so again, we're gonna come back up

to the forearm through the cubital tunnel right there.

Get up into my arm where it's a normal size

freeze that roll back on it,

the best cross-sectional area that we can.

There you do have some tram track

there with some normal fat.

And now we're gonna measure this again,

0.05.

So the nerve is three times larger than its proximal nerve.

And remember the nerves always taper from larger

to smaller as they go distal.

So that's markedly abnormal. It's very severe.

I've seen worse median nerves than this,

but I haven't really seen that many, um,

ulnar nerves as bad as mine.

But, um, so now you've done your cross-sectional imaging,

you've proven that there's carpal tunnel syndrome.

Um, let's just say you have a skeptic.

Now we wanna show you some other signs that you can see.

So right here

and you can't even get the whole abnormal part in there,

but you can see that the

normal particular architecture is gone.

There's no tram track.

There should be tram tracking right here.

There's absolutely no fat within this nerve.

It's very thick. Now I'll show you the transition from

abnormal to normal on the nerve.

So we're gonna go through the, so right now I'm in the

cubital tunnel, absolutely abnormal.

This is hard to do on yourself.

So then I'll roll this back.

You can see where it's tapering distally.

You can actually see where it's a little kinked right

here, right there.

And then you can see where there's t tram track actually

starting to form in the nerve

right down here.

So you see where it starts to get in there.

If I had the 15 on here, you'd be able

to see the whole thing 'cause you'd have

a wider field of view.

Um, basically what I have is called snapping triceps.

And so whenever I, you know, a lot of people, um,

and when they do this, they're gonna look

for a dislocating nerve here.

But what I have is when my muscle

actually comes over from my tricep and, and snaps it

and kind of pushes on it.

So, um, the triceps muscle, I'll freeze

that right here and show it to you.

But this is, this is beyond the scope of the course.

You know, you don't have to know this right now,

but it once you become advanced,

and that's, these are the

questions or an answer for the surgeon.

This right here is the triceps muscle.

It's coming over and it's pushing this nerve over to here.

The edge of this triceps muscle.

Every time I bend my elbow snaps against it

and there's a palpable snap,

You know, snapping triceps.

Another sign would be if it pops over the bone

and actually goes over the humeral condyle.

Mine is not of that character,

but there, there I can feel the snap right there.

And it's snapping against the edge of my tendon right there.

I just saw it. So like on those, if that happens,

I just hit the any button and then I save it

and then I, I tell the surgeon, Hey,

you can see it snap right there.

I felt it on with my hand on the probe.

And the, um, the diagnosis is snapping tricep syndrome.

He'll take out some of the muscle there

and re reposition the nerve.

All right, so we've got about 10 minutes left.

Um, we've covered all the signs of

what a good nerve looks like.

Peripheral nerve. We've actually gone in

and looked at a real cubital tunnel case

and saw how bad it can get.

Um, I would say most

of your cases will be more subtle than that.

Um, and you're gonna wanna look for, um, a dislocating nerve

where it comes over the side or other common things.

So each point of where a peripheral nerve is, you know,

like carpal tunnel, it's even gonna be caused by tightening

and overuse of that ligament and thickening of the nerve.

Or it could be a mass,

it could be an extra muscle that's inside there.

So it does help to compare both sides,

especially if you're new or even intermediate in skills.

Um, on my course I have a, I have a nice case of

that shows like an extra, uh, flexor digitorum muscle that's

inside the carpal tunnel causing carpal tunnel on a patient.

Um, we do have a full course on the ulnar nerve,

the median nerve and the radial nerve coming out next week.

The ulnar nerve and the median nerve

of course are already out.

Um, so we'll you'll be able to look at that.

But if there's any questions, that's

what I'd like to cover right now.

Hey, Joanna, do we have any questions participants?

Don't have? Okay, so no questions right now.

So, um, just to wrap things up, um,

I really appreciate everybody that joined us today.

Um, if you're interested in peripheral nerve ultrasound,

it's a very up and coming up and coming topic.

That's gonna be a very good skill set

for any sonographer and physician.

Um, you know, I see in my clinic about 20 to 30 cases

of median, uh, neuropathy, a week of carpal tunnel syndrome.

Um, either diagnosed in patients with arthritis

or diagnosed in patients that have coming in

with median nerve symptoms or they've had a surgery

and they can't understand, you know, hey, you know, the,

the EMG doesn't quite show what we see here.

We need you to look at the whole nerve and help us here.

Um, it's very good for post-surgery especially, uh,

better than MRI in post-surgical cases.

And, um, especially

with radial nerve injuries from prior trauma

where you have metal in the, in the humerus

or, or other things like that.

Uh, remember, you know, ultrasound doesn't care about metal

as long as it's not in front of what you're trying

to look at and it typically isn't.

So, um, I really wanted to thank everybody

for joining us tonight.

And, um, if you want to rewatch this course,

it'll be posted on i ame.com.

Um, you'll be able to re-watch the videos,

see the images, see the technique.

Um, whenever we, um, talk about anything, if you need a,

if you need a protocol

or something for your clinic, just reach out to me

and I can send that over to you.

No problem. Um, remember, diameter

of the nerve, architecture of the nerve, short axis,

long axis signs, and then if you just read about, read up,

read up on the characteristic points of impingement

and nerve problems

for all the peripheral nerves per each one

that you're gonna scan, you know, you don't have to do it

and know it ahead of time, just

look it up right before you go in.

You're gonna know that that protocol, you know,

for the median nerve, it's gonna be the carpal tunnel,

the pronator in the forearm, um, up in the proximal,

uh, or in the distal biceps area

where there could be a scoular spur, um,

or, you know, up in the, up in the arm where it's going in,

where there could be a mass or something like that.

So again, thanks everybody for coming tonight,

and this has been the Institute

for Advanced Medical Education i ame.com.

Um, monthly webinar will be here every month.

Um, and we will see you then.

These come included in your membership. Thank you so much.

Mastering Carpal Tunnel Diagnosis with Peripheral Nerve Sonography

Chapter 1