Lower Extremity Veins: Techniques and Interpretation - SD

Introduction

Hi, my name is Annemarie Kapinsky.
I'm from Albany, New York,
and I'll be speaking to you about venous duplex
ultrasound examinations.
This lecture will be on the techniques
and interpretation of lower extremity venous duplex
ultrasound examinations.

Methods to Assess Venous Disease

There are many ways to assess a patient for venous disease.
We can do a clinical exam,
however, this is not highly sensitive.
In fact, only about 50% of the time will we be correct,
by just evaluating the clinical signs
and symptoms of a patient.
There are other indirect tests involving CW Doppler
or various plethysmography,
but those have pretty much been abandoned for the use
of duplex ultrasound, which is our primary testing modality.
Although some folks will do occasional venography,
venography is still considered the anatomic gold standard.

Positioning Considerations

One thing to pay attention to when you're doing any type
of ultrasound is your position as well
as the patient's position.
Now, sometimes the veins are harder to see.
They're under low pressure, so in order
to make them dilate a little bit,
if you put the leg into a dependent position,
either reverse trendelenberg is shown here,
or having the patient sit upright
to examine the calf portion of the veins.
Either one will be a good method to
get some more pressure on the veins, have them
to stand a little bit more,
but understand that they will be under more pressure.
Therefore, they will need more pressure.
You'll need more pressure to get those veins
to completely compress.
And of note, to pay attention as you're scanning,
you wanna pay attention to your posture, how your arm,
elbow, wrist, and everything is aligned,
to avoid any work related injuries.

Scanning the Lower Extremity Veins

When we examine the lower extremity veins,
we pretty much start at the top
of the leg in the groin crease,
but we're really below the inguinal ligament.
The inguinal ligament sits just a little bit higher
from where we begin.
So we start at the common femoral vein just
below the inguinal ligament,
and we'll follow that all the way through the femoral vein,
the popliteal, and into the tibial level vessels.
One thing to note, remember,
we call this vein the femoral vein.
We no longer call it the superficial femoral vein,
even though it's the companion vessel
of the superficial femoral artery, we
have gotten away from using the term superficial femoral
vein to avoid any confusion as far
as treatment is concerned for thrombus in that vessel.

Vessels to Assess

So what vessels do we need
to assess when we do a lower extremity venous ultrasound?
Well, the documentation
that I've put together within this presentation
relies pretty much on the standards
of the inter societal commission for the accreditation
of vascular laboratories.
I-A-V-L. These are in compliance
with the I-A-V-L standards.
Currently, I'm less familiar with a ACR standards,
American College of Radiology,
but they're probably pretty similar.
And in terms of the vessels that need to be documented,
we again do the common femoral femoral vein.
We do the very terminal portion of the deep femoral
or profunda femoral vein, the great saphenous vein,
popliteal popliteal vein,
and then down into the calf, we look at the terminal portion
of the small saphenous as well as the gastrocnemius,
posterior tibial peroneal, and so veins.
Now, one vein that's not listed
here is the anterior tibial vein.
The incidence
of isolated anterior tibial thrombus is probably
less than half a percent.
It's very uncommon. I've seen it only three times.
And in each of those patients, they've presented
with symptoms along the anterior compartment.
So in the absence
of symptoms along the anterior compartment,
the anterior tibial veins do not need
to be routinely examined.

Procedure Details

The procedure is simple.
We use a transverse orientation
and we do compressions every two to three centimeters.
We'll rotate the transducer into a sagittal plane if we're
doing color flow evaluation or spectral analysis.
Here we begin again, we're at the top of the leg just
below the inguinal ligament,
and we see the common femoral vein here,
very large in the center, common femoral artery off
to one side, and the great saphenous vein off to the other.
And we always position this.
So the patient's right is actually on the left
of the screen here, and their left is on the right.
So it's like somebody standing in front of us,
this is their right, and over here is their left.
Some people look at this orientation
and have referred to this orientation as Mickey Mouse sign,
where Mickey's face is, the common femoral vein
and the great saphenous,
the common femoral artery make up his ears.
We go down the leg
and we document the compressibility of the vein.
Most folks will do a split screen image like this displays
where the left side of the screen is non compressed
and the compressed view is on
the right side of the screen.
This works very nicely for large vessels.
You can put in indicators, arrows as
shown here, but you don't have to.
And this is the convention of showing compressed
and non compressed views.
We'll continue down.
This slide is labels obviously added in
to show the superficial femoral artery and the femoral vein.
Again, the just femoral, not superficial femoral vein.
And here we can see the walls of the femoral vein collapsed.
One thing as we go down the leg,
we're usually on a medial approach onto the thigh here.
The femoral vein gets deeper and deeper,
and here it's not very deep.
It's only about four centimeters,
but it gets down into the muscle layer coming
through the adductor canal.
And at that point, it is actually hard
to compress from this view here.
So if you actually apply pressure with your free hand from
underneath, you can get that vein to collapse a lot easier.
Here we have also the calf veins can be a little bit troublesome to evaluate.
There is a lot of anatomic variation,
particularly in this region right here off
the popliteal vein.
We usually give rise to a common peroneal
and common tibial trunk, which goes just a centimeter
or two, and then splits again into paired peroneal veins
or paired tibial veins.
But this can be really very variable.
The length right here of this vein
or the common tibial vein could be fairly non-existent.
You may have the popliteal vein come down
and then just split into four branches being all the named tibial veins.
And here's ultrasound of the popliteal vein,
both non compressed and compressed.
Right here is what's left to the popliteal vein.
Remember, when we scan the popliteal vein,
we're using a posterior approach.
And from that approach,
the vein now sits on top of the artery.
The other thing to remember about the popliteal vein is
that very often it's a bi fed system.
I think perhaps about a third of the time,
some folks say it's more like 40 to 50% of the time.
The literature is pretty variable.
But be assured that there will be patients that will come
to you with two popliteal veins.
One usually does sit superior to the artery,
but a lot of times the other one is more inferior or
much deeper.
And you may miss it.
So it may be sitting somewhere over here,
and you may miss it.
It may be thrombo and hard to see.
So just try to look around
and make sure you have fully evaluated that popliteal area.
The other thing is to really get comfortable
with the rest of the anatomy.
Obviously we know the skin is at the top of the picture,
and we've got the subcutaneous tissue just below it.
But this bright white through here, that's fascia,
that's the loose connective tissue
or part of the connective tissue, I should say.
That wraps the muscle bundle.
And you see it here
and you also see a little bit of it underneath it.
And when we see vessels sitting inside that muscle bundle,
those are the muscular branches, either the, in this view,
we're seeing the gastrocnemius, veins, vein, artery vein.
There is a companion artery here.
If we see vessels that are coursing between the muscles,
those are the big veins like the posterior tib and peroneal,
and that's what this picture shows.
We can just about make out the edge
of this one muscle head right here.
You can kind of see the difference in the tissue
and a little bit of the fascial wrap here.
And here are posterior tibial vessels
and here are peroneal vessels.
So we have posterior tibial vein, posterior tibial artery,
posterior tibial vein,
and then peroneal vein, peroneal artery, peroneal vein.
Now the peroneal vessels used to be called fibular vessels,
fibular artery, fibular veins, because they sit right here.
Here's the fibula right down here in the corner.
They sit right on top of it, so that's why they used
to be called fibular, but we call 'em peroneal
and they'll be a little bit deeper just above the bone,
whereas the posterior tibs will be a little more superficial
and sort of just medial to the tibia.

Evaluation of Superficial Veins

Now it's an examination for a deep vein thrombosis,
but we do include evaluation of the superficial veins.
We've got here the a schematic
of the great saphenous vein.
We do wanna look at the termination
of the great saphenous vein into the common femoral vein.
Here we see an a sagittal orientation,
the great saphenous coming in
and emptying into the common femoral.
We see the superficial epigastric vein
in view in this image.
What we don't wanna see is A-G-S-V that looks like this,
where we can see this hyperechoic material,
which is thrombus extending right across the
saphenofemoral junction.
Depending on the circumstances, most
physicians would treat this as a DVT
because it does present a risk
for thromboembolism and pe.
Here is another view of the calf.
This is higher up in the calf.
We have the popliteal vein,
popliteal artery down near the bottom.
And again, if we look at the rest of the gray scale image,
we can appreciate the muscle head right here
and our gastrocnemius's artery and companion veins.
But what's important in this view is the small saphenous.
The small saphenous, of course, used
to be called the lesser saphenous or short saphenous.
And it sits way right up in like a fascial sandwich.
There's a piece of fascia above it and below it,
and not much tissue next to it.
So often the saphenous, the small saphenous is hard
to distinguish, and it is pretty small.
So we'd probably want
to even increase the transmit frequency in this case
and see if we can maybe decrease the number of focal zones
and move them up closer so we can optimize
that first centimeter or so of tissue depth.
If we're evaluating the small saphenous,
well image is important,
but when we talk vascular, we have
to worry about the doppler too.
And we do have to take doppler signals from
basically several major vessels.
You can do it from all the vessels.
I don't think it's really needed below the knee.
There are multiple calf veins, so if you're going
to Doppler, you really have to doppler all of them
because it's not all that helpful just
to document a doppler waveform from one of several c veins.
So we normally record spectral
doppler from the common femoral vein as well
as the popliteal vein.
Many folks also include the super, what we used
to call the superficial femoral vein.
Now the femoral vein, so it's common femoral,
femoral and popliteal.
Our kind of standard levels to document.
We record those doppler spectrums at rest
and also with augmentation maneuvers, either val Salva
or distal compression.
And there are many reasons why we may examine patients just
for one leg symptoms with one leg.
However, we need to record
a complementary contralateral common femoral
vein doppler signal.
If we're only doing a unilateral study,
this is a requirement by the I-A-V-L,
and it's a requirement
because when we examine these
common femoral vein signals bilaterally,
it'll give us a good idea
of what's going on systemically with the patient.
And we might be able
to detect things like systemic venous
hypertension or other problems.

Doppler Evaluation

So here's a doppler spectrum
where we've got our doppler cursor in the common femoral vein.
And you notice here the angle correction is on,
and it may actually appear on in several of the images,
but it is not necessary to angle correct for venous doppler.
But you still need to get a good angle in order
to get a good doppler shift.
So you will want to try to approximate your 60 degree angle
of insonation, but here we see flow
and then no flow flow, and then no flow.
And what happens is when we take a breath in
and inspire the pressure in our abdomen increases, well,
the pressure in the abdomen increases to a point
where it actually exceeds the pressure in
the common femoral vein.
So we basically shut down flow from the common femoral vein.
When we exhale, the pressure in our abdomen goes down,
it's now lower than the common femoral vein pressure.
So we see flow. Again, we should be able to see
that spontaneity and phasicity in the venous doppler signal down
through the popliteal vein.
That's pretty common.
You may have a little trouble with some
of the tibial veins if you are going
to do tibial vein doppler,
but you should see good spontaneous signals at least
down through the popliteal.
If not, take a look at your adjustments.
In fact, this PRF or scale is probably too high for a vein.
You might even wanna drop that down a little bit lower.

Color Doppler

Well, when we talk about ultrasound,
it wouldn't be complete if we didn't discuss color.
Now, color isn't essential.
You can get through a venous exam without it,
but it certainly is helpful.
It is still considered to be complimentary and not required.
However, it can aid in the identification
of the extent of thrombus.
We can use color to help locate a vessel,
finding the companion artery and using that as a guide.
And certainly there's areas where we can't compress a vein,
so we can use the color signal
to help confirm vessel patency.
But remember, just
because you don't see color, it doesn't necessarily mean
that the vessel is thrombosed.
And just because you do see color in a vessel doesn't
necessarily mean that the vessel is thrombus free.
That's very important.
It all depends on the settings of the equipment.
Now here we see, again, a femoral vein
and superficial femoral artery kind of getting deep in view,
and we're using the superficial femoral artery as our guide
to help us follow that femoral vein
Down in the calf here again,
we've got the subcutaneous tissue here,
we've got the gastrocnemius muscle on top.
That's the first one. And now underneath that is the soleus.
And this tributary coming out of the soleus muscle
coming into the posterior tibial veins is a soleal vein.
We aren't getting good filling in these
posterior tibial veins.
But remember, venous flow is dynamic,
and we've got a static image here,
and these vessels are perfectly patent.
It's just a matter of timing.
We are transverse to them, so that's a little bit more
of a challenge to create an angle
so we can get good filling.
But certainly color is very beneficial when
we have things like this.
Acute non occlusive thrombus with this tail sort
of swinging in the breeze in the blood flow
of this common femoral vein.
Color can help here as we see another bit
of thrombus at another patient.
In the saphenofemoral junction,
we can see while the thrombus does extend,
here's the saphenous out into the saphenofemoral junction.
We are getting flow around it
and a little bit of flow from the great saphenous,
probably from the superficial epigastric vein in fact.
And that'll help define where we see things.
Over here, we've got flow filling the popliteal artery
and one tributary vessel here,
but no flow in that popliteal vein.
Here's just a series of images of the same popliteal artery
and popliteal vein.
Now here is the popliteal vein.
You can see there's echogenicity within the vessel
and a very, very faint amount of color filling here.
In this next view, this is the exact same location.
We still see our popliteal artery,
but we're seeing a little more color filling
in another view, even a little more color filling.
And in this view, almost not really fulfilling,
but a lot more filling than we saw in the first image.
The only thing that was changed in these images was the
color priority.
This is a setting on all ultrasound systems.
They might have different names,
but it basically tells the system how much color
to write over the gray scale.
So if your color priority is high,
you'll get a lot more color filling in,
and it'll fill right in over areas
of non occlusive thrombus.
If your color priority is low, the software
of the ultrasound systems is going
to send much more power into generating the gray scale image
and not overlay very much color.
So you'll see more thrombus and less color.

Interpretation of Images

Normal Veins

Now what about interpretation of the images?
Well, normal vein should appear nice, smooth, thin walled.
You may see slight changes with respiration.
You may see some echoes,
but we usually set this up so that the lumen
of the vessels are pretty dark, pretty anechoic.
If we can see the valves, we may see some slight motion within the valves with blood flow
and the valve sinuses may appear elliptical.
And here's a picture.
Actually, this is an arm vein
where we can see the valve leaflets here
and here, a little bit of the insertion ridge,
this thickening here, which is part of the vessel wall.
And we have the valve open and valve closed.
And that's just during normal breathing patterns.
Sometimes though thrombus does happen behind valves.
And here's a valve that's sort of stuck out,
frozen out into the lumen with lots of thrombus behind it.
And that thrombus has propagated
and extended into the lumen of the vein,
and certainly represents a risk to the patient
once we find thrombus.
The other thing we need to do is characterize it
as being chronic or acute.
Some people use a third categorization of subacute.
But for the purposes of today's lecture,
we'll just talk about acute and chronic.

Acute Thrombus

Here we have an artery in a vein, artery in a vein,
non compressed and compressed.
And we can see that we're not getting compression on this vessel.
We know that it's thrombosed.
When we take and document these images,
we can certainly do whatever we want.
We can include labels and arrows.
I think cine, small cine loops three seconds
or so, are extremely valuable for the tibial level veins
that may be small and difficult to image well
with a still image.
When we find acute thrombus, the thrombus is brand new
or relatively new.
There's a lot of liquid plasma still within that clot.
So that thrombus may appear spongy
or deformable with ultrasound transducer pressure.
The thrombus itself may be echoic or hypoechoic,
but you can't rely on the echogenicity alone.
It may be poorly attached. We may see a tip or tail visible.
The thrombus itself will have smooth borders
and the vein will be dilated
because what happens is as the thrombus starts to form,
that creates an increase in venous pressure more
distal to the thrombus.
That vein will dilate
with the increase in venous pressure.
So the vessel will be quite dilated with acute thrombus.
And here's an example of that. Here's an artery up here.
Here's the vein. And you can see
that the vein is very dilated compared
to the companion artery, but relatively anechoic,
and that's consistent with acute thrombus.
This image I showed a few minutes ago of
a thrombus here in this vein.
But let's pay attention a little bit closer to some
of the information here.
We have the artery in this view
where it's being compressed is actually being
slightly compressed itself,
and it's turned from a relatively circular artery into
more elliptical artery.
But the vein has changed as well.
We have a relatively circular vein here,
and the vein has become more elliptical.
That's because it's new and it's what we call spongy.
It's deformable. Of course, when we see images like this,
we know that we're dealing with an acute thrombus.
Again, real smooth on the borders.
And this tail or tip, sort of just extending into the vessel lumen.
Here's another image of an acute thrombus.
And I think if you look at this quickly,
you can again distinguish up here the muscle bed
and these vessels in the muscle.
There's the gastrocnemius artery.
There's one vein and there's the other.
And this is probably a good four
or five times the size of this vein.
So it is dilated.
And if we were even to look a little bit closer,
I think we can see the edge
of the thrombus here a little bit.
There's a little bit of echoic lumen.
It's relatively smooth, so we have something that's dilated,
relatively smooth, anechoic, all characteristic
of an acute thrombus.

Chronic Thrombus

Now, when we get chronic thrombus,
chronic thrombus is rigid.
It's firm, it's hard, it's been there for a while.
The liquid, the plasma has been reabsorbed.
When that liquid gets reabsorbed, all we're left
with is fibrin and some dead cells.
But this is all attached to the vessel wall.
So as the clot itself constricts
or contracts, because the water's being reabsorbed,
the plasma is being reabsorbed, that
clot actually pulls the walls of the vein with it.
So the vein now looks constricted or contracted,
and is smaller as compared to its companion artery.
The walls of the thrombus, the edges of the thrombus,
I should say itself look irregular.
Maybe hyperechoic the vein walls too.
And we may see collaterals.
And here is a good image of a chronic thrombus.
Here's the artery, here's the vein.
We can see mixed level echoes here,
and a vein that's just about the same size
as its companion artery.
Here's another view of chronic thrombus
where we see this tail.
This just fibrotic material where we have a vein here
that's about the same size as the companion artery,
and again, some chronic residual thrombus.
So to compare and contrast, generally spongy, smooth surface
dilated versus rigid,
irregular surface contracted.
Those are some of the key characteristics between chronic
and acute thrombus.

Venous Doppler Signals

In terms of the venous doppler signals,
venous doppler signals from the lower extremity should
display these five characteristics.
It should be spontaneous,
it should be phasic with respiration.
It should cease with proximal compression
and augment with distal compression
and should be unidirectional towards the heart.
This is a little bit different in the upper extremity,
but for the lower extremity,
these five things should take place.
Here we have two examples of venous doppler signals.
On the top, we see nice phasic flow on the bottom,
we see phasic flow as well, but we've got flow
and then no flow flow and then no flow.
But we're seeing a little bit
of superimposed pulsations here.
This is just transmitted cardiac pulsations.
It does not represent true pulsatility.
As we are getting cessation of flow in
between these breaths, augmentation,
we should see this augment.
When we do a squeeze, when we do a val Salva,
we should see the flow stop.
And those are all important images
to document when we're doing our doppler signals.

Abnormal Doppler Patterns

Well, what if we don't find that in our doppler signals?
What if the doppler signals are slightly pulsatile?
Well, if they're pulsatile
and their pulsatile bilaterally, this is an indication
of systemic venous hypertension.
There's a lot of things
that can cause systemic venous hypertension, right?
Heart failure, tricuspid insufficiency,
pulmonary hypertension, any of those things
can be present
and will create pulsatility within the venous side.
Most folks don't get into things too specifically other than
noting that there's pulsatile signals bilaterally at the common femoral veins.
And you can add in something like it's suggestive
of systemic venous hypertension
or indicative of systemic venous hypertension.
Now, if you only get a pulsatile signal on one leg,
it's probably because there might be some sort of a AVF
or arterial venous fistula Present could be
congenital traumatic iatrogenic.
Any of those will give you a pulsatile signal.
These two types of pulsatile signals differ just a little
bit, but they are going to be something similar to this.
This is in a patient with systemic venous hypertension
where we're seeing beep beep beep.
And if we were to move into the companion artery,
we'd see the same type of rhythm placed within that artery.
Kind of mimicking the venous rhythm here.
Well, if we get a continuous doppler signal
that's equally abnormal on one leg, we have
to think what's going on with that one leg.
That would create a continuous doppler signal.
A continuous doppler signal comes about
because the pressure in that vein is now increased
and it's increased to a point
where it's exceeding abdominal pressure changes.
So what can increase the pressure in that vein?
What can back it up?
Well, partial DVT or previous DVT
or intrinsic venous compression,
or extrinsic venous compression will also produce a continuous doppler signal.
If we see a continuous doppler signal bilaterally,
then we have to think further centrally
and that the IVC may be involved either with thrombus
or extrinsic compression.
And here we see a common femoral vein
with a continuous doppler signal.
But we know there's something wrong here.
We see all this thrombus within the vein.
So we have a partial thrombus.
That partial thrombus is not letting all the flow through.
The flow is backing up, it's increasing the pressure
and it's producing this non phasic doppler signal.

Case Study: Outflow Obstruction

Now we have a couple of examples here
to illustrate some of these points.
This we have a couple images here from a 63-year-old
female who is presenting with left lower extremity swelling.
She's a hypertensive, non-smoker, non-diabetic,
and all the veins were found to be fully compressible,
but this was the Doppler signal obtained.
So while the doppler signal is not phasic,
it is in one direction,
the veins are compressible.
But what could be the going on with this,
with this area here?
Here's another image where again, fairly straight
and we see some augmentation.
Things don't get any better when we look distally.
Here's the proximal thigh portion of the femoral vein
and the distal thigh portion of the femoral vein, not
what we would expect for venous doppler signals.
And here's the contralateral leg
actually almost appearing pulsatile here.
So what's the best explanation for these signals?
Can we say this is a normal study with no evidence of DVT?
Probably not.
While there's no evidence of DVT,
those doppler signals are not normal.
So we have to report on them.
Are they consistent with a patient
who might have an arterial venous fistula?
Are they consistent with a patient who might have some sort
of outflow obstruction
or are they consistent with a patient
who might have systemic venous hypertension?
Well, we've ruled out A, B
and D are almost going to give us the same sort of answer
in terms of what we would expect to see on the image.
And that if we have a fistula
or if we have venous hypertension, we'll expect pulsatility.
We did not see that on the left leg.
So we examined this patient further up,
we went up into the pelvic region
and sure enough, here's the external iliac vein.
Now it's compressed down. We see this mass.
And sure enough, it was outflow obstruction due
to extrinsic compression.
The left external iliac vein was being compressed
by this pelvic mass,
and the patient went on to get a CT to further delineate what that pelvic mass was.
But we can see this highly abnormal
external iliac vein doppler signal.

Reflux Evaluation

The only other thing that we should think about when we talk
about doppler in the venous system is reflux time.
The topic
of venous insufficiency is a whole nother lecture,
but just know that we can look at veins,
we can look at color, we can measure vein diameter.
We also need to measure the reflux time
with the spectral doppler.
And in this case, we're here at the Saphenofemoral junction
and our reflux time is all approaching three seconds here,
2.7 seconds.

Case Study: Varicose Veins

Now here's another case where we have a female, again,
57-year-old who's presenting
with varicose veins along the medial aspect
of her left thigh.
She has really no major history of any kind, non-smoker,
no hormone treatment, no history of DVT.
So we begin the exam at the Saphenofemoral junction
And we see that there's flow on color
and we see some flow on doppler
and we see the flow stop, kind of a little,
this is a little bit of noise.
This is normal valve closure here.
But as we go down the thigh, we can see all
of a sudden here now we've got a different story.
If we look at the color flow, image
flow towards the transducer should be in blue.
Flow away is red. This is color coded in red.
If the heart's up here
and the feet are down here,
this is flowing towards the feet,
so it's flowing in the wrong direction.
And that is displayed here in the spectral Doppler as well.
We see the antegrade flow up towards the heart
and then this is retrograde flow falling back down several
seconds worth, probably close to three seconds worth
of retrograde flow in this evaluation.
But going further down the thigh,
we see this image.
Now we've got blue, blue is away.
This is angled in this direction.
So flow should be away from the transducer
back up towards the heart.
And what's going on with this patient?
Well, was there incompetence at the saphenofemoral junction?
Sorry, extending all the way through the thigh.
Well, we didn't show really incompetence at
the Saphenofemoral junction.
Was it competent there
and then the remainder of the GSV incompetent?
Well, not really,
because in that last view, we saw some degree
of competence in the great saphenous vein.
So it's just the mid portion of the GSV incompetent
and the remainder competent.
Well, if you look very closely,
we actually could find the point at which
the reflux was occurring.
So we had competent vein up here,
but then we had a large tributary coming in.
Could have been fed from a pelvic vein or
some lateral accessory system
creating incompetence through the middle of the thigh.
And then another large lateral accessory
or anterior accessory system that was taking
that pressure gradient out.
So the remainder of the GSV was competent.
This is important because it actually will determine
what kind of procedure a surgeon may
or interventionalist may want to do on a patient like this,
being that we had competent segments,
but large incompetent areas as well.
So yes, for this patient, the mid thigh GSV was incompetent
due to an incompetent accessory system,
but the remainder of the GSV was competent.

Non-Venous Pathology

Now, not everything that we see on ultrasound is going
to be pathology that is the result
of some abnormality within the veins.
Remember, we can be faced with patients
with arterial aneurysms, cysts, hematomas tumors.
And what will happen if we see these things is that
these large structures can often compress the vein
extrinsically, again, increasing the venous pressure leading
to some edemas pain, decrease in flow,
which actually can result in A DVT.
But sometimes we have no DVT
yet we see this non venous pathology
as in this case here we have this large mass that's sort
of tracking down, not too deep on the leg,
but sort of extending down a good portion
over the head of the gastrocnemius muscle.
We can see that whatever it is, it's kind
of pointy at the edges
and we are definitely getting posterior enhancement
of the doppler signal.
So what could that be?
Well, it actually is a ruptured baker cyst,
or more correctly a ruptured popliteal cyst.
Not every cystic structure in the popliteal fossa can be
called a baker cyst.
Baker cyst have a unique configuration where they travel through
the musculoskeletal features
of the popliteal fossa.
But we can appreciate the cyst,
we can appreciate the posterior enhancement
a little bit here in a greater way here.
Sometimes the cysts have this mushroom like appearance
where again, you kind of see the head of the mushroom,
the cap of the mushroom and the little stem
or tail kind of coming down into the popliteal fossa.
When the cyst rupture, they kind of will take the path
of least resistance, of course.
And what happens with the cyst is they'll kind of,
that fluid will sort of divide
and tear down along that fascial boundary.
So rather than having a more rounded appearance,
you'll have a pointy appearance to the edge here,
very consistent with a ruptured popliteal cyst.
Now many folks are trained to read vascular ultrasound.
Some are trained to read general ultrasound as well
as vascular, have a good appreciation
of skeletal muscular features and other things.
But if you're not sure about what you're looking at
and you're not really well experienced enough to
read nonvascular pathology,
your documentation should just include the size
of the structure, the heterogeneity of the structure.
Could you compress it at all
and was there any blood flow present?
Those are all important features to be documented
when we run across some nonvascular pathology.
Here's an example where we've see this large mass in the
popliteal fossa and we put color on,
and we can clearly see that it's being fed with several
flow channels here.
And this it represents actual tumor.
This patient had metastatic cancer.

Conclusion

So to conclude, ultrasound can easily be used
to determine patency of a vessel
and confirm the patency of the vessel.
It certainly can be used to identify the pathology.
And if we have thrombus, whether it's acute
or chronic, we're gonna use our venous doppler patterns
to help us figure out what's going on within the vessels
that we're looking at directly, as well as
what could be going on remotely, say as up into the IVC
or the pelvic veins.
And we must thoroughly document our findings
as our lab protocols dictate.
But if we can't, then we definitely need
to know any deviations thereof.
Thank you very much.