Upper Extremity Venous Thrombosis - SD

Introduction to Upper Extremity Venous Duplex Scan

I am Gail Hadley, the technical director
of the Vascular ultrasound core Lab at
Mass General Hospital.
This presentation is going to discuss how
to conduct an upper extremity venous duplex scan.

Incidence and Risks of Upper Extremity Venous Thrombosis

Upper extremity venous thrombosis is more common
and less benign than previously thought.
Originally, most patients were asymptomatic
and there were no screening exams to look
for upper extremity venous thrombosis.
Actually the incidence is much higher
than originally reported.
Approximately 10 to 30%
of upper extremity thrombus will cause pe,
and this is from generally the central veins.
The incidence of central vein thrombus is doubled in those
patients who present with symptoms.
So if you have a patient that comes to the laboratory
and has symptoms for upper extremity central vein
thrombosis, it is more than likely
that the scan will be positive
for some central vein problem.
The relative risk, as just mentioned, pulmonary embolism,
venous hypertension,
and this is particularly a problem for those patients
who have dialysis access grafts in their forearms.
If you have a dialysis access graft
and you have central vein thrombosis
or occlusion, you could have the problem
with this added burden of volume of flow
into the central veins.
They can't handle the volume
and then it just goes into the tissues
and the patient's arms become extremely swollen
and actually is life altering for these patients.
Then there's a huge problem with no axis.
If you've occluded your central veins
and you depend on a fistula for as your lifeline,
then you have limited your options for further dialysis.
So therefore, it's very important to be able
to accurately identify the absence
or presence of central vein thrombosis.

Factors Contributing to Upper Extremity Venous Thrombosis

Factors that contribute to the problem.
Central venous catheters, 70% of those patients with set
with central venous catheters can actually have central vein
problems, stenosis or thrombosis.
If you add malignancy to the patient
that has a central vein catheter, the
percentage actually goes up.
Then those, those patients, usually younger males
that have physical functional impairment
and that's called pageant schroeder.
And what happens is at the thoracic inlet
where you have your veins, your arteries, your nerves that
during certain motions, the first rib will actually cause
compression of some of these structures.
And if they do some sort of occupation
where they have repeated compression of the vein,
it will set up an area for thrombus formation.
And you see this a lot in athletes baseball, people
who continually are doing the same motion
over and over and over again.
IV drug abuse, radiation induced thrombosis,
extrinsic compression generally from masses
that are found in the chest
and congestive heart failure symptoms include pain
and swelling, dilated superficial veins
and these dilated superficial veins are generally seen
anteriorly across the chest catheter problems related
to dialysis.
If it's on the ipsilateral side to the problem,
the patient's dialysis might have some changes occurring
because of the obstruction in the central veins.
Peripheral thrombosis is generally a clinical diagnosis
and this is seen by a palpable cord.
Usually it's red, it's warm,
and this is often occurs from IVs.
If you need to scan these patients,
you would just scan the vein in question
and follow to determine the specific location and extent.
This presentation is going
to focus on the upper extremity central veins.

Equipment for the Scan

The equipment to conduct the scan includes a small
footprint transducer.
This is your best option
because of all the bony structures, the clavicle
and the shoulder.
It is helpful if your footprint is very small
so you can get into some of these smaller spaces
and be able to manipulate your beam.
Variable transducer frequencies are helpful.
You're scanning anywhere from very superficial looking at
the IJ down to the deeper depths of the denominate vein.
Now, most often you will not need to change frequencies,
but you should entertain this thought.
Should the image quality fall off acoustic gel, it is good
to keep sterile acoustic gel around.
A lot of these patients with central venous catheters
will have coverings
and it's very, very important not
to contaminate the catheter.
And so sterile gel and
or at tegaderm over the actual catheter
site needs to be placed.
Before you can conduct your scan,
you need a recording device
and as noted, the sterile coverings.
And here in the image you can see
using a sternal notch approach, which is reserved
for maybe when you have dressings
and can't see from the infraclavicular
and supraclavicular approach,
but you can actually see both a nominate veins joining
to see the superior vena cava.
This isn't usual because the superior vena cava
is rarely seen.

Protocol for the Exam

Now the protocol to conduct the exam you need
to conduct a bilateral exam, you need
to examine the internal jugular vein, subclavian vein,
a nominate also known as the brachial cephalic veins,
axillary vein, superficial veins, cephalic and basilic veins
and the peripheral veins are added when necessary.
Now, to identify the central veins correctly, you need
to understand the anatomy
and the spatial relationships to other vessels.
And looking here at the anatomical image, we have the IJ
as it comes down to the confluence of the innominate
and the subclavian.
Then we see the subclavian vein,
the more central portion here.
Then we extend out to the peripheral portion,
and this is where we run into the clavicle
and this portion of the vein cannot be visualized
and that is one of the limitations
of upper extremity venous scanning, the inability
to see all vessel segments.
Then we come out to the axillary vein.
And for this, because of the bony structures, again,
here's your clavicle,
you're gonna use the infraclavicular approach to be able
to access and get a clear image of the axillary veins.
Due to the location of the axillary vein
and the ij, we are actually able
to use compression maneuvers where with the subclavian vein
compression maneuvers are not possible due to the clavicle.
As we continue on down with the anatomy, we come out
of the axi and then we have the cephalic vein
and we have the axillary vein confluence
of the basilic vein.
Now the cephalic
and the basilic are your predominant veins
of the upper extremity arm,
even though they are superficial veins.
This is unlike the lower extremities
where the deep veins play the predominant role.
Now there are numerous collateral pathways
to the upper extremities
and it's important to be aware
of these pathways even if you don't understand
or know the name of the vessel,
that the upper extremity in the presence
of occlusions collateralize very rapidly.
And when this happens, these collateral pathways take over
and you can see the relationships in this diagram here.
If this were occluded the internal jugular vein,
then your external jugular vein might take over
and you might see some directional flow changes.
You might see some size changes,
but most importantly is you're gonna see a different
relationship of this vein to the calm and carotid artery.
So one should always suspect when the internal jugular vein
is not seen a line next to the common carotid artery
that they might in fact be next to one
of the collateral vessels or the external jugular vein.
Anatomic anomalies are rare in the upper extremities,
unlike the lower extremities
where you often have duplicated systems, absent vessels,
that is rarely seen in the upper extremities.
Anatomical considerations as I noted
before, superior vena cava is very rarely visualized
and you can indirectly make a diagnosis
of superior vena cava syndrome if you see
diminished flow from both a nominate and
or subclavian veins.
The innominate vein complete visualization is limited
and depends upon each individual's anatomy.
The axillo subclavian veins
are visualized only partially due to the interference
of the clavicle.
Multiple approaches required here, infraclavicular
and supraclavicular to try
and actually get around the bony interference.
You have limited compressibility due to the bones
and it's also prone to artifact from bone and lung.
And here we actually have the
left innominate vein.
Here we have one of the referenced landmarks.
It's the internal mammary and you can see the pleura.
Again, something that will cause
artifact During our scanning.

Technique for Scanning

The technique, the patient should always be placed supine.
They should be comfortable the exam is bilateral.
You use both a supraclavicular and infraclavicular approach.
Here we're looking at the axillary vein
and we're assessing it.
The clavicle runs this way
from the infraclavicular approach.
You can also access the axillary vein by coming up
through the axi and aiming up towards the clavicle.
This can be used to identify
and get a second view of the axillary vein.
Now you should always do a brief clinical
assessment for the patient.
This can be very helpful in identifying
where the problem might be.
And in this particular patient we can see
that this patient has had previous indwelling catheters
by the scarring here.
So even if your patient can't give you a history,
you should always assess the patient for any
marks from previous lines.
And there's also, it's difficult to see in this image,
but you can look at the IJ here.
There is definitely some prominence
of the superficial veins.
All of this is classic for a patient
with central vein obstruction.
If you look at the size of the arm,
this is the normal referenced arm
and this arm appears we have whole limb swelling,
which is about twice the size
of the contralateral asymptomatic arm.
Now in the lower extremity,
compression maneuvers are most helpful
and the number one primary method of diagnosing DVT,
the image plays a secondary and complimentary role
and doppler as well.
While the upper extremity compression is limited
and not dependent upon for the diagnosis of thrombosis.
So you need to employ several parameters
that includes your image, color, doppler
and spectral doppler.
Here we have a patient that meets all of the criteria
for a positive study.
Here's the wall of the, out here we have the axillary.
Here is the most central portion of the subclavian vein,
and here we can see the echoes consistent with thrombus.
We have a narrow lumen so it's not totally occlusive.
The vein is dilated
and somewhat distended consistent with acute thrombosis.
And then we have our last component in the one weighted most
heavily the spectral doppler wave form.
And you can see that this is a dampened wave form.
The other side is completely normal,
so this meets the parameters
and is very highly accurate for the diagnosis
of central vein thrombosis when all three
parameters are a match.
But you can use compression in certain vessels
and it should be employed when possible Use color doppler,
but it does need to be optimized if you do not
optimize your color, you risk getting color overwrite
of soft echoes, which could be consistent
with intraluminal thrombus.
If you can't compress certain segments,
you can use the sniff test.
The sniff test is just a minor method of being able
to create pressure changes within the thoracic cavity
and see if there is a response to that in the veins,
just like using val salvo in the lower extremities.
So as the patient takes a brief sniff an inspiration,
you'll actually see the size of the vein gets smaller
and then you have a brief augmentation of flow.
This would be normal response to the sniff test indicating
that there is no obstruction anywhere from
where you're sampling to the more central portion
of the vein.
You should explain the procedure to the patient
so they can assist you
and make sure that they take a significant sniff in order
to create enough of a pressure change.
Always compare spectral waveform side to side.
So if we look at the sniff test,
you can see the augmented flow upon inspiration
and then upon release we go back
to the normal pulsatile signal.
But in this particular case, we have a normal limb
and then we have a dampened waveform on the
contralateral side.
This would indicate that this would be the arm
that we would look for central vein thrombosis.
So compression when possible, not only assessing
for doppler changes that occur during the sniff test,
but also assess for vessel wall motion, A vessel
that is patent and close to the heart.
You'll actually be able to see the vessel wall motion
during the changes in the cardiac cycle.
And respiration always assess for flow direction.
Here's the optimized color, allowing us
to see the residual lumen
and at the same time allowing us
to see the gray scales associated with the thrombus.
Here's the compression used for the ij.
We have the CCA in a transverse view
and compression of the ij.
Here's the ij, not compressed.
Extrinsic compression flow direction.
Color is a great method
to quickly identify if flow is normally directed.
Here we have the CCA going up towards the head
and the internal jugular vein going the opposite direction.
This is a very quick method
to identify correct flow direction within
the internal jugular vein.
Ultrasonic windows include supraclavicular infraclavicular
and it's always helpful when you find an abnormality
to confirm these findings from multiple views.
Due to the numerous artifacts that can occur from bone
and pleura, it is important to make sure
that you're not calling an exam positive for an artifact.
Here you can actually see the confluence coming from this
approach down into the denominate from the subclavian.

Components of the Study

So three phases to this study.
There's the image component, the color doppler,
and the spectral doppler.
Unlike the lower extremity,
that's what's weighted more heavily.
Here we have our image
and in a longitudinal view you can see the outline
of this thrombus.
The edges are very smooth, the vein is slightly distended,
and this is very consistent
with an acute deep vein thrombosis.
We come here from another view
and you can actually again see how dilated this vein is.
The walls are actually being pushed out a little bit,
again consistent with acute venous thrombosis.
Here we have the ij, completely normal in a transverse view.
Colors optimized nicely,
and here we have our normal spectral doppler
where you're seeing the pulsatility associated
with the close proximity to the right atrium.
Now a normal study as we move out to the subclavian
and then axillary vein, you can see here the clavicle.
This is medial, this is lateral color nicely outlines wall
to wall, a very widely patent subclavian and axillary vein.
When we move a little more central,
you can actually see we go from the subclavian down into the
an denominate vein.
You'll see the change in the depth of vessel.
Here's the associated doppler waveform.
Again, very pulsatile and phasic.
This ity is also
consistent with a normal exam.
Here's puls ity coming from a little bit different angle
from a more central portion of the subclavian vein.
Now these waveforms are both normal in spite of the fact
that to the native eye they might appear
to be somewhat different,
but they have all the components of a normal waveform.
Abnormal doppler waveforms are consistent with a loss
of the pulsatile variation
and you might actually still have ity,
but the pulsatility would be dampened continuous signal
absent, reversed flow, asymmetrical signals
or a stenotic jet.
And this is not uncommon
to have stenosis developed from the scarring
that occurs from having the central venous catheter.
Now the accuracy improves when all three
components correlate.
Here in the image we can see the subclavian thrombus.
Gray scale echoes very, very dilated vein
actually pushing out a little bit here consistent
with an acute process.
Here we can show the residual lumen in color
and then we come over and verify the waveforms.
The waveform at the site of the thrombus is dampened.
When we go to the contralateral segment
of the same subclavian vein, we find a normal
phasic pulsatile waveform.
Here's the correlating venogram.
This is a patient with pager schroeders
and this you can actually see the thrombus extends into
the cephalic vein.
Now other components consistent with an abnormal study
beyond the spectral doppler, any segments
that might be incompressible, the presence
of intraluminal echoes vessel size, wall motion,
color filling defects.
Now spectral doppler, if it's abnormal
but the image is not adequate to identify the pathology,
then you must include this in the report
that the doppler signal is abnormal.
However, the etiology is not clear subclavian
and a nominate thrombus, this is not an unusual location
for a patient with a central vein catheter.
As we're coming from the peripheral portion
of the subclavian, we see the thrombus
moving centrally down into the denominate.
So we have the positive doppler signal positive image.
Here's a patient where we can see the cephalic vein,
subclavian vein, and this is actually a collateral vessel.
If we go out here, we have more collateral vessels.
They don't show up very well in this image,
but this is all we could get.
This patient had an extremely swollen arm
and chest actually that extended up into the neck.
But based on this finding alone,
because of the severe venous hypertension,
this patient went on for venography to determine treatment.
Here is the axillary vein only a small segment
of the vein was visible with very, very abnormal flow.
And then upon venogram we see that this
is completely occluded.
Here's all the collateralization taking effect.
This patient had a proximal
arterial venous fistula causing increased pressure and
therefore visualization of all these collaterals.
This is why the scan was extremely difficult
because these vessels had no flow
and were essentially absent.
They treated the patient with lytic therapy trying
to open up the vein
and upon the first scan post-treatment,
you can see we did restore flow.
Color shows a little bit of the residual lumen,
but this is a good example of someone with chronic scarring
because we have sort of irregular walls here,
you can see the size of the vein.
It's not distended
and this is causing a continuous flow signal.

Findings for Innominate Vein Occlusion

Now for an included in nominate vein,
the classic presentation
or the classic finding would be
reversed flow in the internal jugular vein.
So if that one is suspecting an occluded in dominant vein,
it's best to go right to the ij,
put your transducer down low in the neck,
look at the common carotid, the associated ij,
and quickly one can notice
that they are both flowing in the same direction going
towards the head.
Now if we examine the remaining central vessels,
what we see is here's the subclavian vein.
Subclavian flow is directed towards the denominate.
When it gets here, it hits the occluded denominate
and it starts to reverse up into the internal jugular vein.
Even if you don't get this image here, the finding alone
of the reversed flow in the internal jugular vein
is consistent with a nominate vein obstruction.
And here we can see the correlating venogram.

Acute vs. Chronic Thrombus Findings

Now findings for an acute thrombus free floating,
it actually expands or causes distension of the vein.
The walls are smooth
and it appears to be like jello
where it's actually somewhat deformable for chronic changes
or scarring of the vein.
The size, it's gonna get smaller, it's going to,
the thrombus will actually retract or the scarring.
It becomes very firm. The borders are irregular.
You might actually see syn eye, which is just sort
of threading that occurs throughout the vein from the old
scar and or you might develop a stenosis.
Here is the image
of the chronic one that we looked at earlier.
Again, just showing the irregularity, the retraction.
And if we compare it to a more acute process,
the vein size is relatively small.
Now here we see a totally occlusive thrombus.
We see it's free floating.
The edges or the tail of the thrombus are smooth.
And if you could see this in real time, you'd be able
to appreciate the how easy it is to deform in the movement
of the actual thrombus.
That's consistent with an acute thrombus.
Here we have a small little chronic nub along the wall
and this is from a patient
who had a long-term indwelling catheter.
In the subclavian vein, this particular patient we have
old here's sort of the signy eye.
You can see along the wall. That's the old thrombus.
But when we look at the size of the vein,
it's somewhat distended
and you can't really appreciate the soft echoes here,
but that's actually pushing the walls out.
So this is a patient who has
new acute thrombus overlying an old event.
This is not always readily that easy to identify

Assessment of Catheters

Catheters, as we know, catheters tend to be the culprit
and often you need to assess a patient
with the catheter in place.
Now all the catheters will develop sort of a fibrin sleeve
or sheath, and one needs
to know when we advanced from the sheath to actual thrombus.
Here we can see the catheter, which is a specular reflector.
So depending upon how your ultrasound beam
hits the catheter, you may see it in some
views and not in others.
This is a normal catheter.
You can start to see some sheathing here.
And you can see though that flow is essentially normal
around the catheter and the lumen of the vessel
is completely free of thrombus.
As we move to another view of a different catheter,
here we have the triple lumen catheter sitting
out in the center of the vein.
Here we have the thrombus
that's actually attaching the catheter to the wall.
This catheter remained functional
and this was actually unchanged
during the patient's stay here.
We're looking at the same catheter,
but you can see the color nicely
identifies the patent lumen.
We come from another catheter
and this one is actually causing a problem
because you can see the distended vein, all the soft echoes.
This thrombus has totally occluded the vein pushed the
catheter up against the wall,
so the catheter is currently not working.
This catheter had to be removed.

Identification of Venous Stenosis

Now upper extremity venous duplex can also identify
venous stenosis.
The most common site is the confluence of the IJ
and the subclavian vein.
The focal increase in the velocity comes from the narrowing
of the vein caused by the actual scarring.
Now this image is not a very good image because this is low.
It's coming just from the most central portion
of the subclavian vein
around the curve down into the an
denominate on the right side.
And we're getting a lot of color override
and flash simply
because the velocities were
so high at the site of the stenosis.
This is very focal.
So you need to walk your sample volume around
through the area or open it up so
that you can actually identify the stenosis,
which is reflected here in the high velocity below.
This is actually the dampened signal.
So when you're not actually in the stenosis, you can see
that it's causing very,
very diminished flow everywhere else.
Here's a stenosis that's actually caused
by pro pressure of the ij.
It's very important to not mistake this for a stenosis.
Now a heavy hand usually doesn't matter for most
of the vessels,
when when we're talking about the central veins,
but it does play a role when we're looking at the IJ
and sometimes depending upon a patient's size out towards
the axillary vein, the artifacts
that you might encounter occurring from bone pleura
and lung mirroring.
Here we have an image where we have a mirrored artifact,
we have reverberation come tail effects.
Here we can see the au and noise.
You want to check your power levels
and you also wanna make sure to minimize some
of these artifacts to come from a different approach.
And by changing your intonation of the ultrasound beam
to the vessel, you might actually be able to work
around the artifact.
Now, if the artifact is continually there,
and no matter which approach you use,
you can see the artifact.
It's important to note that if you had thrombus,
the location of the thrombus won't move.
While with an artifact coming from different views,
it might actually appear to have moved.
And this is just sort of a little method of being able
to identify artifact from thrombus.

Pitfalls in Upper Extremity Venous Duplex Scanning

What are the pitfalls
to upper extremity venous duplex scanning the limitation
of ultrasonic windows.
Not all vessel segments can be completely visualized.
The presence of numerous collateral vessels,
short segment occlusions can be missed,
especially if they occur like under the clavicle.
Thrombus aging is difficult,
but that's generally due to the poor image quality.
The denominate vein, being able to identify mural thrombus,
that's just due to the location
and it can often be out of our field of view.
You must have the appropriate transducer trying
to scan the central veins.
Using a linear transducer will not provide optimum results
and limited compressibility of the vessel segments.

Summary

In summary, it's not as accurate
as lower extremity venous duplex scanning.
However, with the use of multiple parameters
to diagnose thrombus, you can accurately
identify the absence or presence of central vein thrombosis
or occlusions.
It is a challenging an exam,
and in order to produce good results,
you need an experienced examiner
and always obtain correlative studies
so you know if the scans you're doing
an interpretations are correct.