Test Your Waveform IQ - HD

Introduction

Hello, my name is Deborah Rubins.
I'm from the University of Rochester.
And today I'm gonna show you some unknown cases with doppler waveforms to test your Waveform iq.
And we'll look at arteries and veins and maybe some things in between.
With that, we'll get started.

First of all, neither I or any of my family have any financial relationships.
So nothing to disclose.

Case 1: Deep Venous Thrombosis Study

We'll start with the first case and this is a patient referred for a deep venous thrombosis study.
And the question is, what's wrong with the waveform on the left?
And you can see here's a normal right sided waveform.
Here's the left waveform, and you can see that there are these little peaks in it, and it looks like it could be in arterial venous fistula.
So my question to you is, is it or is it not?
And how can we tell? So we took some more images.
You should go back in and you can see here it looks a little bit more like a normal waveform, but you can see the artery here, aliasing behind it.
Here is the common femoral artery, which is in a separate plane.
You can see the normal arterial wave form.
So how are we getting the arterial wave form appearing in this vein?
Is there really a connection? So what can you do?
Well, you wanna look side by side.
And you can see here the artery and the vein are very close, but there actually is no connection between them.
And what we're seeing here, actually we can reproduce a very normal waveform in the left common femoral vein as long as we put our cursor in the middle of the vessel and not too close to where this artery is.
So this is a partial volume artifact.
It's not an AV fistula.
So you need to be careful and make sure that you've got good technique.

Case 2: Carotids in Syncope Patient

Here's another sort of example of the same point here is a patient who has syncope.
We're looking at the carotids here.
And the question again is what's your diagnosis?
And we can see a normal waveform here in the right common carotid artery.
And in the mid ICA, the waveform looks relatively normal.
The gray scale looks normal.
And in the proximal ICA, there's a very bizarre waveform with this little hump and a spike in the middle of it.
But there doesn't seem to be anything going on in the center of the vessel, at least on the gray scale, there's no plaque.
When we looked even further up in the right ICA, the waveform got even more bizarre.
So again, what can cause this bizarre waveform?
Do you have somebody who's got some kind of a strange stenosis or something else going on, or is there another reason for this?
And again, this turns out also to be a positioning problem.
And when we actually did more imaging on this patient, you can reproduce this artifact by putting your cursor too close to the vessel wall.
And just so remember, in sagittal imaging, you really can't tell where the center of the vessel is.
And if somehow you get your cursor too close to the back wall or the near wall that's close to you, you can produce this.
So here is this artifact again that we have from being too close to the wall.
And when you get the doppler gate correctly positioned in the center of the vessel, you get a good upstroke and a little dichotic notch and good diastolic flow.
And normal velocities, again, remember near the edge of the vessel, the velocities are going to be lower because that's what happens.
You have some friction and drag along the edge of the vessel.
So if you see very, very low velocities and don't see an explanation for it, consider that you may have a cursor position abnormality.

Case 3: Renal Transplant Postoperative Day 1

Okay, next case.
We're now looking at a different part of the body.
This is a renal transplant and the patient is just one day postoperative.
So you can see here, the sonographer is collecting data from all parts of the transplant.
We wanna make sure that everything is perfused.
And you can see here in the lower pole, you can see an arterial waveform here.
Resistive index is a little bit low, it's a little bit under 0.5.
There's a tremendous amount of diastolic flow in this transplant, which means it's probably working like crazy to receive all the new blood it's getting from this patient who's this is, its only kidney.
And this is a kidney that's getting used to its new position in the world.
Here we are in the middle of the transplant, again, resistive index, a little bit low, 0.48 lots and lots of diastolic flow.
So my question to you is what's going on here in the lower pole?
The sonographer came out and said, I'm really worried because the resistive index is 0.39 and it's got a tardis parvis wave form.
So what is her error or is there an error here?
Is this real? And what you need to remember is that when you're looking at color flow and looking at a transplant, if you look at the arteries, when you're looking at the top part of the transplant, the arteries are gonna go from the hilum to the periphery and the arteries will be red, correct?
And so down here, when she was sampling, she's actually sampling something that looks sort of blue, but remember again, things can pulse in and out of the picture down here where she was sampling where she thought she was sampling an artery.
This is coming up towards the hilum.
And this is actually, if you look carefully, this should be a vein.
And when you look again at all these other wave forms, you can see the arteries are here.
But all this flow that's below the baseline and wrapping around, that's all aliasing from very, very, very great venous flow.
So she was getting in this picture, for example, the vein aliasing and an artery, and she actually measured the resistive index on the artery.
So the answer here is she was actually measuring a vein and the artery is this little guy here that she's got also in the image going below the baseline.
So here's just an example from the main renal artery showing, no, this is not a problem with a stenosis or or any kind of spasm.
The velocities here are normal, and the ratio to the iliac was normal as well.
And the waveform is normal here.
Good upstroke, lots and lots of flow.
And in the main renal vein, again, lots and lots of flow, very, very pulsatile in this transplant that is just getting revved up and absorbing all the blood flow from the body.

Case 4: Carotid Bruit in Male Patient

Okay, another waveform IQ question here.
Here's a male who has a brewery and we're looking at the neck.
So here is the common carotid artery and you can see this very, very bizarre waveform.
Doesn't look like any normal artery that you've seen before.
Here is the external, at least we see an upstroke here, but again, it's somewhat bizarre.
And the internal carotid artery, even though we're in the center of the vessel, also has a bizarre waveform.
So what can cause this?
Well, we have as I said, very irregular waveforms.
And if you looked at the velocities, the peak systolic velocities were also very low for for the carotid system.
And we have flow above and below the baseline throughout the cardiac cycle.
Okay, so here's a sampling actually from the edge of the vessel as well.
And you can see we have flow blue and red, which means we've got flow in both directions.
So this is an example of a carotid dissection.
And this patient actually had dissection into both common carotid arteries.
You can see it here on the CT reformat.
The waveform tends to be bizarre, irregular and very dampen, and they will vary according to the extent of the dissection and the sizes of the true and false lumen.
So it can be anything from a normal waveform to a bizarre one.

Carotid Cases: Cardiac Pulsations

Intraaortic Balloon Pump

All right, we're gonna do a few more carotid cases here, just to test what you know about cardiac pulsations.
So here's a patient with an abnormal physical exam.
I'm not telling you what's wrong with him, but you can see we're looking at the vertebral, the ICA, the CCA and the other side.
And these waveforms are abnormal everywhere you look.
So this tells you that you're dealing with a heart problem.
This has gotta be a central disease.
And so you're gonna be looking for heart problems or heart solutions if you will to this issue.
And the things you can tell about this waveform is you've got good systolic upstroke, but then you have a mid or an early systolic retraction, it comes back up again and then reversal of flow at the end of diastole.
Okay, so this diastolic flow reversal at the end of diastole turns out to be sort of the key to what's going on here because there is one particular device that can do this and that is an intraaortic balloon pump.
So this mid systolic retraction is due to the pressure drop after you've done your first pumping and then you inflate the balloon and you've got the second peak of forward flow.
So the heart does this, but it isn't a very good pulsation from the native heart.
Here's the balloon pump and then there's the flow reversal at end diastole after the balloon deflates and you've lost all your pressure and it goes backwards.

Aortic Regurgitation

Okay? 23-year-old man with chest pain and a brewery.
And how is this wave form a little bit different?
This is from Dr. Leslie's scout from Yale.
And you can see here we have an upstroke and we do have this reversal at and diastole, we don't have any of that really that mid systolic retraction.
And this is part of a natural process.
And you could look at the patient's history on the electronic medical record and see that no, there's been no pump or device put in here.
And this basically sharp upstroke, sort of a narrow peak, rapid deceleration.
And then this reversed early and and diastolic flow tells you that you have a particular abnormality with the heart.
And you can see that the velocity here are very, very high.
The heart really just pushes that blood out, but it just can't sustain the pressure and that's because you have a valve problem, which is aortic regurgitation.
So this has been called the water hammer.
Pulse can be seen with severe aortic regurgitation and again a very sharp systolic upstroke.
Sort of a narrow peak here, reversal of flow in mid and late diastole and very, very elevated peak systolic velocity.

Left Ventricular Assist Device

Alright, this patient is being worked up for heart transplant evaluation and we have a lot of these folks and they seem to like to look at their carotids to see if there's some underlying carotid disease that they're gonna need to worry about when this patient is on bypass and in the or.
So the key finding here, again, we've got an abnormal waveform and it's in all of the vessels.
The abnormality is there's no really good sharp systolic upstroke.
And the velocities are very, very, very low.
So in this case, you could be worried about a couple of things.
One is could it be cardiac myopathy?
But again, we really don't have much of a recognizable waveform here.
So there's just no flow below the baseline.
And if we looked in the femoral arteries, we would see the same findings.
And this is from a left ventricular assist device.
And basically the blood is diverted from the left ventricular apex is propelled by a pump through a graft into the aorta.
And most of these devices basically provide continuous forward flow throughout the cardiac cycle.
So this looks almost like a vein that you might see, but it's the blood flowing through all the arteries just from this continuous sort of rotary device.

Case 8: Portal Vein in GI Bleed Patient

Okay, we're gonna move out of the neck and into the abdomen.
This is a 48 year male, 8-year-old male who has a GI bleed.
And you can see here's the gallbladder and here's a little bit of liver and this is the portal venous area.
And what we notice immediately on the gray scale and some of and here also on this gray scale, partly gray scale images, that there are lots and lots of echoes in the region where there should be a portal vein.
And but in some of the areas of the portal vein, when we've got the color on, you can see that there is some flow and the flow is blue and it's reversed out of liver.
Okay? So and I've got a wave form for you in this portal vein flow.
Okay? And you can see it here flowing blue below the baseline and it's somewhat puls atal.
So I've given you an hepatic artery waveform for comparison to show you what the normal arterial waveform should look like.
So the question for you here is what's causing this kind of flow through the portal vein And as I said, we've got away from the transducer and the pad artery flow.
You can see here is aliasing and there's a normal arterial waveform again in the hepatic artery, regular pulsatile flow in the portal vein.
So is this just pulsatile portal venous flow and portal hypertension or is it something else?
And of course we're doing a quiz, so it must be something else, right?
But it's important to recognize this in day-to-day practice.
So could this be cavernous transformation of the portal vein?
Is this an hepatic artery portal vein fistula?
Is it just portal hypertension with reverse flow?
You're already thinking maybe not 'cause she wouldn't just show something that simple or is this a tumor thrombus?
So cavernous transformation, the key here is that you may or may not see some thrombus still there, you may not see it filled with vessels like this.
But the waveform here is similar to a normal portal waveform and it's very, very monotonous.
So you shouldn't be as pulsatile as our waveform hepatic artery portal vein fistula.
There you could expect a very, very pulsatile flow.
But you should see low resistance flow actually in the hepatic artery as well.
So here it would be in the portal vein, lots and lots of low resistance flow.
But in the hepatic artery, there's a lot of diastolic flow because this blood is running off into the portal system.
And here's just the angio example of this case portal hypertension with reverse flow.
Usually the luminous patent, although you could have a partial clot, certainly the flow is opposed to the pad artery, but as we said, the portal vein wave form should be normal.
And even if it's somewhat variable as this one is, you shouldn't see these regular arterialized spikes.
So of course we're di dealing with a tumor thrombus.
And the importance of making this diagnosis is that you may not see the tumor in the rest of the liver.
It may be quite infiltrative or it just may be difficult to see.
And in this case, here's the CT that goes along with it.
This is the arterial phase.
You can see the arterial phase enhancement in this portal vein.
And this patient actually was biopsied and this came back as a tumor thrombus.
So just a reminder, tumor thrombus also often has visible flow within the thrombus with doppler you don't wanna make mistake small residual flow of a non occlusive clot with a true vascularized clot, which would be in hepatic artery waveform.
So it's the waveform that tells you that this is actually a tumor.
And CT can be used certainly for correlation or to try to find the primary.
And the treatment of course is actually to biopsy the tumor because that stages the patient as well as makes the diagnosis.

Case 9: Mesenteric Ischemia Rule Out

Okay, still another case in the mesentary.
Here's a patient with weight loss diarrhea.
And the question is rule out mesenteric ischemia. Okay?
So we're gonna look at the celiac artery here and the superior mesenteric artery and at least on the color on the power doppler image here, they look pretty open here.
It is in transverse the celiac artery with its bifurcation.
And we're gonna get velocities in the aorta and the celiac, the SMA, and we're gonna look at the IMA if we can.
And so here are our waveforms and I'm just going to remind you briefly of the criteria for mesentary ischemia and then we'll see if any of these qualify.
So for the celiac, we're looking for velocity greater than 200 SMA greater than 2 75 IMA greater than 200 and ratio at least in the IMA greater than 2.5.
And maybe in the celiac and the SMA as high as three to one, we're looking at the aorta here as the denominator for our ratio.
So do any of these meet the criteria?
Well, the celiac is about one 70, but the ratio here to the aorta is about only about two to one.
Same thing for the SMA, ratio about two to one and the IMA is same thing.
Ratio is about two to one.
None of these velocities are over 200 and certainly not over 2 75.
So what could be our problem here? Where's the trick?
Okay, so do we just send the guy away as normal?
Well, there is an abnormality here and the question is what is it?
So it's not in the velocities, it's in the waveform.
And when you look at these waveforms, there's one of them that looks different from the others and that is the celiac.
You can see that there's a lot of diastolic flow here.
And so that tells me that probably that the systolic velocity is sort of maxed out here and that we may be dealing with something that's trying to increase the diastolic flow just to get blood through a narrowed area.
Just to remember that color doppler or power doppler actually is an overlay over your gray scale and you can significantly underestimate the diameter of or size of a vessel if you're just looking at your color.
So there's low resistant the celiac.
And the other thing to notice here is the IMA is quite prominent.
Often people don't have much of an IMA.
And so when it gets big, be thinking that maybe one of the other vessels might be in trouble as well.
And this was an example of a color bleed over a stenosis.
Here's our celiac. This is that transverse view I showed you.
And you can see here is the CT on this guy.
There is almost no celiac left.
It's completely encased here by a soft tissue mass.
Here's the SMA, here's the origin and the soft tissue mass is actually coming around here, but not affecting the origin of the SMA as greatly.
And here on the PET scan, you can see this is hypermetabolic.
This is hypermetabolic, and this was pancreatic cancer, which was invading the mesentery.
And the patient actually had mesentary ischemic type symptoms with the diarrhea and so forth from the pancreatic tumor.
So just a reminder again, when we're dealing with color doppler as well as the waveforms, remember to look not just at the color, but maybe also look at the gray scale around the image because I think that was our other mistake here.
This whole mass was there, but we were so busy looking at the color, finding the vessel, finding the velocity, and so happy that we saw them that we failed to notice that there was actually a soft tissue mass around this whole origin of the celiac.

Case 10: Hepatic Vessels in Transplant

Okay, hepatic vessels, we look at transplants all the time and one of the dreaded complications of transplant is hepatic artery stenosis.
And to make that diagnosis, we actually look for the resistive index and we'd like the resistive index to be above 0.5.
So the question to you is, is this hepatic artery stenosis?
And this patient certainly has a low resistive index.
It is post-op day zero.
And what can the waveform shape tell us that maybe this ratio between the peak systolic minus the end diastolic all divided by systolic can't tell us.
So I'm looking at this and I go, I know it's a low resistive index, but I'm not worried about it because the waveform shape is not tardis parvis.
This is a straight up great velocity.
And this is basically great acceleration and the velocity actually, although this is not angle corrected, is pretty good as well.
So if I see something that's not tardis parvus and has really good acceleration, even have it has a lot of diastolic flow, I don't worry because I know that this diastolic flow is actually not from a restriction that we just saw in the prior case, but again, like we saw in the renal transplant case some, but a patient who is just shunting blood like crazy through a new organ.
So this has been called intraparenchymal, shunting or reperfusion injury if you will.
And so these patients actually recalibrate and usually within a day or so become normal again.
So here is that same patient a day later.
Normal acceleration, normal resistive index in a well-functioning transplant.
So first 48 hours per post-op is when we see this.
You can see this high diastolic flow, it can occasionally have this tardis parvis wave form.
If it's a little bit slanted, that can worry you a little bit.
But again, if the velocity is high and especially this one is better in terms of angle correction here, if the velocity is high, it's usually not a stenosis and you just wait for it to get better and it does.

Case 11: Liver Transplant Low Resistive Index

Okay, here's another transplant patient liver transplant.
Another example of a patient with a low resistive index and we do look at all the different vessels.
So here is the left hepatic artery.
This is what is normal. Here is the main hepatic artery.
This one is a little bit low, a little bit below 0.5, and here is the right and this is definitely low, it's at 0.39.
And again, this looks a little bit tardis parvus.
So again, is this a stenosis?
And it can, I can tell you that stenosis can involve certainly just one vessel or they can involve even the main vessel.
But then you'd usually expect the right and left to be involved as well.
But they certainly can involve just one waveform.
So here we've got pretty good waveform shape on the left.
So maybe there really is either something just happening in the right hepatic artery or is there something else that can cause this?
And if you're looking at the images, again, don't just look at the waveforms, you wanna look at the color images and you do see a big, big vessel here.
And is that a clue?
And you also see the portal vein next to it. Okay.
And you see maybe a little bit more vasculature in here than you're used to seeing.
So that should make you think maybe I'm not dealing with a stenosis where I usually would see less vessels.
Maybe I've got some kind of am malformation going.
And so if you look around and line up your probe properly, you can see an area of aliasing in here.
And this is basically a very large arterial venous fistula.
You can see here again on the arterial phase of the ct, the arteries here and the portal vein filling early.
You can even see some little clips here where they tried to coil this thing unsuccessfully as it turns out.
And you can see the arterialized filling here of this large portal vein.
And that is also gonna be one thing that drops your flow.
Okay, so this is a common complication.
Most of these are asymptomatic and we see them often after biopsy in up to half of the patients, but most of them close spontaneously and less than 10% will persist beyond a week.

Case 12: Liver Transplant Portal Vein Issue

Okay, one more transplant question for you here.
What do you do with this case?
So the patient comes in and you can see the main portal vein.
We have really very poor flow and we just don't see it very well.
The sonographer has said main portal vein area, she's sampling all around and all you see is an hepatic artery wave form.
This patient is just a few days post-transplant and in this patient the left portal vein is reversed and so is the right.
So we have reverse flow in both of the portal veins inside the liver and we can't see the main portal vein.
And there's really no reason for this patient to have portal hypertension.
It's a brand new liver.
So the question is why can't you see the main portal vein?
What's wrong with this? And in this case you really need to know to get a CT because you haven't been able to make the diagnosis.
And in the answer in this patient it was there was very sick, very large hematoma that's compressing this portal vein.
This is the portal vein on the ct.
You can see it's narrowed down to a slit.
And so the patient did go back to the operating room, this was evacuated.
Here is the portal vein down here at the confluence with the splenic vein where it's normal in caliber.
And so after decompression, lo and behold the portal vein reappears and now that there's no obstruction to the flow, actually there's good forward flow into the into the liver as you'd expect.
And you can see post decompression ct, it returned to normal as well.

Case 13: Liver Transplant Poor Function

Okay, there's one other thing which is sort of an unusual problem for liver transplants.
This one has poor function and also has some bizarre waveforms.
So here is the left hepatic artery and you can see that there's just no flow in diastole.
So it's got a very high resistance pattern, which is very unusual considering that the right hepatic artery is tardis parvus and the main hepatic artery is tardis par.
So just these waveforms alone, these very low tardis parvis waveforms in a liver transplant with poor function would make you think about either hepatic artery stenosis or thrombosis.
This one is just again, maybe will jog you because this waveform is just so unusual and it doesn't make sense to me at least.
You can see the right portal vein, there's plenty of flow in to the liver and it's somewhat pulsatile and it's very easy to see the portal venous system.
Okay, this is an example here.
This patient needs to go to angio to see if there's a problem.
And you can see when we squirt the angio here is the hepatic artery.
There's no stenosis, but there's very little contrast in it.
And with contrast is mostly going tear to the left, which turns out to be going to the spleen.
And this is a phenomenon actually known as splenic artery steel.
So this patient, you coil the splenic artery and basically embolize the spleen because the spleen is shunting this blood away from the liver.
And once you get rid of the spleen, it doesn't get better right away.
So here's the r hepatic artery.
It even looks a little worse I think than it did pre-op, but the main hepatic artery is getting better already.
It's down, you know, the resistive index is rising, there's much less diastolic flow.
And within 24 hours the r hepatic artery was also improving and getting, again, a much better upstroke.
So that means that the the ischemia that you were seeing, that tardis parvis wave form has been relieved and now the liver is much better perfused than when the spleen was stealing its blood.
So we don't really know what causes this.
Some people think it's a consequence of excess portal vein flow.
Basically it's an arterio graphic diagnosis.
So your job on ultrasound is to see those abnormal waveforms.
One of the things that's been reported in the literature is an elevated resistive index with no diastolic flow.
Or and all these waveforms will also be low velocity as well.
If you can get an angle corrected velocity on them, which is hard 'cause they're really, really small.
Again, angio will demonstrate increased flow to the splenic artery or sometimes to the gastroduodenal artery.
And the therapy will be basically to embolize the artery that's stealing the blood away.

Case 14: Renal Transplant Day Zero

Okay, let's move down back into the pelvis.
This is a renal transplant again and this is day zero.
And we do a one day or basically an early post-op image of all our renal transplants to see that they're perfused.
And when we found this one, you could see again, this is very abnormal flow.
So here is flow, it's going into the into the kidney, but it looks almost like it's venous, doesn't it?
It is very, very tardis parvis almost like it's at the capillary level.
And when we looked at the main renal artery in the hilum, this is what the kind of flow you'd like to see out in the parenchyma.
And so again, low velocity flow, lots and lots of diastolic flow.
So the question becomes, what's wrong with this?
Is there a stenosis? Is there a kink?
So you need to trace out the rest of the vessel.
And when we did, we found an area in the renal artery that had a velocity of almost 330, which is sort of high, and compared to the iliac artery which was at a hundred.
So there's a three to one ratio here.
And I actually like the ratios better than I like an absolute velocity because you can have lots of flow through these transplants.
And if the iliac artery is pounding along at 250 centimeters per second and then the renal artery at the anastomosis is at 300, that's not much of a ratio or a cutoff.
So I wanna see a couple things happening, I wanna see a ratio and then I also wanna see what's going on downstream.
So obviously downstream this transplant is not well perfused.
It's got tardis parvis and there is a big ratio.
So what could be causing this?
'cause boy, this artery looks just great on the power.
So this basically requires the patient gets re-explored as well because you could have something pressing on this artery rather than an intrinsic stenosis.
It could be pressing on it or you could have some kind of a dissection or something in it that happened at the time of surgery that's giving you this elevated velocity and then giving you the tardis parvis downstream.
So this patient did go back to the or and basically this was an arterial compression syndrome.
They repositioned the transplant got the kink out of the artery and they revised it.
And you can see that the waveforms now are normal out in the parenchyma as well as the waveforms are now normal in terms of the resistance here in the main renal artery.

Case 15: Renal Transplant Day One

So our next case is sort of similar here is a patient again, day one post-transplant and instead of the tardis parvis waveform, the waveform that we see actually here is diastolic flow reversal.
So we've all been taught to recognize this and say, well we think that this might be a renal vein thrombosis.
And sure enough, when we look for the main renal vein, the sonographer has said main renal vein area and you can see sort of a soft tissue component here.
But again, no main renal vein exiting in the hilum where you'd like to see it.
And we don't see many renal veins here in the parenchyma as well.
So the patient again, returns to the operating room and you would expect to either evacuate a renal vein if there was a renal vein thrombosis.
But in this case, again, the transplant was repositioned.
And this is another example of a compartment syndrome.
This is a patient who has renal vein compression and you can see again after repositioning the waveform does return to normal.
And you easily see the main renal vein here being displayed below the baseline.
So this is thought to be related to ischemic injury and swelling from reperfusion.
As you put the allograft into its new host.
The doppler findings can mimic those of renal vein thrombosis with this re reverse diastolic flow and surgical pressure relief actually is what you need to preserve the function of the transplant.
And here is another example again, after decompression the transplant looks like normal.

Case 16: Late Renal Transplant Assessment

Just one more renal case for you.
Here is a patient who has been out for a while, but the transplant's not performing very well.
So they come in to assess for renal artery stenosis and as I already mentioned, we look for elevated velocities but we also look for tardis parvis waveforms downstream effect.
So here's an example of a tardis par waveform in the parenchymal arteries here.
And so this this transplant is at basically has some ischemic findings as well at the anastomosis.
We can see the veloc is 2 27.
In a renal transplant up to 200 is certainly normal.
Above that I start looking at the ratio of the iliac.
Again, I want at least a two to one ratio, but preferably even higher, more like three to one before I call stenosis.
So the veloc is a little bit high but again, the arterial waveform, there's a lot of sort of diastolic flow here and it's not particularly that abnormal.
And then when we look at the iliac artery, the velocity here is one 90.
So there's definitely no step off in velocity between the renal artery and the iliac.
And the waveform in the iliac looks like it does in the renal.
Now that's very abnormal because the iliac artery should have a nice brisk upstroke and it should have some reversed flow in early diastole and then come back above the ba the wave, the baseline.
So that tells you that the problem basically is not at the level of the anastomosis.
It's actually before that because we don't have our step off of velocity here.
And we have a waveform abnormality that precedes this abnormality in the renal artery.
So we have tardis parvis waveforms and normal ratio.
And so we wanna look up at the iliac artery up higher if we cannot see it by ultrasound, you can certainly see it by ct.
And this patient, you can see this white is all, that's all calcium.
So this is the artery here and there's certainly at least a 75% diameter reduction of this iliac artery.
And the transplant is actually hooked on below this area of narrowing.
So this patient needs their iliac artery fixed and that will improve the inflow to the transplant iliac artery stenosis.

Venous Cases

Monophasic Waveform in Common Femoral Vein

Let's move on to some veins.
And this is the right common femoral vein and here is the patient in left lateral decubitus.
So your diagnosis here, you have a monophasic waveform.
This is a more normal waveform and we've repositioned the patient.
So what is the patient's problem?
Is there an iliac thrombus above this?
No, this patient is pregnant and there's uterine compression extrinsic on this vein.
So if you've got your pregnant patients with swollen legs, rule out DVT and your waveforms look like this, this is a really nice trick to turn them, get that uterus off of the vena cava, get it off of the iliac veins and you may be able to return the normal pulsatility.
So monophasic waveforms are abnormal.
Here's just an example in this patient.
It's not always a very large difference, but if there's an asymmetry, they you should look for this waveform to go at least halfway back towards the baseline.
On the left side here it does, although not very much the right side, it doesn't.
And this patient this is an indirect sign of proximal obstruction.
You can see here is a large adenopathy all around the aorta in this patient who has metastatic cancer.
We actually looked at this we did a five year retrospective review of almost 3000 patients.
We found about 124 that had monophasic waveforms and about a hundred with correlation.
And in these patients, although about between a third and 40% had d vts up higher, a fair number of patients had other problems.
So let me just show you what some of these look like.
So I said 40% will have an iliac DVT.
So once you see this monophasic waveform, you are required to go up and find out what's causing it.
And so that means imaging the iliacs.
And if you can do it by ultrasound, you should.
If you can't then you need to go on to CT or mr.
But you can see here is a nice clot in this right iliac causing this monophasic waveform.
Here is a patient who had one week of leg swelling, came in, rule out DVT again, here's the left side for comparison, abnormal on the right.
And when you looked up higher, you can see the extrinsic compression of this vein by a very, very large soft tissue mass.
Again, this patient had a lymphoma that was diagnosed on her DVT study, got her to her CT and eventually to her PET scan.

Pulsatile Venous Waveform

Here's the opposite of the monophasic waveform.
Here is the waveform.
You can see it should be going towards the head.
So it should be mostly below the baseline.
This is very pulsatile and about half of the time it's actually above the baseline.
So that means that the blood in this venous system is sloshing back away from the heart and towards the feet far more than it should be.
And so when you do a val Salva, can you affect any change in this?
And the answer is you can't, you can't really stop the flow.
This elevated right-sided heart pressure is being transmitted all the way back along the veins.
And that's what you're picking up.
So very, very pulsatile waveforms, a large extent above the baseline be thinking about congestive heart failure.
And again, sometimes you're the person who makes the diagnosis 'cause the patient comes in with leg swelling.

Case 19: Right Testicular Pain

This is one of our last cases.
I think this is a patient who has right testicular pain.
And as you know, with scrotal ultrasound, we do a couple things.
We're looking at the color image but we're also looking at the spectral tracing.
And you can see here on the right it looks quite different from the left.
I'm gonna show you some images that were obtained during the exam.
And these are 20 minutes later.
And these are, here's now the right and the left.
And this is the right testis 20 minutes later.
So the way form looks exactly like the left.
So we had decreased profusion on the right early on and sort of a delayed upstroke.
But then 20 minutes later it was normal and the profusion looks normal.
So the question to you is, was this epididymitis with decreased profusion that we just happened to pick up in one area of the testis?
Maybe this was in a different place that we found this.
Is this partial testicular torsion and detour happening under our eyes during the exam?
Is this just technical variability?
Did the sonographer just get the waveforms in different places and they can just look this funny and different throughout the exam?
Or did I didn't give you the history, it just said there was some pain, was there some trauma and is that affecting the waveform in the testis?
So let's just answer those.
Well, for first of all, an epididimitis.
If the vascular is decreased, usually the spectral waveform becomes increased because there's a lot of pressure in the testis being exerted by the capsule.
As this testis gets emus with oras, the waveform actually often will reverse.
And you should see some hyperemia here in the epidermis here.
We can see it in the tail as compared to the testis.
Our optimal scrotal doppler technique is this side by side.
So if you have no flow, it's easy to say that there is torsion.
If there's diminished flow, you can suspect partial torsion, but you have to be very careful again that you're looking at sort of similar parts of the testis.
So you can see relative perfusion at the same level.
If you do it well, if you have trauma, you may wanna use color or even some waveforms to look for perfusion.
And in this case you see a traumatized testis.
You might see some increased flow in some areas and maybe would see some decreased decreased velocities and some increased diastolic flow.
And notice here you can see an area of hypoperfusion which is an area of contusion.
But again, these things don't come and go during the exam.
We should see them from beginning to end.
So partial testicular torsion is a really important thing to recognize.
It's a cord twist that does not completely occlude the blood flow.
Patients can spontaneously detours.
You can have a couple different patterns.
I've shown you one of them.
You can have a tardis parvus as we see here, or you can have a high resistance pattern as we see here.
So again, the cord twist obstructs the venous side first.
So the artery may look at this like this high resistance pattern.
If you just have sort of a partial twist and you've got ischemia going on in the testis, this tus parvis pattern is actually even more alarming.
Okay, so here's another patient who had some increased flow.
And this patient actually had detours just before the exam.
So after the patient detours, it can be confusing because you can see some hyperemia.
So here's our patient on the initial exam, decreased perfusion, tardis parvus waveform and diminished amplitude compared to the normal side.
During the exam here we can see increased flow and normalized or more normalized waveform.
And the answer here is partial testicular torsion and detorsion during the examination.

Conclusion

So in conclusion, I just wanna emphasize the waveform shape and velocity both contribute to diagnoses and it's important to use the right technique to ensure the proper waveform.
Be sure you're centered in your vessel and that you're sampling the vessel that you think you should be.
Waveforms will reflect local disease, local stenosis, for example, as well as proximal or distal or even systemic abnormalities.
So sometimes you need to look in more than one vessel to make your diagnosis.
And lastly, waveform expertise makes you a Doppler star.
So I hope you all use it in your practice.
And with that, thank you very much for your time.