Refining Your Lymphangiography Technique: An In-Depth Guide

[Dr. Chris Beck]
You mentioned SCDs. Were there any other big unlocks? I don't know if you can take yourself back to a stage of the procedure or just doing diagnostic lymphangiography, things that you've learned along the way that have streamlined your process or your equipment, or how everyone Is ready to go as far as making it an efficient procedure.

[Dr. Bill Majdalany]
Absolutely. What I've started doing as I've changed jobs over the years is I always meet with my team in IR, and I go over it. I show them what the setup is. I just bring in olive oil or something, and do it with olive oil just to show them what it looks like, what to expect, and to make sure that everybody knows where all these different things are in the department because, oh, how often do we use 9-centimeter long, 25-gauge needles? Or if you only use 27-gauge, whatever gauge, it doesn't matter. The other things that I've really done is figuring out your inventory to your point, making sure that things are all compatible.

At different times, there's always been backordering of one thing or another. Most recently, it seems like some of the 1cc medallions have been out of stock, for instance. I always have a backup plan where we use a 3cc or whatever. As I've got along, I've realized a few areas where people tend to mess up. One is when we load the dye in the syringes, if you're a little bit sloppy in how you do it, some of the dye can spill around the hub. Over time it erodes the hub, and it may break it. If you're using polycarbonates, and you draw it up using either a longer needle or something and make sure that it doesn't overflow, and you do a connection that isn't necessarily wet to wet, and then purge all the air out, those things will actually allow you to use it for many, many, many hours without an issue.

Then I just take dye all the way through my three-way, my 1cc and my 10cc setup and across the tubing down to my needle. The 25-gauge 9-centimeter needles have an inner stylet similar to a Chiba style. I take that inner stylet out, and I connect it so that if you put the needle into the lymph node, you don't have to twist the tubing to the hub after you've already accessed it. It's ready to go. Then I give that patient just a little wheel with a 25-gauge needle, of lidocaine. Then I go through that. I start maybe 3 to 5 centimeters away from the lymph node, and I try to angle in the actual lay of the lymph node itself so that the needle is going across it.

Then I check in an orthogonal plane to make sure I'm not off to one side or the other too much. I do a small little injection, 0.1cc, and I'll watch it with fluoroscopy. Even that 0.1cc, it should start to move through the lymphatics. As little as 0.5 cc, it's going to actually go from one lymph node to another. Really doesn't take that much. You want to make sure you're getting a nice transmission through your lymph node, A, that you're not getting too much spillage outside. I know a little spillage isn't a big deal, but then B, you start to understand how much pressure it takes.

It really doesn't take much in that 1cc syringe to get some of that lymphatic dye to go from your access point to the next nodal stations. It's just starting small and low, checking with fluoroscopy. If you're having trouble seeing it, take a spot radiograph. the amount of visualization of 0.1cc of dye, it's not that much dye. I just make sure that things are well there. Then I Tegaderm my needle down. If I need to put 4x4s under it to keep it in that same plane, I do that, Tegaderm it down, and then just keep that slow injection.

[Dr. Chris Beck]
What is the location of the lymph node that you're aiming for exactly, for somebody who's never done this?

[Dr. Bill Majdalany]
What I typically do is I'll take a look along the greater saphenous vein and the saphenofemoral junction. There's usually quite a few right around there. Obviously, I want to access a lymph node below the level where there may be any issue.

[Dr. Chris Beck]
Of course.

[Dr. Bill Majdalany]
In a typical lymphangiogram, to get a nice pelvic lymphangiogram, right around the GSV is your money ball.

[Dr. Chris Beck]
The actual specific part of the lymph node where the needle is supposed to hit also?

[Dr. Bill Majdalany]
Fair. That's a very good question because I think a lot of people focus on, oh, I want to get a perfect loop in the center, in the cortex, the high limb, et cetera." I really just try to go across three-fourths of the lymph node. I really tried to do it in the long axis. That's why I then check in an orthogonal plane to make sure I'm not off one way to the other. That way that if you have any backflow along your needle, hopefully, it is exiting through other efferent lymphatic channels before it spills out into the tissue around the lymph node. I will say this, not necessarily the largest lymph nodes are not your friends.

[Dr. Chris Beck]
Really? Okay.

[Dr. Bill Majdalany]
They may be a big target,-

[Dr. Chris Beck]
Sure.

[Dr. Bill Majdalany]
-but there may be something pathologic about that lymph node that may not be transmitting as effectively as sometimes smaller lymph nodes. The other thing I'll say is that the ultrasonographic appearance of lymph nodes may change based on age, underlying disease processes, or potential treatments that they're on. Sometimes you have to get used to, oh, it's the hypoechoic appearance, or is it just one that's rounded and hyperechoic, et cetera? I think it really pays to just do a good-quality ultrasound of the vicinity in and around the saphenofemoral junction.

You need to go above, around CFV, and or below, and take a look at what's going on to understand what's going on in that disease process. To that end, it's very common for me to take a look at a patient's prior imaging. Everybody almost has a CT that's been through some type of surgery, right?

[Dr. Chris Beck]
Sure. Right.

[Dr. Bill Majdalany]
Often, a typical abdomen pelvis CT goes all the way down to the top third of the thigh. You've already imaged that whole area you want to see. You can get an idea what the lymph nodes look like, where the surgical clips may be, et cetera, and make sure that there's no AAA, or if there is, you know what's going on, if there's an aneurysm or horseshoe kidney and things like that, that you wouldn't be able to see fluoroscopically necessarily. Those are the things that I'm really looking for in terms of the abdomen and the pelvis. In and of itself, just taking a look at what you would expect the lymph node pattern to be and where the stations are, really gives you that heads-up before you go and do that ultrasound.

[Dr. Chris Beck]
Fair. All things being equal, say, you're thinking something around the thoracic duct for a level of injury or something in the chest, does right or left particularly matter to you or just whatever side you're more comfortable on?

[Dr. Bill Majdalany]
I will start on the side of the table that we use for most-- Most tables are set up for right groin access. By default, I just start there. What I do is once I have that access, I just put my injection apparatus down, I go and access the other side. What I do is I add additional tubing on the other side. Then I come back to the right side and I inject both sides simultaneously.

[Dr. Chris Beck]
Oh, nice.

[Dr. Bill Majdalany]
We play a little bit of a race to see which side moves up faster. You'll be surprised for whatever reason, one side may move up faster than the other. There is a relationship between the lymphatics, and veins, and venous drainage. Sometimes you'll see some degree of shunting from one side, whether they've had a prior surgery, prior DVT, some type of other pathology, to the lymphatics necessarily drain back to the venous system, whether it's at the thoracic duct terminus or at stations along the way. If one side isn't giving you the feeling that you want, that's why I always do both sides to increase the chance of getting that filling in the retroperitoneum, which is where the money is, at least from a thoracic duct standpoint.

I'll do both sides very often. Generally, most of my lymphangiograms only require between 10 and 12 ccs of dye before I've already seen the cisterna chyli, and I'm ready to do an advanced intervention at that point if needed.

[Dr. Chris Beck]
As far as accessing the cisterna chyli, any tips for that? Like, one, seeing it, recognizing it, and then accessing it in a way that sets you up for success if you're going to have an intervention that you're planning for.

[Dr. Bill Majdalany]
Yes, that's a very important question. Loaded. What I do is I follow that most opaque portion of my lymphangiogram with spot radiographs because almost necessarily, with fluoroscopy only, you're not seeing the leading edge of what's happening. It's likely the lymphatic dye has actually moved further up than you think it has on fluoroscopy alone. I'm always looking higher up than where the opacity is on fluoroscopy, and I'm taking a spot radiograph. Frequently, what happens is you'll see the dye shoot up through the thoracic duct fairly quickly.

It's really only when it is accumulating, that droplets appearance, that you start to re-see it on fluoroscopy. What I do is I really start taking a look. I take spot radiographs at the very beginning of the whole patient, chest, abdomen, pelvis. Then I'll take up MAG-ed spot radiographs somewhere between L4 and T8, just to see, hey, do they have any hardware or anything funny? What are the things that may impact my visibility of the lymphatics? Then once I have that opacification of those retroperitoneal lymphatics, I move up to that same MAG again, and I'm really paying attention to the flow dynamics.

It's not that I just want to see a big target there because that big target could be a lymph node, I want to see a target, and I want to see transmission from the target, not going to another lymph node because then I can access it and potentially pass a wire through it. As I've gone along, I've moved more to almost exclusively using a 21-gauge Chiba-type needle, not a trocar tip needle because the trocar tip has this diamond that extends a few millimeters beyond the actual needle itself. You think you're in, and you take the inner stylet out, well, that's actually a few millimeters ahead of where the rest of your needle is.

Whereas a Chiba, the inner stylet is flush with the tip. You take out the inner stylet, and your needle is actually still where it was when the inner stylet was there. I put a very gentle bend, maybe 10 to 15-degree bend on the Chiba. I approach with a bit of the angulation pointed towards the head. Maybe a 10 to 15-degree angle that way, or you can angle your II to help guide it. I try to make it as straight a pass as possible because with some degree of respiratory motion, enteral loops, distending, et cetera, with gas and things like that, it can really change the trajectory.

What you really want is a nice straight thing so you don't have unnecessary or redundant loops in your course from the skin to the lymphatics. Then I probe usually with a V-18 wire, and you really want to see it shoot up and straight. Every once in a while, it may be in the aorta or in the IVC. That happens. It's completely expected, generally very safe with a 21-gauge needle. Our forefathers in IR used to trocar aortas with a-

[Dr. Chris Beck]
That's right.

[Dr. Bill Majdalany]
-6 French needle catheters and things like that, and just pull out.

[Dr. Chris Beck]
Sure, the cost of doing business back then.

[Dr. Bill Majdalany]
We freak out about hitting it with a 21-gauge. It'll be okay.

[Dr. Chris Beck]
Sou're approaching a target. Once you think you're in, are you doing anything to confirm in the lateral projection, or–

[Dr. Bill Majdalany]
I think that's a great point. Sometimes I'll use the lateral projection if there isn't enough dye filling. If the dye is already filled, the thoracic duct and the wire is clearly intraluminal and moving with that type of intraluminal feel you expect it to have, as opposed to having some resistance or feeling weird in the retroperitoneal fat or when you're not really in a vein, et cetera, then I don't tend to go lateral. I always encourage it, particularly as you get more experience with the feel.

[Dr. Chris Beck]
Once you have wire access, your wire shoots up, you feel like you have whatever working wire you have, I think you mentioned V-18, what's your next line as far as having stable access, bareback, versus if you're planning, and we're assuming now that you're planning something like an advanced intervention like an embo?

[Dr. Bill Majdalany]
My go-to catheter ends up being a 2.4 Progreat. You can get a wide variety of sizes of coils and anything else to flow through a Progreat pretty easily. If you want to do better-quality diagnostic imaging, it's obviously easier to inject through a 2.8 Progreat rather than a 2.4. The reason I like the Progreats is they have a little stiffness to them. They're a little bit more reinforced than some of the other catheters, like an STC, for instance. I feel like you have that ability, and they tend to track pretty well. I think a lot of Terumo products are known for the trackability, for instance.

I feel like that tracks pretty easily over the V-18. On occasion, if I've ever had trouble getting it in, maybe my angle is a little bit weird or it's not perfectly straight. What I do if I have a V-18 in is I take the inner metal and the inner dilator of a MAK-NV kit or an AccuStick that are about 3 French. I use that metal to support and get that other catheter in to help straighten out the tract, and then I can come back. At that point, because I've done that, I'll probably go in with a 2.8. If I ever want to change from a 2.4 to a 2.8, that's what I also do.

You can get the metal down pretty close to it. Then usually, the outer dilator with the 3 French will cross over. A couple of occasions where it's been a little bit challenging, I'll use a Navicross with a Progreat inside of it just to support to getting down there. In general, the bigger your access in there, the higher the risk that you're going to have gone through something that may cause you a problem at the end. In general, you want to keep it below 4 French.

[Dr. Chris Beck]
Say a Backtable listener is now feeling very inspired by this episode and they want more-- We actually do have some good episodes on this, and we'll link to them in the show notes. Other than having to learn this over multiple years with multiple sources, do you have any good resources that you can point people, either like, "Hey, this is just where you start, this is the ABCs of lymphangiography," or, "This is a good understanding of the lymph system," whether it's papers, lectures that you've listened to, or even given?

[Dr. Bill Majdalany]
Absolutely. At the risk of sounding like I'm plugging myself,-

[Dr. Chris Beck]
No, plug away, dude.

[Dr. Bill Majdalany]
-there was an issue of seminars of interventional radiology maybe in 2020 or 2021. I was a guest editor, but the whole issue was dedicated to lymphatic imaging and intervention. It's 12 different articles written by 9 different authors. You have a good lay of the land from all around. It's broken down to lymphatic anatomy and physiology, and then based on traumatic chylothorax, how to approach that with algorithms, non-traumatic chylothorax, chylous ascites, and lymphoceles, hepatic lymphangiography, et cetera. It really covers a lot. Prior to that, one of the gurus, Max Itkin, had a similar thing in techniques. That was a few years before maybe 2016, 2017, but those two things really have a lot of the information, including the setups of how to do it, et cetera.

[Dr. Chris Beck]
We'll actually link to both of those references, seminars and techniques whenever they cover an entire topic on something. That can actually be just pure gold. Those are fantastic. You were the editor for it. Who were some of the other contributing authors?

[Dr. Bill Majdalany]
Max Itkin and Greg Nadolski, the group out of Memorial Sloan Kettering with Ernesto Santos, Wally, Waleska Pabon-Ramos from Duke. I actually had invited-- One of the articles was from plastic surgery on the management of lymphoedema. I think it's really important to hear the perspective of our plastics colleagues. What could they do for us? What can they do for these patients? Because almost always, we'll see somebody with leg swelling, and we're like, "I don't know what to do for this patient." Debbie Rabinowitz discussing pediatrics, Matt Hawkins in Indigo discussing lymphatic malformations, et cetera, et cetera. A good cross-section across the country, domestic and international. Claus Pieper from Germany, talking about different techniques for MR lymphangiography as well. He's a guru in that.

[Dr. Chris Beck]
Very cool. Is there anything that I didn't ask about-- Actually, how about this? If you just had to sum it up and say, you've been at four different institutions, what has been the top three takeaways or success points for you as far as being able to build this practice at each place that you go to?

[Dr. Bill Majdalany]
I think number one is just giving it a try. Like I said, almost any IR practice at some point has to do a para, a thora, a chest tube, something more than other clinical services are able to do, or maybe needs imaging, depending on your local practice pattern. Understanding how to work it up, and then coming back and adding value to that, to the care of the patient, I think gets you a lot of respect from the other people who are taking care of patients. It's easy to shy away and be like, "Okay, hey, I stuck the needle in, and I'm walking out. Hey, you guys just pull it when the patient is done and send them up."

You sit there and you see the fluid, and you say, "Oh, hey, take that next step, and say, I'm going to send it for fluid testing based on what I see." If it's a chylous, I want to send it for triglycerides. What if it's non-chylous? One of the things that I've really learned and really talked to people a lot about is how do you work up lymphoceles? There's always this misconception that people want to send it for triglycerides, but that's actually not what you should be sending it for. What you should be sending it for is a cell count because the triglycerides don't filter into the lymphatic system at the level of the groin.

They filter in from the mesentery and that comes in at the cisterna chyli. It's a much higher area. I've seen this in partners at different institutions. They say, "Oh, I sent it for triglycerides. There's no triglycerides, it's not a lymphatic leak." Actually, triglycerides tell you that it's a chylous leak. They tell you that it's a lymphatic leak. What you really want to send it for is a cell count, and what you see is a preponderance of lymphoceles. Typically, greater than 70%, 80&, 90% of the cell count will be lymphoceles. That's what I always tell people is that, it has that appearance. It looks like urine.

The triglycerides will be low. You'd send it for a urine creatinine to work it up. The creatinine is low, but the lymphocyte count is out of the roof. That's how you then know that it's going to be a lymphocele. You do a lymphangiogram. Now you've done a tremendous service for the patient. You've fixed their problem with a 25-gauge needle, that otherwise would be marsupialization or something else. I think there's always this misconception of it's a lymphatic leak. We're going to do dietary modification. The dietary modification doesn't fix a groin leak. The small bowel doesn't circulate in that way.

[Dr. Chris Beck]
It's the back pressure.

[Dr. Bill Majdalany]
Yes, exactly. What I always tell people is that there is an understanding of lymphatic anatomy physiology. It's a very distinct circulatory system. It's very different from how arteries and veins work because it has three different and separate components, which don't communicate until they get to the cisterna chyli. Each component is unique. The mesenteric component is going to be lipid-rich. The hepatic component is going to be protein-rich. The peripheral component is going to be electrolyte and lymphocyte-rich. Knowing how to test for a leak in each component is the most important thing.

[Dr. Chris Beck]
That's a good tip. Why is it that IRs shy away from this? Do you think it's under-recognition? Under appreciation? We're scared of it? Under training? Under education? Combination of all these factors?

[Dr. Bill Majdalany]
The typical medical student gets very little teaching about lymphatics. Hours, or oh, you hear about lymph nodes and metastasis. In and of itself, the actual understanding of the lymphatic anatomy and physiology is not something I was ever taught in medical school. Certainly, even through radiology residency, had I not gone through the residency that I'd gone through, I would not have been exposed to it. I can say that a large majority of people, as recently as 10 years ago, did not have education in this. At least even in the IR spectrum.

Now it's routinely at many meetings. We discuss lymphatics and things like that. I think that's part of it. I think the other part of it is that there are so many things to do. There is this perspective, misconception potentially, of, oh, I don't want to have to get all of this inventory, or, oh, it takes a long time, or et cetera, et cetera, et cetera. It's just one more thing to learn. To me, it takes a routine procedure and you problem-solve and add a big benefit. Most importantly, I look at it from a building practice standpoint. It was not lost on me as a resident.

We worked with a thoracic surgeon so closely. A lot of academic places were not doing arterial stenting or even the IVC filters. Oh, who does the IVC filter at your hospital? This, that, the other. It's funny, when you think about it. It was not lost on me that the thoracic surgeons relied on us for everything when it came to their patients. Whether it was, if they had a DVT, we would do the thrombectomy, the IVC filter, the enteral intervention. The arterial intervention, if they were doing a gastric pull-up and they needed a celiac stent. The thoracic duct embolization surgeon said it was a way that practice and relationships were built.

When you can solve a problem for somebody else, they're going to go to you because they trust you, when you can solve their hard problems, to solve their simpler problems that a lot of other people could trust. Particularly when you have that face-to-face interaction, they know that you care about their patients. They know that you help them achieve excellent outcomes. To me, that is a cornerstone of lymphangiography and lymphatic interventions is you're solving somebody else's problem for them. They're going to reciprocate, and they're going to want to come to you to solve their easier problems when you can help them with their hard problems.

[Dr. Chris Beck]
I don't know about the rest of the audience, but if that doesn't get you excited about getting into this and knocking down some of the roadblocks and charging full steam ahead at lymphangiography, I don't know what it is. Good plug, I like that. Thanks, Bill. Anything that I didn't ask you, Bill, that we should have talked about? Don't get me wrong. I still think Backtable, we're still scratching the surface of this, and we're going to have a lot more episodes to do on it, but anything else left unsaid that you'd like to plug or talk about?

[Dr. Bill Majdalany]
As I say, the last thing that I'll say in regards to lymphatics is that this space has dramatically evolved in the last 10 years. We went from thoracic duct embolization, now we talk about hepatic lymphatic embolization, thoracic duct stenting, thoracic duct recanalization, trying to understand the pressures, using the thoracic duct as a way to decrease portal pressure in patients with ascites and variceal bleeding and understanding new diagnoses of this protein-losing enteropathy, protein alveolar proteinosis, plastic bronchitis, et cetera.

It's not just the iatrogenic leaks. It's all these other things that gets back to the lymphatics are interrelated through every organ and every circulation throughout the body. This is going to continue to evolve. At some point, I predict that we will have trans-lymphatic interventions for oncology. I do think that we will continue to understand the space of endocrine and how the lymphatics serve as a reservoir for hormones and understanding fluid balance in the body, and heart failure, and ascites, and how the lymphatics have an interplay with that, and the pressures. I think these are all things that are going to continue to happen.

[Dr. Chris Beck]
In your estimation, this is my takeaway of this, one, in our understanding of the lymphatic system, I don't know if we're at elementary school level, but maybe junior high. It's only going to continue to evolve if you're a young interventional radiologist looking to cut their teeth, or publish, or just develop a practice. This seems like green pastures, in my opinion.

[Dr. Bill Majdalany]
Absolutely. I'd say green pastures, blue water, I think there's a lot to do. I see, the group out of France did, [in their] JVIR article, measuring pressures in the thoracic duct pre-imposed stenting for patients with ascites who couldn't get transplants and were non-TIPS candidates, et cetera. How we could still help a third of them who are medically refractory resolve their ascites. This is dramatic. That is a new paradigm. Say, okay, I can't give somebody a TIPS. We all see this, oh, maybe their MELD is elevated or whatever. Understanding which patients to treat, which ones are going to have better outcomes than other is to me that next cool thing. How we can use that to change the course of patients who others would say, "Oh, hey, they have really terrible liver function." No one even thinks about intervening through the lymphatics, but it's there.