Ultrasound Guided Head and Neck Procedures - HD

Introduction

Hi, my name is Dr. Daniel Swerdlow.
I am associate professor of Radiology at Georgetown University Hospital.
And today we're gonna be talking about ultrasound guided procedures in the head and neck.

Okay, I have no financial disclosures.

Objectives

Here are the objectives for today.
We'll talk a bit about indications for biopsy.
We'll talk about the techniques that we'll circle back around to this repeatedly.
I'll talk about when you might want to do a fine needle aspiration versus a core biopsy,
and then I'll talk about a few more advanced things.
When things get a little bit more difficult, what are some of the tricks I do to overcome the problems?
And briefly, we'll review the few complications that occur.

Common Biopsy Sites

More or less, in order of popularity, these are the biopsies we do.
Thyroid masses are far and away the most common, followed by lymph nodes.
Everything else is less common.
Salivary gland masses, nerve sheath tumors, miscellaneous.
I would also include occasional parathyroid biopsies, fluid collections,
and something I've been doing more lately, salivary gland Botox injections.

Coagulation Parameters

A quick word about coagulation parameters.
I really don't make too big a deal about it, especially for fine needle aspiration.
I use very small needles.
Because they're elective, I tend to hold the Coumadin.
But if it's really a big deal to stop the Coumadin or any other major blood thinner,
I don't really worry about it that much.
And for the minor blood thinners like aspirin, I just simply don't worry about them.
If I'm going to do cores again, because these are elective,
I prefer to have these minimal standard parameters.
This is our departmental policy.
I'll make an exception in an important case, but in general, that's what we do.
And the main thing I believe is that wherever you are, everybody's sort of adhered to the same standards.
Otherwise, the clinical doctors will play one doctor off against another and it makes life more difficult.

Biopsy Techniques

Just on biopsy techniques, first off, the ultrasound 101, the most basic principles:
always use the highest frequency transducer you can get away with,
the smallest field of view, appropriate focus, compound imaging,
which is now a default on most modern machines, is very helpful.
It not only makes a lesion more conspicuous, it also makes your needle more conspicuous.
Sometimes harmonics will help, sometimes it hurts.
When I'm scanning around at the beginning, I try and turn it on, see if it makes it better.
If it does, I'll keep it, otherwise you can turn it back off because most things are very superficial in the head and neck.

I use the freehand technique with the needle in the scan plane as opposed to perpendicular to it.
I like to see the needle across its whole length.
Every once in a while, I'll use a needle guide for a more difficult thing.
I do tend to give people local anesthetic with lidocaine, although you don't really have to for a fine needle,
the needle size is about the same as the lidocaine needle.
So in theory, it's just an extra needle stick.
But I think my patients tend to prefer it.
So I give some, but I try not to overdo it to the point that I distort the anatomy.
And again, my personal preference is a 25 gauge hypodermic needle for these,
some cytologists prefer a little bit larger sample at the expense of some more blood.
And you can use a larger needle.
Some prefer a skinnier needle. I've tried a 27.
I find they're a little bit too thin and have a mind of their own and don't always track true.

I usually do things without suction.
But I do have a syringe at the end of it.
And I will just stop as soon as I see a little bit of blood back in the well of the needle.
If I can't get much back in a pretty avascular lesion, then I'll apply some gentle suction with the syringe.
And last, a trick I've discovered along the way is when I'm doing the biopsy for an FNA,
I do not like to use ultrasound gel.
It puts an artifact on the slides the cytologists really don't like.
And what I do instead is I just take a little plastic tray that usually comes on the biopsy kit
and I just pour some Betadine into that and I just dunk the transducer with a cover on it into that.
And that makes a wonderful acoustic coupler.
You can see very well it's two disadvantages are, it's a little bit runnier and drier,
and patients feel things dripping down the back of their neck.
So I just tell them about that ahead of time and it tends to dry.
But you just, if you just give it a dip before each pass, it really works just fine.
And then the cytologists are very happy 'cause they don't have that artifact.

Typical Tools

So here are the typical tools of the trade.
I think the most common thing I'd use would be a high frequency linear transducer, like this 12 megahertz here.
It's very good. I put the lesion on either one side or the other of the transducer
and bring my needle all the way across the other from the other side.
So it's nice and perpendicular to the sound beam.
You get a good visualization of the needle.
You know exactly where you are.
If the neck little thicker, I might go to a lower frequency linear like this.
If you're working in a tight area and you want your needle to be steeper,
especially if you're doing something like the parotid, I like these little hockey stick style probes
are very high frequency, high resolution.
And lastly, if the neck's really big, or I'm going into the upper thorax or the thoracic inlet behind the clavicle,
I like these little probes that we use for neonatal heads.
We call 'em the baby head probes.
You can stick a needle guide on these very easily and you can get deeper and steeper into infrastructures.
And I'll show you some of those.

Freehand Technique

So this is the basic freehand technique.
This is a very fake picture. I'm not wearing sterile gloves.
There's no betaine on here.
And I don't usually use a long spinal needle like this, but I chose it to sort of illustrate the approach here.
Here's the probe. In one hand, here's my needle. In the other,
the probe is the boss.
You make sure you have lined up the image in a place.
And then the needle has to go where the probe tells it to go.
Not the other way around.
If you need to make an adjustment, you adjust one or the other, but never both at the same time,
or you literally won't have the right hand knowing what the left hand is doing.
I always turn the patient away from the side. I'm doing it.
Stretches the neck out, makes it a little tauter and easier to do.
And this is the sort of image you wanna see fairly perpendicular to the sound beam,
which on a linear is gonna come straight up and down.
And you can see your needle very well.
You can see the bevel at the end.
You can usually see both walls of the needle very, very clearly.

Fine Needle Aspiration vs. Core Biopsy

So, okay, so when do FNA when do you core?
Well, FNA unless I decide I need to core.
And the usual reason is for lymphoma, multiple cores allows a better view of the lymphatic architecture,
which helps out the pathologist.
You can put cores in for flow cytometry.
You can also put FNA in for flow cytometry, but you get more tissue from the core
and you can, it's more, it's easier to get the diagnosis.
I'll core when I get to some strange lesion that the FNA is causing problems
and nobody seems to quite be able to figure out what to do with it.

So a few aspects of the core biopsy needle.
The most important thing is to know the length of throw of the needle.
How far will the core biopsy gun advance?
Two centimeters is sort of standard, give or take a couple of millimeters.
Some are adjustable.
Some come as short as about 11, some will go over three centimeters.
Some you can dial it in.
You always wanna make sure that the throw is appropriate to the size of your lesion.
I also look at the needle tip.
Some of them that just have a blunt beveled needle are very blunt and very hard to get through tissue,
especially in the neck.
A sharper more diamond point style needle is a bit easier to get into things, and I prefer those.
I also think about the stiffness of the spring in these automated devices.
Good stiff spring makes it much easier, especially to get into a very hard lesion.
And some of them are pretty weak springs and they'll tend to recoil on you and you won't get a very good sample.
So a nice stiff spring is nice too.

If you read the literature on which is better and more accurate, I find it's all over the place.
Some say they're equal. Some say a core is better than an FNA.
I think what it really reflects is the pathologist or cytologist who's reading these things.
And that's rather independent of us.
So it's good to get to know who you're working with and how good they are.
And then you will get a better feel for how you need to obtain your samples.
We try to get people to come up and review the samples on site either way,
either by squirting some of the aspirate onto a slide or touching a core onto a slide.
They look at it, they tell us how we're doing.
We know how many more passes we have to do.
If I'm in a thyroid, I usually do about three FNA passes.
Let them look at it. If we're good, we're good.
If they want some more tissue, I'll do a couple more.
My gut feeling is if I do five FNA passes of a thyroid nodule and I haven't gotten much back,
it doesn't matter how many I'm gonna do, I'm not gonna succeed.
I will usually stop.
I think the ultimate answer is, no matter how you do it, you should at least have a minimum 90% specimen adequacy rate,
and probably better than that.
But again, that depends on your cytologist.

Case Examples

Thyroid Mass Misdiagnosis

So here's one where I guess I was a little asleep at the switch as well as the initial radiologist.
This came to me as a thyroid mass.
And this was read by the neuroradiologist.
And so I saw, I said, okay, we'll do, I did my thyroid FNA
and if you look on the ultrasound, it's rather funny looking thyroid mass.
I stuck, did my five passes, didn't get a lot of stuff back.
And the final cytology read on it said, you've got cartilage here.
Like, I know I wasn't and I was in the lesion, not that silly.
So I reviewed my images and I looked at the CT and I looked at the ultrasound,
and actually the thyroid is way over here and is pretty normal.
And you can actually see the crescentic thyroid back here way off to the side.
And the cartilage here is actually irregular and eroded.
And this is a mass actually arising out of the thyroid cartilage.
So I brought the patient back and I did some core biopsies, and we were able to get the final diagnosis of chondrosarcoma.

Another point on him is this patient was extremely hoarse.
And I've seen hoarseness in very, very large thyroid glands, really massive goiters.
But for most thyroid nodules, I'd rarely see significant hoarseness.
This guy was really quite hoarse, and that was because of the cartilage destruction going on.

Lymphadenopathy

So for lymphadenopathy, if you know where the primary cancer is and you're just trying to demonstrate there's nodal disease,
I think an FNA is usually good enough.
And most cytologists will have no trouble with it.
On the other hand, if they wanna have some tumor markers or cell typing,
then you're better off with multiple cores.
18 to or 20 gauge is the size needle I use.
And then the throw is appropriate to whatever the size of the node is.
If you know you're gonna need five or six cores,
you can use a coaxial approach with an introducer needle.
But remember in the neck there's not as much purchase.
So sometimes that coaxial needle will flop around between passes
and doesn't really save you as much work as you might think.

So this is a fairly young boy, 13 years old, had multiple intra parotid lymph nodes here.
There was concern about lymphoma, there was concern about HIV and other things.
Here's what it looked like on ultrasound with some pretty normal parotid and the big hypodense mass here.
So because this was lots of concerns about things like lymphoma, I decided to do a core.
And here's the core biopsy, two centimeter gun advancing forward there.
And you can see it passing through and getting a pure sample of that.

Salivary Glands

So this sort of transitions us to salivary glands.
I'm not gonna talk about salivary gland ultrasound to a great deal except that ultrasound is ideal for salivary glands.
Gives you the best resolution, much better than CT or MRI if it has any limitations.
It's in the deep parotid.
But you can do almost everything you need to do with ultrasound. I think.

This was a 26-year-old who had a mass forward on his cheek.
You can see the vitamin E marker on this MRI here.
And you can see there's a little high signal here, anterior and very superficial to the parotid gland,
which is back here.
And a little enhancing mass here, very tiny.
This was a medical student actually, and he came in knowing what his diagnosis was already.
And an ultrasound, I was able to demonstrate it very well.
So scanning from the lateral face, this would be lateral medial, anterior posterior.
There's a thin track of parotid gland tissue that's right here with this small three millimeter mass at the end of it.
And this is the accessory lobe of the parotid, which occurs very small minority of the time.
It accounts for a small number of the parotid tumors, but you can get any one of them there.
And its location is gonna be on the cheek anterior to this, which is the masseter muscle.
This was too small for me to actually get a decent sample out of 'cause it was so tiny.
But the ENT surgeon was easily able to resect it.
It was palpable.

So parotid gland mass is very easy.
There's a variety of them are the ENT surgeons like to know what they're getting into before the surgery.
It affects their surgery, so we biopsy all of them.
And here's just a simple FNA with a small 25 gauge needle.
You'll notice my needle may extend very slightly out of the lesion when I'm doing the passes.
I think that's okay in the parotid gland.
Parotids are much easier for the cytologist to interpret than say, a thyroid.
So if you get a little normal parotid, it's okay.
I'm very careful in a thyroid gland where the thyroid lesions and the thyroid native parenchyma can be very similar.
And I try and keep my needle entirely in the lesion when I'm there.
Those little hockey stick probes I served earlier are really good for these very superficial lesions.

This is a patient who had had a prior complete parotidectomy for a tumor
and there was a recurrent mass here, very small, only three millimeters,
but I was easily able to biopsy this using the little hockey stick probe
because you can start pretty close to the lesion.
You don't have to go very far.
So you're not gonna make a mistake even trying to get to a very tiny lesion like this.

And just to show a submandibular gland lesion, once again, these are very obvious, easy to see.
Lesions on ultrasound, easy to get a nice core of in this case.

Salivary Gland Botox Injections

So while we're on the salivary gland, I wanna cover Botox injections.
These are somewhat fun and rather useful procedures.
The indication is for excessive salivation.
And it's becoming much more common.
There's a lot of diseases for which this is an indicated technique.
Probably the most common are younger children and adults who have cerebral palsy
or other neuromuscular diseases and have excessive drooling.
You can also see this with patients with Parkinson's disease,
and they can lose up to a liter or two a day this way.
So it can be very useful to them in terms of preventing dehydration and such.

So the Botox comes in a powder, in a vial, it has a hundred units.
What you do is you put one cc of sterile saline in there, which gives you this final concentration of 10 units per 10th of a cc.
Draw it all up in a 1 cc syringe.
And then you want to inject into the three pairs of major salivary glands.
So the parotid, the submandibular, the sublingual, and you can put sort of a variable amount in each.
So a hundred units total for all six glands.
And you can use a 23 or 25 gauge hypodermic.
A lot of these are done in the operating room because between the tremors, the Parkinson's disease
or the difficulties the patients who have cerebral palsy have,
you really need to get 'em pretty still to be able to do this.
You don't want the botulinum to go outside the gland.
But it works very well.
And you can do repeat this every six months to a year if you need to,
if you have more of a musculoskeletal bent, you can inject neck muscles
and you can also do longstanding nerve blocks in those appropriate patients.
I don't really do any of that.

Transoral Biopsy

Just another technique to get to some things here.
This is the transoral biopsy. Seems a little funny.
But we have an FDG positive node way back here at the C1-2 level.
And to try to do this under CT, this would be a very long approach.
Very difficult to do arteries in the way, which are not gonna be enhanced when you try and do the CT scan.
But just like endorectal and endovaginal approaches to things down there, which make it very easy,
the mouth is another orifice that we can use to get close to things here.
So the, because of the nature of the probes, it's best if you do these in the operating room when they're asleep.
And so for these very deep lymph nodes and things, it's very useful.

I pulled these images from this article, which has a very good discussion of it.
Their pictures are better than my own.
So here it is here in the operating room, what we use is we use the prostate probe
and I stick the needle guide on it.
Now we'll just guide a needle right down into this node.
That's right, righteous on the other side of the probe from everything that's very make,
this is very easy to do this way and you have real time visualization.
I just don't tell the patients what kind of a probe we're actually using for this.

Thyroid Gland Specifics

So, been beating around the bush, it's time to come to the 600 pound gorilla of the head and neck,
which is the thyroid gland.
I don't want to talk much about the criteria for biopsy.
I recommend, I tend to adhere to the ACR and SRU criteria.
The American Thyroid Association just came out with new guidelines in 2015,
which were available online.
And I can refer you to those as well, since that's more likely what your endocrinologist may be adhering to.
If you're in Europe or Africa, you may be adhering to the European Thyroid Association criteria,
which are different again.
And so everybody has different criteria that makes it more complicated to know exactly when you should be doing a biopsy.

Just a few sort of personal points.
I think we do way, way, way too many biopsies.
Almost all of them are benign.
It's the only thing we biopsy where it's almost always benign.
The last year that I counted 83 out of my 84 biopsies were benign.
And that was so discouraging, I'll never do it again.
So I believe when you're reading the thyroid ultrasound, take the lead,
tell your referring docs what to do.
Tell them if it needs to be biopsied or if it doesn't need to be biopsied.
They expect this when you're reading any mammography, they expect to be told whether it needs to be biopsied or not.
So why not in the thyroid?

And other, also, when you scan for your thyroid gland, you also want to scan for adjoining lymph nodes,
especially nearby the jugular veins along them.
Really all you need to do is a five second sweep or less along each jugular vein on each side, on everybody.
It takes the tech just a few seconds, less than a minute to do both.
And then you need to report out if there are suspicious nodes as well as suspicious nodules.

When you're looking at a lymph node, you wanna mention its short axis dimension, not its long axis.
Doesn't matter how long it is.
And more importantly is the morphology.
If it looks like a little tiny kidney, it's got a normal morphology with a nice fatty hilum.
If it loses that fatty hilum, whereas abnormal architecture, now it's time to worry about it.
And I'll show you some lymph nodes.

So when you're describing a thyroid nodule, you wanna not only just give the measurements,
you need to give some more description.
An outside radiologist thought this was all calcium in this thyroid gland.
This is not calcium, this is colloid.
You can see the ring down artifact, especially in here.
And you can see there's also a lot of through transmission.
There was no flow in this.
And this was a patient for a bone marrow biopsy, or was gonna be a bone marrow donor, I'm sorry.
And they didn't want to do this until I proved this wasn't a cancer.
So this person had to come in, I had to do this.
I was able to aspirate the entire thing in one pass with the 25 gauge needle was nothing but colloid.

So here's one small lymph node with abnormal morphology.
This should cause be caused for worry.
Even though this one's very, very small and more important than the thyroid nodule,
you should wanna make sure you know what is going on in that.

So when you're doing your biopsy, always know where your needle is.
There are blood vessels in the way you don't want to run into.
Always get perpendicular to your sound beam.
Try and biopsy along the long axis of your thyroid nodule.
Stay inside the nodule.
Usually I point the bevel toward the probe.
You get a little extra echo at the tip that way, and you can pick it up a little bit easier
and you know where your tip is.
I tend not to use suction if it's vascular.
And if I can't get much back, then I'll use some mild suction.
And again, I like a 25 gauge needle.
You may like something larger or smaller.

So here's a nodule here.
The long axis is sort of oriented this way, so it's a little bit faint to see,
but my needle's right here into this.
I wanna come, I wanna approach this one from medial.
You really wanna have the ability to switch hands and approach from medial or lateral,
either direction as the anatomy suits best.

So here's another one.
This is long axis, sort of from the lateral side.
So I wanna approach this from lateral, but I was a little bit worried about the carotid.
I didn't wanna come from medial.
If I went through the nodule, I'd wind up inside the carotid, probably wouldn't be harmful.
I have ventured into there a couple times and don't even get blood back, but it's for form.
So what I did is I elected to come from lateral, and as the carotid sort of seemed to come into play,
I turned my bevel down.
You can see the bevel here.
And since the carotid is pretty thick walled, the needle will actually slide over the wall of the carotid
and not go into it.
You really have to hit the carotid pretty much perpendicularly to get into it.
And so it'll slide right over and pop right into the nodule.

So this is probably the worst thyroid cancer I've ever seen.
Young woman, multiple thyroid nodules, but also innumerable lymph nodes.
Here's a scan, as I was talking about, of the jugular chain lymph nodes.
And you can see there's lymphadenopathy everywhere.
Some of them may have been very necrotic here.
I'll just run it again.
So lots of choices of lymph nodes here.
Rather than worrying about what might be a benign or malignant nodule in the thyroid,
let's just chase down the nodes.
So I tried to pick one of the more solid nodes, and that's what I biopsied here.
It's also much easier for the cytologist if you tell them that you're in a lymph node
because if they see thyroid cells, you know, it's abnormal.
And they don't look like lymphocytes.
Where if you're in the thyroid and you have abnormal thyroid versus normal thyroid,
it's a little more subtle for them.

So again, here's another tiny but abnormal lymph node here between the carotid and the jugular.
It's lost its fatty hilum.
It has these tiny echogenic foci in it.
This patient had three or four thyroid nodules on the same side.
They were all kind of the same in size, all the same in appearance.
I would not have known which one was necessarily gonna be the offender.
And so I might not have biopsied the right one.
But if I just biopsy the lymph node, it doesn't matter.
They're gonna, I get cancer, they're gonna take the whole gland out anyway
and it won't matter which is the primary tumor in there.
So always look for these lymph nodes.
You see this one's not very big, but it's got an abnormal shape.

So you will get some of these indeterminate biopsies.
They come in a variety of names.
This FLUS follicular lesion of undetermined significance you'll run into fairly commonly.
Some of these others you will see as well.
You can read them on the slide here.
And so the good fallback for this is to do some molecular testing.
It adds some specificity to the biopsy.
They look for various gene mutations such as the KRAS and some others.
What you really have to do is just an extra pass or two and put it in a special solution.
And there's a variety of ways you can do this.
You can do this on every patient, put it in the solution.
The cytologist will stick it in the fridge, and if they need it, then they'll send it out to the lab to be done.
Some you can get the patients back on a second day if you need it,
then you don't have to do that extra pass on everybody.
I tend to do it based on what they tell me from the touch prep.
If they think they're gonna need it, then I'll do a couple extra passes.
It really happens maybe one in 10 or one in 20 times.
It's not very often.
This can be expensive and insurance may be an issue if you're somewhere where that matters.

Challenges in Obese Patients

Okay, moving along, the fat neck.
This can sometimes be very problematic even for simple looking biopsies.
My recommendation then is since you need a longer needle, I tend to use a Chiba needle.
You don't wanna use a spinal needle.
It's not really designed for getting a good sample.
And if you really gotta go a long way, a needle guide can make your life much easier.

So here's somebody had this big thyroid nodule.
This looks like this should be pretty easy to do.
It's pretty large. You extend the neck, you lift the chin up, and you're gonna be able to get right in this.
I thought I would, but however, this patient is actually intubated.
And when they finally got him extubated, it turns out he weighed 400 pounds and had obstructive sleep apnea.
And I could not extend his neck and lie him back or he'd stopped breathing.
So I did him almost bolt upright.
I couldn't extend his neck. I had to go through all this stuff.
And then even despite all that, he fell asleep and started snoring while I'm doing the biopsy.
And I didn't get a very good sample.
So I thought I would.
And the reason we were doing this was that the patient actually had a brain mass
and they were somehow convinced that this thyroid lesion was the offending primary tumor
and that he had a brain metastasis.
He had nothing else that was demonstrable as the way of the tumor.
We tried to tell 'em that wasn't the case, but they refused to believe us.
So I told 'em the only way I could get this tissue was if they took him to the operating room and intubated him.
And we did it that way, thinking that would put an end to it since that seemed far too heavy handed.

So a few days later, I'm in the operating room doing this biopsy on the guy who's intubated.
And here it is.
So here's the big thyroid nodule here.
Here's the carotid, which is right here.
I have the needle guide on, and when I was able to extend his neck, it became much easier
and I was able to get the biopsy.
And of course this was benign.

Advanced Approaches

So lastly, to venture a little bit out of the head and neck, but use the neck as an approach.
You can get to the thoracic inlet and the superior mediastinum and even to the lung apex from behind the clavicle.
And again, I like that baby head probe. We showed easier.
I put the guide on and then you scan in a coronal or sagittal or some sort of long axis to the body plane between those two.
And as your needle comes down, you're going to be going parallel to the jugulars and carotids
and therefore they don't come into play.

So here's an example.
Here's a lymph node in this pyramid mediastinum.
This would be very difficult to approach in an axial plane with blood vessels all around it, all the bone.
But when you come from above here it is here.
Very easy lymph node, very simple and straightforward to get into.
Sometimes the vessels can be problematic.
I suppose you could maybe get in through here with the CT, but you wouldn't know where the carotid and the subclavian necessarily were.
But we've got color.
So you can turn the color on, you can see where the vessels are
and you know you're gonna get into your node and not gonna have any problem worrying about anything.

Just another case without a good axial path to get in here.
Lymph nodes here, but here it is on ultrasound.
Here's the jugular and the carotid.
Here's the subclavian artery down here.
Nothing's gonna come into play.
You can even get to the lung apex.
I've done that as well.
And you can biopsy an apical lung tumor the exact same way.

Complications

So just a quick word on complications. They're very rare.
They're usually, in my experience, due to operator error.
Everything is safer than CT because of the real time visualization of your needle
and because you know where the blood vessels are at all times, unlike in CT.
But always keep track of your needle.
Always know where your needle is before you start feeding it forward.
If there's bleeding, just use the ultrasound probe to hold pressure
and it usually will stop within five minutes or so.

So this is one I showed you earlier, but I did this biopsy.
I actually got a small hematoma, you can see it here.
When I put color on initially I could see a little red coming out of the thyroid and into this area.
I held compression for about five minutes. It stopped.
And everything was fine.
And aside from a small hematoma, the patient had no real issues from it.

This happened from one of our residents.
He lost track of where his needle is.
They were going after the cystic lesion with a neural nodule.
He somehow wound up over here in the carotid and rather than just coming in and out of it,
which usually doesn't cause a problem, he actually managed to biopsy the carotid wall
and got this sub adventitial hematoma.
It looked pretty nasty.
This is it in the long axis, I think was more horrifying for us.
The patient really had no symptoms, but it looked pretty ugly like this for about six months until it finally resolved.

And lastly, the other artery you need to worry about in the thyroid is this one here.
This is the inferior thyroid artery.
If you're gonna approach a lesion like this, you gotta make sure you can see this both on color and in a gray scale.
It'll be a little anechoic area.
My fellow managed to hit this and actually we got a pretty big hematoma here
and you can see the artery, which is actively bleeding out.
We held the whole pressure for about 20 minutes and the patient was rather uncomfortable from the hematoma.
And that's about the worst one I've ever seen.
Otherwise, especially if you use Betadine for your FNA chance of infection is virtually zero.
I've never seen it.
And those are really about it for complications.

Conclusion

So thank you.
Here's my email address.
If you have any questions, you can email me.
I'll try and write back with helpful answers if I can.