Ultrasound Guided Abdominal Biopsies: Lessons Learned - Part 2

Liver Biopsies

For doing liver biopsies, we're obviously looking
for either getting a piece of the parenchyma to evaluate
for parenchymal disease, or we're going to be going
after a mass to diagnose either hepatocellular carcinoma
or metastatic disease.

In doing the biopsies for parenchymal disease
of the liver, I usually go in the supine midline subcostal approach into
the left lobe of the liver.
If the patient has a very small left lobe of liver,
then it may not be possible,
and you may have to put the patient in the left decubitus
position and use an intercostal approach.
I personally don't like to use this approach
because this approach hurts much more than going
through the subcostal midline approach.

Here we have an example on the left of using a 23 gauge,
millimeter throne needle.
And as you can see in this instance, when you,
you can see the needle go into the liver
and you can see the, how far it goes down.
In the old days, I used to do two biopsies like this,
but then I went and used a 33 millimeter throw needle.
And when you do a biopsy with this,
you see you get a much deeper core of tissue
and you need only do this once.
So that's why I like the deeper throne needle.

When I am going after a biopsy
for parenchymal liver disease, when I wish to biopsy,
a mass within the liver, I use a coaxial needle.
I bring the needle tip down to the mass
and I'd like to biopsy
or I like to insert this needle through a cuff
of normal tissue, and I explained why in just a moment.
If the mass is very large,
I will biopsy the outer margin.
If it's a small,
smaller mass, I will just go through the center.
Obviously in a larger mass,
if one head towards the center right away,
you may just get back necrotic tissue.
So we don't want that. So having once got the coaxial needle
into place, I insert the cutting needle
through the coaxial needle down to the mass.
I then will suspend respiration
and then I will fire off the needle and withdraw.

In this instance here we have a patient with a,
with the history of metastatic breast carcinoma,
who has a small mass lesion in the liver here,
and we're trying to make the diagnosis
of whether this is a metastatic lesion.
And image on the left here,
I did a fine needle aspiration again
by inserting the quain needle into the mass
and then doing my fine needle aspirations here.
And then I followed this with two core biopsies,
again using the quain needle as my guide.
So it's emphasizing the use of the quain needle
as allowing you to take as many biopsies as you wish
with just one insertion of the needle.

This is a patient with lymphoma, again,
with a small lesion in the liver as we can see here.
And then when we go to here, you can see the,
coaxial needle is here,
and then you can see the, the fine needle being inserted
through the coaxial needle
to take a biopsy from this lesion proving
that this was in fact lymphoma.

Now there's always been a debate about whether you can do a
core biopsy of the liver when there's a lot of ascites,
and it's been well shown that the risk
in doing a core biopsy is no greater
whether you have ascites or not.
It can be technically more difficult
because of the fact that if you have a cirrhotic liver
that is somewhat hard with a lot of ascites, it can be hard
to get the biopsy needle into the liver.
But even so, I rarely have to withdraw ascites
to do this kind of biopsy.

Now, this is an example of a vascular mass
in the liver in a patient
who has a cirrhotic liver and ascites.
And here we have our ultrasound here showing the
mass within the liver.
And here we have our biopsy here.
As you can see, again, I put a coaxial needle
through the liver down to the level of the mass.
And then through that I've taken my core biopsies to prove
that this patient did in fact have
hepatocellular carcinoma.

Now, I don't like the biopsy lesions on the surface
of the liver because of the fact,
especially if they're vascular, they can bleed.
And in this example, this was an HIV positive individual
with hepatitis B with a cirrhotic liver
and a vascular mask, very suspicious
for hepatocellular carcinoma.
So I went ahead and did my biopsy
and then following the biopsy, lo
and behold, the patient bled, as you can see here,
there's some blood off in the acidic fluid at this point.
And obviously this demand that then he had to be
embolized following this biopsy.
So I learned a lesson from this not to biopsy
vascular lesions on the surface of the liver.
If at all possible, I would always try
and make my way through a cuff of normal tissue.
So the lesson I would've learned on this image here is
that I would've brought the needle in from at an angle
to this lesion rather than straight down to, to avoid,
biopsy on the surface of the liver using a cuff
of normal tissue to help you get a biopsy without
having any bleeding complications.

Pancreatic Biopsies

Now onto
pancreatic biopsies.
As you know, we are in competition
with endoscopic biopsies
and also with a CT to do these types of biopsies.
And I must admit that I don't do
as many pancreatic biopsies as I used to do in the past.
The reason is that endoscopy has taken over
and is a very safe and effective procedure
in certain cases.
However, if you have liver lesions,
it's probably wise the biopsy to the liver lesions first
because you will prove that the, so
that the mass in the liver,
let's say on a CT scan is in fact a metastatic
pancreatic cancer to the liver.
And obviously in performing a liver biopsy,
it's a lot safer than doing a pancreatic biopsy.
Also the other problem that you're having biopsying
and pancreatic mass is
that you often will have associated inflammatory changes
with the cancer, which can prevent the
accurate diagnosis of cancer
among all these inflammatory changes.
And as I said already, there is an increased rate
of complications from biopsying these pancreatic masses in
comparison to the liver.

If one has to biopsy the pancreas, for example,
if an endoscopic biopsy has failed
and you don't a liver metastasis,
then I would obviously biopsy the head
and body with the patient in the supine position.
If the mass is in the tail,
I would use the right decubitus position going through
and inter or using an intercostal approach.
In the supine position, sometimes it can be hard
to see the pancreas
because of the presence of gas within the stomach.
So in that instance,
I will actually have the patient drink some sterile saline
and distend the stomach
and then use the water in the stomach as kind of a
ultrasound window to the pancreatic mass.
Again, making sure
that you switch your color doper Doppler on
to watch out for vessels.
'cause these pancreatic masses often have small vessels on
their surface and you wish to avoid that
and not have the patient bleed.

This is just an example
of a pancreatic biopsy using a CT guidance.
Now we generally would only biopsy lesions
that we deemed to be unresectable
because if they're deemed to be resectable,
then they should be surgically excised.
Here's an example of biopsy of a,
a large mass in the pancreatic tail, you will identify
that I'm actually using the ultrasound to identify
the stomach wall, which is over here,
and the omentum, which is here.
I would switch my color doppler on,
make sure there are no vessels in the omentum,
and I will go through the omentum into the masses.
You'll see here proving
that this is a pancreatic cancer involving the tail.

In terms of the accuracy
of ultrasound r CT in providing a diagnosis
of a pancreatic mass, it's pretty good actually.
We make a diagnosis up to 95% of the time.
Again, the complication rate is quite high at 2.6%.
The rate is not as high in the liver,
nor is it even this high within the kidney.