Ultrasound Guided Intervention in the Abdomen and Pelvis - HD

Ultrasound-Guided Intervention in the Abdomen and Pelvis

Hello, my name is Han Vu,
and I'm a professor of radiology at Oakland University,
William Beaumont School of Medicine.
And today I'm going to talk about ultrasound guided
intervention in the abdomen and pelvis.
Imaging. Guided intervention is definitely experiencing a
period of unprecedented growth with continued advances
in equipment, technology
and refinements in techniques making the procedures safer.
Ultrasound is at the forefront of this trend
and becoming increasingly recognized
as the premier guidance tool for an array
of interventional percutaneous techniques.

Why is ultrasound the guidance of choice for
so many procedures?
The answer is both technological
and economical considerations.
So today I would like to discuss both the traditional
and unique advantages of ultrasound as an image
guidance tool and the utilization
of these advantages in percutaneous ultrasound guided
biopsies and aspiration of intraabdominal and pelvic masses
and fluid collections.

Traditional Advantages of Ultrasound

The many known traditional advantages of ultrasound
as an image guidance tool include real time imaging,
which lead to increased accuracy
with decreased procedure, time
and cost, real time vessel visualization
and multiplanar capability, portability
and availability.
And last but not least, lack of inherent ionizing radiation.
I'm going to use many cases to illustrate these,
traditional advantage of ultrasound
as an image guidance tool.

Case: Liver Lesion Adjacent to Right Ventricle

Here's a patient with a history of lung cancer,
which was found to have a lesion in the dome of the liver
adjacent to the right ventricle,
a biopsy was requested, and the most appropriate
and efficient imaging guidance tool would be using
ultrasound guidance so
that one can observe the needle excursion through the lesion
during real time imaging to ensure that the biopsy
be restricted entirely in the lesion
and not extending to the adjacent critical structure,
which in this case, the right ventricle.
Again, this is the showing the utility of real time imaging
in assisting ultrasound guided biopsy of this lesion
to avoid injury of the adjacent critical structure.
This lesion turned out
to be a metastasis from lung carcinoma.

Case: Small Enhancing Lesion in Cirrhosis

This is a patient with cirrhosis
and there's a small 10 millimeter enhancing lesion
suspicious for a hepatocellular carcinoma Biopsy was
requested, and again, ultrasound with the,
it is a real time imaging,
which permit the operator
to watch this dynamic target move.
And also allowing for the target
and the needle tip to be simultaneously seen in the field
of view before the biopsy to,
ensure the accuracy of the biopsy, which,
yield the this lesion to be a hepatocellular carcinoma.

Case: Perinephric Fluid Collection

Ultrasound can also be used for aspiration
and drainage of superficial fluid collection
as seen in this patient with a perinephric
fluid collection.
So using ultrasound guidance, we can
directly observe under real time imaging.
The needle passing into the fluid collection aspiration
was performed through which a G wire is seen,
traversing the needle into the collection.
And next is the track dilatation
that is being seen when the catheter
or the dilator, it's traversing the G wire.
And finally, the catheter placement
into the fluid collection.
Again, all these steps of this aspiration
and drainage procedure can be visualized at real time
to improve the efficiency
of the procedure.

Case: Pancreatic Head Mass

This is a patient with a pancreatic head mass,
and this mass is adjacent to nearby
large vasculature,
and that's also a large artery
traversing in the middle of the mass.
Under ultrasound imaging, we can use the combination
of gray scale and color flow doppler to avoid
injuring this critical artery
to avoid post-procedural complication.
This lesion turned out to be
pancreatic adenocarcinoma.

Case: Hypovascular Mass Between Hepatic Vein and IVC

How about this case?
This patient has a hypovascular mass, which is situated
between the right hepatic vein
and the inferior vena cava biopsy was requested,
with the multiplanar capability of ultrasound,
we were able to select a safe approach
into the lesion and also,
avoid the nearby vasculature to successfully biopsy
this lesion, which turned out to be a focal
nodular hyperplasia.

Case: Lymph Node in Patient with Breast Carcinoma

The multiplanar capability of ultrasound is also
utilized in this case.
This is a patient with breast carcinoma that is a
small left internal mammary lymph node,
which is suspicious for metastasis,
with CT guidance,
there is a potential penetration
of the biopsy needle into the lung parenchyma,
which may result in pneumothorax using ultrasound.
With this multiplanar capability use with a
steep oblique plane, we were able to
put the needle into this lymph node
and successfully biopsy this lesion with without
complication,
and the lesion turned out to be benign reactive
lymph node, excluding the possibility
or the suspicion of metastatic disease.

Case: Bedside Procedure in ICU Patient

The portability of ultrasound is crucial in patients
who are critically ill
and necessity the procedure to be performed at bedside
as seen in this patient who is in the
intensive care unit.
The patient is intubated,
unstable.
The patient has a chest wall mass
for which a diagnosis needs to be made.
The procedure was performed at bedside,
and here is the arrow that showed the needle in the
chest wall mass again, that the procedure was
safely and successfully performed Confirming the suspected diagnosis
of metastatic carcinoma.

Case: Pediatric Patient with Mediastinal Mass

The inherent lack of ionization is significant
in pediatric and pregnant patient.
This is a 15-year-old with chronic cough
and a anterior mediastinal soft tissue mass
for which biopsy was requested.
This lesion was successfully biopsy under ultrasound guidance, which
confirmed that this patient has
indeed has a Hodgkin's lymphoma.

So we prefer to use ultrasound as imaging guidance
whenever possible, and CT is reserved
for cases in which the lesion is not seen by ultrasound
or the relationship of intraabdominal mass
cannot be adequately established with ultrasound
or when we feel that a safe pathway
to the lesion is unlikely to be found by ultrasound
or when the patient's condition
and cooperation would not make ultrasound guided feasible.

Unique Advantages of Ultrasound Guidance

Right now I'm going to present
to you the unique advantages of ultrasound guidance.
One of the unique advantages is the biopsy
of a very small lesion that is not visualized
with non-contrast CT are only visible
with contrast enhanced CT for a very short period of time,
which is insufficient to allow CT guided biopsy.
Ultrasound also can be used for biopsy
or aspiration of lesion that
are not readily accessible with CT guidance,
particularly in the area of the neck region,
the parotid gland in the periauricular lesion,
and with a variety approaches including transvaginal,
transrectal or transperineal approaches, one can use
for biopsy and aspiration and drainage of deep pelvic masses
and fluid collection.
The use of direct probe compression
to displace bowel loops away from the biopsy targets also
help make a biopsy
of mesenteric masses safe.
And also with the direct probe compression, one can use that
to staunch intraprocedural bleeding
to minimize post-procedural bleeding complication.
And last, but not least, at times,
the quick pre-procedural ultrasound lesion characterization
can serve as a problem solving tool,
providing a reasonably confident diagnosis,
and thus avoiding unnecessary
and potentially risky procedure.

Case: Small Hypodense Lesions in Liver and Spleen

This is an example to illustrate those
unique advantage of ultrasound as the image
guidance modality.
He's a patient being worked up
for a pre stem cell transplant.
On a contrast enhanced CT scan,
there are multiple small tiny
hypodense lesion within the liver and also in the spleen.
Since these lesions were not
present on the previous study, a pathologic
pathology was suspected and a biopsy was requested.
These lesion are not seen on non-contrast enhanced ct,
and as we know, they
are only visible
for a very short period of time after contrast enhancement.
Therefore, would be a
technically challenging if these lesions
are performed with CT guidance.
So ultrasound was used, knowing
that the lesions are there, we were able to localize
several small sub 10 millimeter lesion.
And once the lesion is localized with ultrasound, they
will be persistent
and consistently seen allowing the accurate biopsy
of the small lesions, which
otherwise could not be performed using CT guidance.
And this lesion turned out to be necrotizing granulomas.

Case: Single Small Hepatic Lesion in Patient with Hemangiomas

It's a very interesting case, the patient
with approximately 10 hepatic hemangiomas,
and that is one single eight millimeter lesion deep within
the right lobe of the liver, which looks different
to ring enhancing.
A pet CT was performed, which show
that this small single eight millimeter lesion is hot on PET
suspicious for a metastasis in this patient
with known lung cancer.
So again, this lesion would be very difficult
to be biopsy using CT guidance or probably impossible.
And the ultrasound using anatomic landmark, knowing
where the lesion is,
and also imaging characteristics of
the other lesion being hemangiomas, we were able to locate this
small eight millimeter lesion deep within the right lobe
of liver, and successfully perform a
ultrasound guided biopsy of this small lesion,
which indeed turned out to be a single focal area of
metastatic disease from lung carcinoma.

Case: Parotid Gland Lesion

Another area which is technically challenging,
especially for CT guidance, is the area of the parotid gland
and the periauricular and neck region, as seen in this patient
with sensory neural hearing loss,
and there's an incidental suspicious eight millimeter nodule
within the right parotid
gland. On this MR exam, a biopsy was requested
and this lesion,
which is technically challenging with CT guidance due
to its small size
and location, ultrasound was used
and we were able to confidently localize this
hypoechoic lesion,
for which in ultrasound guided biopsy was performed with
yielded benign reactive lymph node.
And no evidence of malignancy.

Case: Peritonsillar Abscess

Ultrasound not only can be used
for superficial lesion,
but it can also be used for intervention
of a deeper lesion in the neck area,
especially in this area of peritonsillar region.
As seen in this patient who has throat pain
and dysphagia, a CT scan show a suspicious
peritonsillar abscess, which compresses the oropharynx airway,
ultrasound was used
because it's allow us to find a safe tissue plane
through which we can pass a aspiration needle
and avoid the adjacent critical structure.
This fluid collection was successfully aspirated,
yielding purulent fluid, which was
culture positive
for strep of viridans.

Case: Intraprostatic Abscess

This is a also a very interesting case,
highlighting the unique advantage
of ultrasound in intervention.
This patient who has a history of prostatitis
with severe pelvic pain
and recurrent urinary tract infection not responding
to multiple courses of antibiotic.
The urologist was very frustrated as
was the patient.
We recommend an mri.
And on MRI there is a two centimeter
rim enhancing fluid collection within the prostate.
Given the clinical history, highly suspicious
for an intraprostatic abscess.
And due to the location
and the small size of this fluid collection,
ultrasound was performed.
We used a transperineal approach
because the patient had rectal sigmoid colon surgical history, which
did not allow a trans rectal approach.
So the transperineal approach was a use,
and we were able to localize the this fluid collection
and aspiration did indeed yield purulent fluid,
and at the same time,
we instill antibiotic into this abscess.
And the patient experience prompt clinical improvement
during the clinical follow up.

Case: Vaginal Apex Mass in Cervical Carcinoma Patient

This is a patient who is a
30-year-old female with a history of cervical carcinoma
status post total abdominal hysterectomy.
On a routine bimanual exam, the gynecologist
palpated a two centimeter nodularity at the vaginal apex.
The patient was referred for a diagnostic
pelvic ultrasound,
and if possible a biopsy,
if a suspicious lesion was found.
So here is a transabdominal exam, which confirm
a small two centimeter soft tissue mass at the vaginal apex.
And a transvaginal exam, again, confirmed this
soft tissue lesion, which is extremely hypervascular.
And in the same setting, we were able to
perform a transvaginal ultrasound guided biopsy of this
lesion in the area of vaginal apex, expediting the diagnosis
of recurrent cervical carcinoma.

Case: Prostatic Bed Mass in Rhabdomyosarcoma Patient

Here is a 4-year-old boy with history
of rhabdomyosarcoma of the prostate.
He's had a prostatectomy on the routine follow up.
A new mass was seen in the prostatic bed,
suspicious for a recurrence.
Instead of using a gluteal approach to access this lesion,
we used a trans rectal approach.
And with the trans rectal ultrasound, the mass was
readily visible and through to which
we were able to biopsy this
soft tissue mass within the prostatic bed confirming
recurrent rhabdomyosarcoma.

Case: Mesenteric Mass

Now, another unique advantage of ultrasound
guidance is the use of direct probe compression,
as seen in this case, this is a patient with abdominal pain
and a mesenteric mass biopsy was requested.
We use ultrasound as a guidance tool
and with direct compression using the ultrasound probe,
the bowel loops could be
displaced away from the target.
At the same time decrease the distance between the
skin surface and the target lesion,
allowing safer biopsy of this mesenteric mass,
which turned out to be a benign reactive node without
malignancy again in the doing.
So we were able to avoid the potential
injury of the adjacent bowel loop,
which may cause perforation of a viscous organ.

Case: Oozing at Paracentesis Site

The utility of direct probe compression is also
illustrated in this patient who complain
of oozing at the paracentesis puncture site.
The patient was brought down
and scanned, color flow Doppler show a small active
bleed at the puncture site
and with direct compression using ultrasound
over the bleeding site.
After 10 minutes of direct compression, we were able to
stop the oozing
and the cessation
of active bleeding was also confirmed at real time color
flow Doppler imaging, the use
of direct probe compression over the biopsy site when there is no intervening bony structure
to manage intraprocedural hemorrhage is also extremely helpful as seen in this patient
who we perform a biopsy of a native kidney,
in the immediate post procedure
and under real time, there is a
small perinephric hematoma,
but more significantly, there's a small active bleed,
direct compression using probe upon the
biopsy site was utilized,
after 10 to 15 minutes of compression.
The active bleeding was stopped.
Perhaps is the combination of direct probe compression
and the tamponade effect
and the time that allow platelet aggregation.
Maybe the combination of all of the factors above help
manage this active bleeding that was visualized
intraprocedurally
and minimize
post-procedural complication is seen in this case.

Case: Rim Enhancing Fluid Collection Mimicking Abscess

This is also an interesting case highlighting
another unique advantage of ultrasound guidance.
So here's a patient with abdominal pain.
CT scan show a rim enhancing fluid collection in the pelvis,
suspicious for an abscess, aspiration
and drainage was requested.
So during the quick routinely performed pre-procedure
ultrasound imaging, we realized that this
fluid collection actually corresponding to the ovaries,
both right left ovaries that were
positioned in the cul-de-sac,
which simulate the fluid collection on the ct.
So with the
and there was no fluid collection in the pelvis.
So using the lesion characterization
during the quick pre-procedure ultrasound scanning,
we were able to avoid the aspiration
and drainage procedure which is
also a potentially risky procedure in the this patient.

Case: Enhancing Renal Mass

Another example to highlight the unique advantage
of ultrasound seen in this patient who, on an
outside study show,
a 12 millimeter enhancing renal mass biopsy was requested,
during the pre-procedure scanning, again, the mass is extremely echogenic,
suspicious
for a benign angiomyolipoma.
We take the patient over to CT scan.
A few limited scans were obtained through the lesion,
which confirm intralesional presence of fat,
consistent with an angiomyolipoma.
Therefore, a biopsy was not performed.
So a time pre the pre-procedure ultrasound scanning
with the lesion characterization can provide a reasonably
confident diagnosis, which allow us to avoid
performing an unnecessary
and risky procedure as seen in this case.

Case: Multiple Hepatic Lesions in Renal Cell Carcinoma Patient

How about this patient who has a known renal mass,
suspicious for renal cell carcinoma,
and two hypodense lesions within the liver, suspicious
for hepatic metastasis, biopsy.
The liver was requested during the scanning.
The lesion in the right lobe appeared
to be extremely echogenic with possible
through transmission, a suspicious for a benign hemangioma
of the liver,
scanning the second lesion in the left lobe,
show a more suspicious well defined hypoechoic lesion
with the imaging characteristic.
The second lesion was chosen to be biopsy,
which indeed turned out
to be metastatic renal cell carcinoma.
And the first lesion was indeed later on shown
to be a hemangioma.

So this unique advantage of ultrasound lesion
characterization really highlights the benefit in the lesion
selection in patient with multiple lesion to improve the
diagnostic yield.

Case: Hypodense Hepatic Lesion

Another patient with a hypodense lesion done an
outside CT scan, refer for biopsy on the day of the biopsy.
The lesion seemed to be
or appears to be echogenic with some lobulated margin,
probably a hemangioma.
So should we proceed with the biopsy or should we stop
and recommend an MRI?
The lesion characteristic is
very suspicious for a benign mass.
So we recommended an MRI, which was performed
during the next day,
and in this MRI proved that lesion turned out to be a hepatic
hemangioma
with a typical characteristic on the T2
and contrast enhanced images.
This patient therefore did not have a necessary
biopsy procedure of this benign hepatic hemangioma.

Technical Highlights

So at this time discuss a few technical highlights
concerning liver and renal biopsy and transvaginal
and transrectal biopsy and aspiration of lesion
and fluid collection.

Liver Lesion Biopsy

With regard to a liver lesion biopsy,
a sub costal approach is always preferred when possible
because it eliminates the risk of pneumothorax
and the potential laceration of intercostal vessels.
But it may require steep needle angulation.
Subcostal approach is excellent
for lesion in the left lobe
and in the mid to lower portion of the right lobe.
But an intercostal approach usually has
to be used for lesion which is high in the dome.
It's also pretty safe.
It rarely results in pneumothorax
unless the lung is transgressed.
When performing a liver lesion biopsy,
we should avoid direct puncture into the lesion by choosing a path with intervening normal liver
for a tamponade effect,
and to minimize post-procedural bleeding complication.
And if that is brisk bleeding
during the procedure, we often use a coaxial approach with
a 17 gauge introducer
and 18 gauge biopsy needle if
that is a brisk bleeding
or blood return from the introducer.
We use a compression
or a combination of compression when possible
with autologous clot
or a procoagulant agent if needed such
as a thrombin or gelfoam.

Here is a patient with a subcapsular lesion
somewhat high in the liver.
A subcostal approach was used,
but it did require steep angulation,
but we were able to reach the lesion
and successfully
and safely perform the biopsy of this lesion,
which turned out to be a hepatocellular carcinoma.

Here's a patient with a very high lesion in the dome
of the liver, so an intercostal approach had to be
utilized, but this is relatively safe as long
as the lung is not transgressed,
and the lung can be readily seen at a real time.
But as you can see here, this echogenic structure that is moving with respiration, with the
the lung and the lung edge,
and we should avoid transgressing that
and avoid the pneumothorax as a potential complication.
So here is a biopsy of large hypovascular hepatocellular carcinoma.
We did choose the path that through a intervening normal liver parenchyma,
but that was very brisk bleeding through the introducer.
After the procedure in this circumstance,
you can use the autologous clot to help
stop the bleeding or the use a procoagulant.
In this case, we use thrombin to embolize the track,
and we were able to stop the bleeding
during the procedure.
And this patient also did not develop
post-procedural bleeding complication.

In contrast to this large
hepatocellular carcinoma.
Unfortunately, a direct puncture approach was used.
And immediately
after the procedure, the patient experienced extreme pain,
hypertension consistent with
hemorrhage.
A contrast enhanced CT was performed that show active extravasation
and a large amount of hemoperitoneum in this patient
with active bleeding.
The patient was immediately taken over
to the angio suite.
A active bleed was found
and was successfully embolized using coil
embolization.
So definitely one should try to
avoid direct puncture, especially
of the hypervascular lesion such
as hepatocellular carcinoma to minimize post-procedure
bleeding complication.

Renal Biopsy

With regard to native
and transplant renal biopsy, one should
choose a safe trajectory or needle path.
And the needle path should point toward the
polar cortex, preferably the low pole.
You can also use the upper pole as long
as the needle path is only pointing to the pole
and not directly into the renal hilum,
which increased the risk of post-procedural hemorrhage, as seen in this case, with a risky needle
trajectory that directly into the renal hilum, which
resulted in a post procedure perinephric hematoma.
Additionally, the pathologist only need the cortex and not the medulla.
So again, the needle path should be pointing into the cortex of the polar area of the renal parenchyma.

One of the significant complication of renal biopsy in that of a formation of an arteriovenous fistula,
many time a very small fistula will spontaneously thrombose without a significant symptom
or at time.
A large arteriovenous fistula may also result,
which require embolization,
but sometime even a small arteriovenous fistula can also be very symptomatic as seen in this patient
with a small AVF,
but with gross bloody hematuria,
which did not stop.
And the patient was severely symptomatic.
The patient was taken
to the angio suite confirming a small arteriovenous fistula,
which was then coil
embolized.

Transvaginal and Transrectal Approaches

Trans rectal
and transvaginal approaches can also be used for access
deep pelvic masses and fluid collection.
It's relatively safe, somewhat less painful
for the patient compared to gluteal approach.
So when the gluteal approach could not be used, transvaginal
and transrectal approach could be utilized if one is the using trans rectal approach.
Antibiotic coverage prior to the procedure is
strongly recommended to prevent post procedure
biopsy risk of
abscess formation.
We routinely perform these
procedure under conscious sedation.
So an endocavitary probe is used,
and there are a number of adapter
or devices that can be attached to the probe to
help simplify the procedure, either
with either for aspiration catheter drainage or a biopsy as illustrated in this case.

This is a patient with a history of ovarian carcinoma on the routine follow up that is a suspicious, solid
and cystic mass Concerning for recurrence, trans rectal ultrasound guided biopsy was performed,
again, confirming both the cystic
and vascular solid component of the mass.
Through the trans rectal approach,
we aspirated the cystic component
and also biopsy the solid component.
And both yielded recurrent ovarian carcinoma.

Ultrasound guided trans rectal drain placement could
also be used to manage deep pelvic or perirectal abscess as seen in this patient
with a perirectal fluid collection, suspicious
for an abscess, via trans rectal approach.
We can see this complex fluid collection, through which a needle can be placed into the fluid collection for aspiration
and confirmation of a purulent fluid.
Then through a trocar approach the catheter can be placed into
this fluid collection.
As you can see here, as the trocar catheter inserted into the abscess collection
and placement of the catheter was then can be done and on
and the ultrasound that the catheter was confirmed
to be the fluid collection during several days
after the catheter placement of CT was performed confirming complete decompression
and drainage of this per rectal abscess.

Conclusion

So, in conclusions, ultrasound is increasingly recognized
as the primary imaging guidance tool
for many interventional procedures, due
to its many advantages over other guidance modalities.
And as equipment technology continues to improve, the shift
of procedures away from CT guidance will continue,
and ultrasound will become the guidance of choice for most
interventional procedures.
Thank you very much for your attention.