Anomalies of the Fetal Thorax - HD

Introduction to the Fetal Thorax

Hello, my name is Dr. Carol Benson.
I'm from Brigham and Women's Hospital in Boston
and Harvard Medical School.
Today my lecture will be on the fetal thorax.
The fetal thorax is the upper part of the fetus,
the upper part of the trunk.
It's supported by the spine and ribs
and it's separated from the abdomen by the diaphragm.
Within the thorax are vital organs including the heart,
the lungs, and mediastinal structures.

We can see the diaphragm on ultrasound on a
sagittal view of the fetus.
You can see here in this 18 week fetus
that we don't see the diaphragm itself,
but we see the configuration of the diaphragm as the contact area between the abdominal contents
and the more echogenic liver.
By the third trimester though,
we can actually see the diaphragm itself as a band
of muscle separating abdominal contents from the thorax.

When evaluating the fetal thorax with ultrasound,
we want to look at the supporting structures
to make sure they're normal.
We want to look at internal organs
to make sure they're in the normal position.
We want to make sure the internal organs
that we see are normal and we want to look for any masses
or cysts or fluid that shouldn't be there.

Supporting Structures of the Thorax

We'll start by talking about the supporting
structures of the thorax.
The supporting structures are the spine and the ribs.
And you can see here on these two 3D images of the fetus,
you can see the spine with the ribs coming on either side.
And it's important that these are intact
to support the growth of the fetal lungs.

This fetus has an abnormal thorax due to abnormal structure
of the ribs and the spine.
This fetus has agenesis
and you can see that the thorax is very small.
Notice that the AP dimension
of the thorax is much narrower than that
of the fetal abdomen.
And on transverse view of the thorax, we can see
that the heart is filling up most of the chest.
And the rest that we see on this view is abdominal contents
that are partly on that cross section.

We also want to look for defects in the thoracic wall.
These may be isolated defects
or they may be defects
through which the heart has herniated out of the chest.
And this is called ectopia cordis.
They may be a large defect in the anterior thoracic wall
that may also involve the anterior abdominal wall in a
lesion called pentalogy of Cantrell
or the thoracic wall may be disrupted by amniotic bands.

Here's a 13 week fetus with a ventral wall defect.
In the thorax, you can see that the heart is herniated
outside of the chest.
On the gray scale image, we see the heart beating
outside the chest, but communicating
through a defect in the thoracic wall
to the rest of the fetus.
And on the color you can see the blood flow in
that beating heart as well as in and out of the thorax.

With pentalogy of Cantrell,
we have a large anterior defect involving the
thorax and the abdomen.
The abdominal component is an omphalocele, but the omphalocele
and the cleft extends all the way up into the thorax
with a cleft in the sternum.
In addition, there'll be a defect in the anterior diaphragm
and often the heart is extruded from the chest.
As in ectopia cordis.
It's common that cardiac anomalies are present in these
fetuses including ventricular septal defects
or left ventricular diverticula.

So here we have a fetus with pentalogy of Cantrell.
You can see on an axial view at the level of the lower chest
that we have the lungs here posteriorly
and we have the heart sitting crossing that defect.
So it extends from the anterior part of
where the thorax should be out into herniated contents.
And these herniated contents are both abdominal
and thoracic contents.
On the longitudinal view,
you can see this large ventral wall defect.
It looks like an omphalocele except
that it extends all the way up into the thorax.
And again, you can see
that the heart is herniated into the base of the defect
and the herniated contents, this is a 3D view of
that fetus showing this very large herniated sac from the
large anterior defect.

Evaluating Position of Internal Organs

Now once we've determined
that the supporting structures are intact, we move on
to look at the internal organs
to make sure that they're normal.
We also make sure that their positions are normal.
So we'll start by looking at position.

There's a lesion called situs ambiguous or heterotaxy.
And this is when the organs
of the thorax may not be in their normal orientation.
Things that should be on the right,
may be on the left and vice versa.
And these cases often have multiple anomalies,
particularly involving the heart as well
as abdominal structures and thoracic structures.

So here's a fetus with situs ambiguous.
You can see on the clip when it's up in the region
of the thorax that the heart is on the left hand side,
which is normal and pointing to the left.
But as we scan down into the upper abdomen, we see
that the stomach is in the
right upper quadrant rather
than the left upper quadrant.
And we see that the umbilical vein comes in on the left side
of the abdomen.
So the liver is left sided,
so abdominal organs are in the reverse position,
but the thoracic organs are in the normal position.
So this is situs ambiguous.
This would be a case where we'd want to look carefully
for other anomalies.

This fetus does have heterotaxy as well.
You can see in this case on the transverse view
of the thorax that the heart is pointing to the right.
We can also see that the heart is clearly anomalous
with a large defect in the central portion of the heart.
This was an atrioventricular canal.
When we look in the fetal abdomen, we see
that the stomach is in the right upper quadrant.
So this is again situs inversus
and we see that the gallbladder in the liver
and the left upper quadrant.

When evaluating the position of structures
inside the chest, we don't just want to see if they're on the
right or the left side, but we actually want to see if they're
in the proper position in the chest.
And this involves looking at the heart
to make sure it's positioned properly behind the sternum.
In normal position with normal orientation of the apex
and the base of the heart, one of the ways to do this is
to get a transverse view of the chest
and then just draw a line
from the spine up through the heart.
And if we do this, you see on the diagram as well
as the clip that the line should cross through the spine,
the descending aorta, then through the left atrium, then
through the right ventricle when it comes in
contact with the sternum.
And so here we see on this clip
that our line passes through the appropriate organ.
So this heart is in normal position.

We also look at the lungs to make sure
that they're homogeneous on either side.
So here's a case where it looks like the heart might not
quite be in the normal position.
So we'll draw our line from the spine all the
way up to the sternum.
And we see when we do this that the line passes not
through the descending aorta,
but just to one side of the descending aorta
and it then passes through the left ventricle rather than
the left atrium and the right ventricle.
So this heart has been displaced to the right side.
And if you look a little more closely, you can see
that the tissue on the left side is heterogeneous.
This fetus has a diaphragmatic hernia on the left
with bowel herniated up into the chest.

Congenital Malformations of the Lung

Now once we've evaluated position,
we now look at the internal organs
and this would involve looking at the heart
and the lungs.
But we're primarily going
to focus on the lungs during this lecture.

When looking at the lungs, we can look
for congenital malformations of the lung
and these can be put into a general category
of pulmonary dysplasias.
Pulmonary dysplasias can involve the lung tissue
but can also involve the blood supply to the lung.
So we may have for example, a lung abnormality
where the lung parenchyma is normal,
but that portion of the lung is fed
by a systemic vessel rather than a pulmonary vessel.
And this is what we would classify
as a classic sequestration.

There may be situations
where the lung parenchyma itself is abnormal,
but it has systemic blood supply.
And this would be a combination of
the cystic pulmonary airway malformation
and a sequestration.
Or we may have a situation that has abnormal lung
but pulmonary blood supply
and this would be a classic cystic pulmonary
airway malformation.

Other abnormalities that can affect the lung are listed here
that we can have tracheal atresia,
we can have bronchial atresia, bronchogenic cysts,
bronchopulmonary dysplasia with neuroenteric abnormalities
and we can have pulmonary agenesis.
And all of these are things
that we consider in our differential diagnosis when
the lungs appear abnormal.

Congenital pulmonary airway malformation is one
of the most common anomalies of the fetal lung.
This can be classified into types one, two,
and three based on how large the cysts are
that we visualize inside this abnormal portion of the lung.
If the cysts are very large measuring more than two
centimeters, prognosis is generally good
and that would be classified as type one for smaller cysts,
those that are still visible by ultrasound, these cysts
that measure less than two centimeters, this is classified
as a type two and has a worse prognosis
because it may be associated with other anomalies.
And the type three congenital pulmonary airway malformation
appears as a large solid echogenic mass.
And for these, the prognosis is poor due
to pulmonary hypoplasia
because the large solid mass compresses the normal lung
tissue congenital pulmonary airway
malformations can change in utero.
About 50% will even regress,
particularly the type ones more often than the
type two or type three.
Overall when evaluating a congenital pulmonary airway
malformation, the prognosis is worse if the fetus develops
hydrops or if we see associated anomalies.
But in general, overall the prognosis is quite good.

So here's a fetus
with a congenital pulmonary airway malformation type one.
You can see a very large cyst in the thorax of this fetus.
This is the left side of the fetal chest
and it's not just the cyst that's part of this malformation.
The entire left lung visible on this view is abnormal
as we can see here.
And here it's more echogenic than it should be.
So this is all abnormal tissue notice too
that the diaphragm is inverted due to compression
and pressure from this large mass filling the left thorax
and shifting the heart over to the right.

Now whenever we see a congenital pulmonary airway
malformation, we do want to assess the blood supply
to this lesion.
Here we see in this particular case
that the arterial flow is via the pulmonary artery
and the venous return is via the pulmonary vein back
to the left atrium.
And no vessel feeds this from the descending aorta.
So this is a normal pulmonary blood supply.

This fetus also has a type one congenital pulmonary
airway malformation.
We first saw it at 18 weeks
where it involved the posterior aspect of the
right side of the chest when this patient came back at 23 weeks.
Now we have that the right side
of the chest completely filled
by this large abnormality.
It's echogenic, it has multiple cysts, it's compressing
and pushing the heart
way over to the left side.

This fetus has a type two pulmonary airway malformation.
You can see on a transverse view of the chest
that the heart is displaced to the right side.
You could see if we were to draw our line
through the sternum back to the spine that the
aorta is pushed way over to the right side
and it's being pushed by this echogenic mass filling
the left thorax and within this mass are these
small cystic spaces.
The mass does not fill the entire left thorax.
There is some normal lung in the upper part of the thorax,
but it occupies the middle
and lower portion of the thorax as we see here on this view.

So what we will do again is assess the blood supply.
And here you can see in this type two pulmonary airway
malformation that the blood supply here is via a pulmonary
artery and the venous return is via a pulmonary vein.
So again, this is a classic congenital pulmonary
airway malformation.

This fetus has a type three pulmonary airway malformation.
The left side
of the chest has a large echogenic mass displacing some
small amount of lung, plus the heart over to the right side.
This lung had no cysts in it then
that's why it's a type three malformation.
We see on the color that it's fed by a pulmonary artery
and it's drained by a pulmonary vein.

Many lesions though were mixed, many
of them are congenital pulmonary airway malformations with
abnormalities of the lung parenchyma,
but have a systemic blood supply like a sequestration.
And here is such a case here at 18 weeks gestation,
we saw an echogenic mass in the left chest displacing the
heart to the right side.
We can see normal right lung behind the heart by 20 weeks gestation.
We saw within this echogenic mass a few small cysts.
So this is a type two congenital pulmonary
airway malformation.
We're now going to go look at the blood flow to this lesion
and we see on a longitudinal view of the aorta,
an isolated vessel feeding this congenital pulmonary
airway malformation.
So this is systemic arterial blood supply
into an abnormal lung region
with abnormal lung parenchyma.
We assess the venous return from this lesion
and see that it's a normal pulmonary venous
drainage into the left atrium.

Now classic pulmonary sequestration are when you have a
segment of the lung that appears otherwise normal
but has a systemic arterial blood supply.
Often these have no tracheal bronchial communication
and they may be intrapulmonary
or extralobar depending on whether they're within the lung
pleura of the rest of the lung
or whether they have their own pleura.
They may be actually above or below the diaphragm
and most of them are in the left lower lobe posteriorly,
that's the most common site.
About 90% of them will be here.
They may decrease in size during gestation.
About 25% have pulmonary venous return
and about 75% have systemic venous return.
In general pulmonary sequestration have,
are a wedge-shaped lesion and
they do not cause much mass effect on the
other structures in the chest.

So here's an example
of a right-sided pulmonary sequestration.
We see that it occupies the posterior inferior aspect
of the right thorax
and it's this wedge shaped lesion on longitudinal view
and it's this wedge shaped lesion posteriorly
on the transverse view.
Notice that the heart is not significantly pushed
over to the left.
We confirm that it's a sequestration by looking at a view
of the descending aorta
and finding an isolated arterial branch feeding this
segment of the lung.

Here's a case with similar findings except
that the sequestration is causing more of a mass effect.
We see on a transverse view of the chest
that the heart has been displaced to the right
by this large echogenic mass
in the left thorax.
On longitudinal view,
this mass is triangular shaped like the shape
of the left lower lobe of the lung.
When we look at a longitudinal view of the aorta,
we see an isolated systemic vessel feeding this wedge
of lung in the left chest.
So this is a sequestration,
but this one had more of a mass effect than some do.

I mentioned the sequestration can be below the diaphragm.
When they are, we see a homogeneous echogenic mass located
above the kidney but below the level of the diaphragm.
And so in the differential diagnosis, we do need
to consider an adrenal lesion here on this transverse view
of the upper abdomen, we see an echogenic mass,
well-defined located in the left upper quadrant,
a longitudinal view.
We can see that lesion in the left upper quadrant.
We can see that it's below the diaphragm
and does not appear to be related
to the lung tissue on that side.
A view of the blood flow
to this lesion shows an isolated vessel coming directly from
the aorta into this lesion.
Here we can see it here as well on the transverse view.

There can be mixed lesions below the diaphragm just like we saw mixed lesions
above the diaphragm.
Here we have a patient who has a mass above the kidney
below the diaphragm in the region of the adrenal gland.
This mass is complex, it has cystic areas
and echogenic areas
and this proved to be one of those combination lesions
of a sequestration with parenchymal changes
of congenital pulmonary airway malformation.

Bronchial atresia is in the spectrum of
pulmonary dysplasias.
It's when there's obstruction of one of the bronchi
and it leads to enlargement of the lung distal to the
obstruction and the lung will be very echogenic.
The lung can expand in size causing a mediastinal
shift and mass effect.
And if the mass effect is enough,
it may cause polyhydramnios and even hydrops.

So here we have a fetus with bronchial atresia.
On the right side we can see that a longitudinal view
of the right chest shows a homogeneously echogenic right
lung with flattening of the diaphragm on transverse view.
We see the right chest is filled
with an echogenic mass displacing the heart far
to the left side with only a little bit
of residual left lung tissue adjacent to the heart.

Tracheal atresia is when there's obstruction of the trachea and therefore we get expansion enlargement
and increased echogenicity of both
of the lungs in the chest.
This results from accumulation of fluid inside the lungs
and so there's increased pressure in the chest which can
lead to polyhydramnios due to decreased venous return
to the heart as well as obstruction to swallowing.
In addition, because of the obstructed venous return
to the heart, we may see signs of hydrops.
Particularly we may see ascites in the fetal abdomen.

So here's a case of tracheal atresia.
You can see on the transverse view of the chest
that the heart is compressed into the midline
by these very echogenic lungs on either
side of the heart.
And we can see fluid in the dilated bronchi
that are obstructed by the tracheal atresia.
Looking in the abdomen,
we see ascites in the fetal abdomen due
to obstructed venous return to the heart.
On longitudinal view of this fetus, we can see
that the lungs are so big
and forcing so much pressure on surrounding structures
that they're causing inversion of the diaphragm.
We also can see again the ascites accumulating in
the fetal abdomen.

Intrathoracic Masses, Cysts, Fluid, and Diaphragmatic Hernia

Now we also want to look for things in the chest
that shouldn't be there, such as masses, cysts, or fluid.
An intrathoracic mass can be caused
by several different things,
but the ultrasound findings will be similar.
We'll see a mass, we may see mediastinal shift.
Depending on where that mass is, it will likely
compress normal lung
and depending on its size, may cause hydrops or pulmonary or
polyhydramnios.
Overall, the prognosis for a fetus
with an intrathoracic mass is related to the degree
of pulmonary hypoplasia and whether
or not hydrops is present before birth.

One of the most common causes
of a mass in the chest is a diaphragmatic hernia.
These result most commonly from defects in the foramen
of Bochdalek in the diaphragm
and they're more common on the left than the right side when
they occur on the left stomach
and bowel herniate up into the chest when they occur on the
right, the liver may herniate up into the chest.
There is a very unusual form of diaphragmatic hernia,
which is a defect anteriorly
and in the midline at the foramen of Morgagni.
And in these cases we may see stomach, bowel
and liver herniate up into the chest.

Here's a diagram of a diaphragmatic hernia.
You can see that when there's a defect in the posterior
aspect of the diaphragm,
that abdominal contents herniate up into the chest
and so the stomach will flip over so that the fundus
of the stomach will be just above the herniation
and the distal stomach will be higher up as will loops
of bowel which will be trapped up into the chest.

Overall. When evaluating the diaphragmatic hernias
with ultrasound, there are findings to look for
that indicate a worse prognosis.
One of them is polyhydramnios.
Another is if they're associated anomalies
particularly of the heart.
The earlier the diagnosis.
In general, the worse the prognosis
because those are likely to be larger diaphragmatic hernias
and larger hernias are those
with large volumes herniated up into the chest have
a worse prognosis.
Mediastinal shift also carries a worse prognosis again
related to the volume
of the abdominal contents herniated up in the chest
and comparing right and left diaphragmatic hernias.
The right diaphragmatic hernias have a worse prognosis.

Here's a large left diaphragmatic hernia.
On the still image we can see that the heart is displaced
to the right and filling the left chest is a
heterogeneous lesion with a large cystic collection,
which is the fetal stomach.
Now you'll see that in fact everything is shifted over
to the right and that this is pushing the mediastinum,
not just the heart over to the right.
So if you draw that line through the midline,
you actually pass through contents of the herniated
abdominal contents.

And this is a baby
after birth with a left diaphragmatic hernia.
You can see the endotracheal tube is here
and the nasogastric tube is passed down
through the esophagus
and down into the stomach,
which is then headed up into the chest.
And these are dilated air filled loops
of bowel in the fetal chest in the neonatal chest.

Now this fetus has a left diaphragmatic hernia,
but the stomach is below the diaphragm.
So if you do see a mass
or something, displacing the heart to the right side.
As we do here, look very carefully at what's making up the
content of the left side of the chest.
Look to see if it's abnormal lung or something else.
In this case, we saw tiny peristalsing loops of bowel.
So we knew that this was a left diaphragmatic hernia
because there was bowel herniated up into the chest.
And in this case the stomach stayed below the diaphragm,
but the bowel herniated up.

There have been major advances made in the pediatric
surgery that have allowed
for improved prognosis of fetuses with diaphragmatic hernia.
And one of them is the way that these fetuses are delivered.
We have the opportunity now to intervene on these fetuses
during the course of delivery.
And the way we do this is what's called an EXIT procedure,
which just means ex utero intrapartum treatment,
so a treatment during delivery.
And we also have the option to provide oxygenation,
bypassing the fetal lung with something called ECMO,
which is extracorporeal membrane oxygenation.

With the ability to perform these procedures on
diaphragmatic hernias in the most severe cases,
we can in fact improve the prognosis significantly
for these babies we had this is required
and up to about 20% of diaphragmatic hernias
after birth, the surgeons have gotten better techniques
for controlling and avoiding barotrauma hypoxia
and treating pulmonary hypertension aggressively
and avoiding malnutrition.
And with that, the survival
for these fetuses has improved to almost to about 95%.
In general, the remaining 5% of those
that don't survive often die because of other anomalies
and not because of the lung, the lesions themselves.

So here's a fetus with a very large left diaphragmatic
hernia and this fetus is being delivered by EXIT to ECMO.
I'm actually in the operating room in this case
and I have my transducer on top of the uterus
as the cesarean delivery is begun.
And you can see that I'm watching the fetal thorax
with the heart displaced to the right
and herniated abdominal contents up into the chest.

So this baby now is being delivered by cesarean section
and just the upper part
of the chest is delivered while this baby is placed on ECMO.
And the whole time I'm watching the fetal heart so
that I can give feedback to the surgeons
to tell them how things are going.
In this case, the heart slowed down
to 39 beats per minute
and I alerted the surgeons, I said, they better hurry up.
I was very concerned about this baby. They listened to me.
And here you can see the heart rate has returned to normal
and this baby is now hooked up to ECMO.

Here's another baby that was treated by EXIT to ECMO.
Here's a 35 week scan prior to the delivery.
You can see that the heart is displaced very far to the left
with the right chest filled with abdominal contents.
Here we are now at 37 weeks again showing the heart pushed
far over to the left.
And here we are now in the operating room
where I can monitor the baby as they set this baby up
for ECMO where we can see the catheter,
the internal jugular catheter passed into the right atrium
and the internal carotid artery catheter passed into
the ascending aorta.
And with my ultrasound machine in the operating room,
I can assist them in the positioning
of these devices and catheters.

Sometimes they're masses in the fetal neck
that will obstruct the airway.
These masses can be teratomas, they can be cystic hygromas,
or even an enlarged thyroid.
In all these cases, these masses may obstruct the airway so
that the fetus cannot survive at delivery
unless we intervene in these cases.
And we have been successful in these cases
by doing an EXIT procedure again by working on the baby
as we deliver the baby by cesarean section
to establish an airway and then resuscitate the baby.
We've done this for example with neck teratomas
and I'm going to show you this case.
We will deliver the baby by EXIT procedure
and then do a tracheotomy and resuscitate the baby.

So here's this baby, the fetus
before delivery, we can see a very large neck teratoma.
It's extending to the side of the neck,
but it was also growing into the mouth
and pushing out the tongue.
So this airway was completely obstructed by this teratoma.

Here we are now in the EXIT procedure you can see
that they've delivered the head of the baby and the neck,
but the baby is still connected to the placenta
by its umbilical cord
and the surgeons are working on establishing an airway
with a tracheostomy.
Once the tracheostomy is in place the
with aggressive resuscitation,
they can clear the fluids from the fetal lung.
We can see here there's still a lot
of fluid in the right lung,
but with aggressive resuscitation.
Now we're beginning to see aeration of the fetal lung.
And this baby was then delivered, the teratoma was removed,
and although the tracheostomy tube is still in place,
you can see that the mouth is beginning to return to normal.

This baby had a large neck cystic hygroma at 20 weeks
gestation that continued to grow through the gestation.
Here it is now by 28 weeks and we didn't know whether
or not this was obstruct the airway.
So we did set this baby up for an EXIT procedure.
The baby was delivered part way
and you can see they're attempting
to establish an airway here.
But fortunately for this baby it did not
need a tracheostomy.
The heart rate remained normal
and the lungs filled with air immediately
with their resuscitation
and so the baby could be completely delivered.

Pleural Effusions

Now, besides masses I mentioned there can
be fluid in the chest.
The most common fluid is a pleural effusion.
Overall, the prognosis for a fetus
with a pleural effusion depends on the degree
of pulmonary hypoplasia as well as the underlying cause
of the pleural effusion and whether
or not hydrops is present.
About 12% of cases
with pleural effusions when they're isolated will
have aneuploidy.
And overall the outcome does relate to a variety of things.
About 10% will die in utero.
About 20% will die
after birth in the neonatal period due
to pulmonary hypoplasia or to syndromes such as aneuploidy.
About 30% will survive with continued morbidity
and about 50% will be normal after birth.

So here's a fetus with bilateral pleural effusions.
You can see that when they're pleural effusions,
they surround the lungs
and the lungs collapse towards the mediastinum
as we see here with the lungs just adjacent to the heart.
And here on this longitudinal view,
we see large pleural effusions in each side
with the lungs collapsed, poured towards the mediastinum.

Now we can treat pleural effusions
to help improve the outcome.
For these fetuses, we can do thoracentesis
to drain the fluid and this often reverses hydrops if
it's present, but also allows the lungs to expand
and continue to grow.
If the fluid reaccumulates quickly,
we can put in a thoracoamniotic shunt, which will allow
for continual drainage of the fluid from the chest.
We do these thoracoamniotic shunts
in fetuses who have failed thoracentisis.
We place the pigtail catheter into the pleural space one on
one end and the amniotic cavity in the other
and provide continuous drainage
of the fluid from the chest into the amniotic fluid.
This allows the lungs to expand
and to remain expanded so that they can continue to grow
and don't become hypoplastic.
It also allows for improved blood return to the heart
and so will decrease any hydrops
that may have developed.

So here's a fetus at 24 weeks
with an extremely large left pleural effusion,
pushing the heart way over to the right,
compressing the right lung and the left lung.
We did a thoracentesis of the fetus to drain this fluid.
You can see the needle coming in into the chest.
And here you can see we've completely drained that fluid.
So now the heart has moved over more towards the left side,
but unfortunately the fluid in this fetus reaccumulated very quickly.
Here we see now by 27 weeks,
we have an extremely large left pleural effusion.
The heart has pushed way over to the right
and in addition, we now have accumulation
of ascites in the fetal abdomen.
So the only treatment here now was a thoracoamniotic shunt.
And so that's what we did.
You can see we're passing the trocar
through the maternal abdomen, the uterine wall,
and up to the chest of the fetus on the side
of the pleural effusion.
We then pass that trocar directly into the fluid on the
in the left chest.
And then we advance the catheter into the left chest
and pull back the trocar into the chest wall first and then into the amniotic space
as we see here.
And we have to pull out of this fetus, which
also has skin thickening
until the trocar is left in the amniotic cavity.
When we're all done, you'll see that the shunt is placed
inside the chest on one end
and inside the amniotic cavity on the other.

It took a long time for the fluid from this
large pleural effusion
to drain from the chest into the amniotic fluid, but it did.
And here we can see after the procedure.
Now after waiting a while, we can see
that the catheter's still in place.
It's also in place in the amniotic cavity.
And we notice now that there are actually some fluid on
the right side as well.
So this is directly after the procedure.
When this fetus was born,
there was almost no fluid in the chest.
Here we can see that on the left side of the fetus
that there is almost no fluid on the decubitus view.
We just see a small layer of fluid
and our little catheter stayed in place
for the rest of gestation.
So this fetus did extremely well
and actually went home from the hospital
within a week of delivery.

Conclusion

So there's a lot we can diagnose in the fetus,
prenatally in the fetal thorax,
but there's also a lot we can do
to help improve the prognosis of fetuses
who do have abnormalities in the fetal thorax.
And we do this in order that the fetus can breathe
after birth, not just practice in utero.
Thank you.