Ultrasound Survivor: Congenital Anomalies - SD

Introduction

My name's Dolores Pretorius.

I'm a professor of radiology at the University of California San Diego.

And I'm going to give you a talk called ultrasound survivor on congenital anomalies of fetuses.

My name's Dr. Pretorius.

I'm gonna talk to you about this little talk I made called ultrasound survivor congenital anomalies.

And basically it's a little talk that I've made for you to kind of look at two pictures and see if one of them's better than the other and whether you'd like to be that one based on all these reality television shows.

And this is a picture of me going body surfing in a wave.

And it's one of the things that you've gotta balance your life and it's something I've learned about only in the last couple years and I just wanted to share that with you.

Kidney Anomalies Case

Okay, so this is a picture and I want you as the audience, whoever's watching this anywhere in the world on Sona World to first look at it and think, would I rather be A or would I rather be B?

And these are both anomalies of the fetus and the kidneys.

So just look at it for a second.

Think about what you might wish to be, whether you were A or B, think of the possible differential and then I'm gonna tell you which is which.

Okay, so the first thing you notice is that the one on the left A has multiple cystic components that do not connect, that are peripheral with increased echogenicity in between.

That is classic picture for a multicystic dysplastic kidney.

The one kidney on the other side has just a little tiny bit of dilatation, more normal looking.

The patient in B has large echogenic kidneys.

And I think they measured six centimeters, wasn't it six, about six and a half and five and a half centimeters.

And that is large for any time in gestation because a normal fetus should have kidneys that measure four to five centimeters at term.

So these are large and echogenic and fairly classic for infantile polycystic kidney disease or autosomal dominant.

So let me just tell you one or two things about multicystic dysplastic kidneys.

First off, they do not function. They won't work at all.

They generally involute over time.

And the important thing to realize is that 40% of them have associated renal disease on the other kidney.

They can have a ureterocele from like a duplicated kidney.

They can have another multicystic dysplastic kidney, but if they have that, it'll be fatal because they don't function.

Renal agenesis, if they don't have a kidney on the other side, then it's gonna be fatal because they won't have any renal function.

And then lastly, reflux.

So perhaps this baby might have reflux, just a little tiny bit of dilatation.

So that'll be watched. Most of these kids generally do well, so you would rather be A than B.

Now B was autosomal recessive, polycystic kidney disease.

And these are large echogenic kidneys.

These are large echogenic kidneys that the babies end up with portal hypertension and often end up with liver transplants.

30% of them are affected, and they end up dying as neonates.

50% of them will end up with end stage renal disease or renal transplants in the first decade of life.

And the appearance for autosomal dominant PKD is similar.

So you always wanna look at the mother's kidneys or dad's kidneys if you have him there as well to see if he has, if they have polycystic kidney disease.

Brain Anomalies Case

Okay, here's the next case.

Would you rather be fetus A or fetus B?

We can see that the fetus in A has a monoventricle in the head with fused thalami and this is very worrisome for a holoprosencephaly the fetus and B has mildly dilated ventricles so that these look like they're about 12 millimeter ventricles.

And this is a case of ventriculomegaly or hydrocephalus.

I guess maybe you wouldn't wanna be either one, but probably most people would say B holoprosencephaly.

Holoprosencephaly is a spectrum of disorders going from alobar, semilobar and lobar.

They generally have monoventricles fused thalami, they often have facial anomalies.

Hypotelorism cyclops meaning one eye, schizencephaly, which is a fleshy mass above the region of the eye.

That looks kind of like a nose but it's not a nose.

And they often have midline cleft lip and palate.

Anytime you see a fetus with possible holoprosencephaly, you should think trisomy 13.

Trisomy 13 has polydactyly.

So you wanna go look at their hands and see if you can count the digits or whether they're clenched and you can't even count them.

They can have large cystic kidneys that are usually echogenic.

They have micrognathia and congenital heart disease.

Now the other fetus wasn't so simple, it had dilated ventricles but they were teardrop.

And on this MRI, you can see it a little bit better, but it was on the ultrasound image, the teardrop parallel shape of the ventricles with elevation of the third ventricle in between.

And this appearance of the teardrop is called colpocephaly with dilatation of the occipital horns and the frontal horns have this trident horn appearance.

And that is classic for a Chiari malformation.

So let me go back and just show you the teardrops here on the original picture, that teardrop parallel picture of the ventricles, that's usually the one thing that we can pick up.

Trick Case: Head vs Chest with Pleural Effusions

Okay, this is another case, this is a trick case.

So I just want you to look at it for a couple minutes.

This stumps most people that look at it.

So I think first thing you notice is that the baby on B, that this looks like a cranium with normal choroid.

And indeed this is a normal fetus, so you would rather be B fetus.

A is not the head at all, it's the chest.

And this baby has bilateral pleural effusions with the spine over here to the left.

Now how do you tell the difference?

A cranium has calcification all the way around and abdomen or a chest has a spine in the middle if it's transverse, but it doesn't go all the way around.

So these are probably bits and pieces of the ribs and these are the lungs and the heart is right here in the middle.

So when what do you do when you think about pleural effusions?

You think hydrops, maybe this fetus has congenital lymphedema with a cystic hygroma.

So let's go upstairs and look and see if there's a cystic hygroma in the neck.

Anytime you see pleural effusions, you should look and see if there's skin thickening for hydrops, pericardial effusion, ascites or other markers or anomalies of aneuploidy.

Head Anomalies Case: Encephalocele vs Cystic Hygroma

Okay, the next one, would you rather be A with this fetal head or B with this fetal head?

A is an encephalocele with a mass off the posterior part of the head, and B is a multiseptated mass from cystic hygroma and Turner syndrome.

So what do I want you to know about encephalocele?

I want you to know that patients are often referred because of an elevated AFP maternal serum, AFP alpha-fetoprotein that 75% of encephaloceles are in the occipital region in Caucasians and 75% are frontal in Southeast Asian women.

So we wanna always look both anteriorly and posteriorly.

And if you take folate prior to conception for future pregnancies, you'll have a risk that is the same as the general population for neural tube defects.

Now a cystic hygroma, what do I want you to know about that?

Cystic hygromas are associated with aneuploidy or abnormal chromosomes in 50%, particularly Turner syndrome as in this fetus which is 45 XO and trisomy 21.

These are often fatal.

But this fetus actually survived, which is kind of unusual.

And basically if you see the cystic hygromas in the first trimester, they're more likely to be trisomy 21 in the second trimester.

They're more likely to be Turner's, but they're both common.

Trick Case: Encephalocele vs Fibroid

Okay? This is another trick case.

So you look at the picture on the left and then look at the one on the right.

So the one on the left is an encephalocele with a mass behind it at the occipital region.

So perhaps she was Caucasian.

And then the one on the right is the uterus right here and the bladder with a big huge fibroid in the LUS.

So you would rather have a fibroid.

This is the encephalocele on this baby, you can see that it is occipital.

Femur Anomalies Case: Osteogenesis Imperfecta vs Short Femur in Trisomy 21

Okay, here's another case.

Which femur would you rather have A or B?

A has an irregularity to this femur.

It's not very sharp, it's kind of wrinkled.

B, the femur looks normal.

But when you look at the parameters here, the BPD is at 21 and six weeks and the femur is at 20.

So it's almost two weeks behind.

So basically a short femur.

So fetus A is osteogenesis imperfecta, which is a fatal abnormality in this fetus.

And fetal B has a short femur from Trisomy 21.

So let me just tell you what I'd like you to remember about osteogenesis imperfecta.

I'd like you to remember that they're short, irregular bones, that they have a wrinkled appearance, that there's asymmetrical shortening of the limbs.

So you might not get the exact same on the right versus left because they're related to all those mini fractures that the ribs are often flared.

See how they flare out and that the thorax is small, the heart is a little too big for the size of this.

If you can get pictures of the ribs, you may see the beadedness to them, but most often from 2D, this is the type of picture we get.

You can see the narrowing of the chest here as well.

That's the thorax.

And this is the belly which is a little more prominent.

Now another really important finding for osteogenesis imperfecta is that the cranium is not well ossified.

So it's easily compressible when you push on with your transducer, it deforms the brain and then it pops right back up.

And the other thing is that the brain is very well visualized as you look at it, it feels like you're almost looking at an MRI.

It's 'cause there's not much cranium around it. Okay?

On the other hand, what do you do when you have a short femur?

You go looking for other markers of trisomy 21.

You look for a short femur, a short humerus, an absent nasal bone, echogenic bowel nuchal thickening greater than six millimeters, an echogenic focus in the heart.

And pyelectasis, which is just a little bit of renal dilatation, which has to be greater than four millimeters to be an aneuploidy risk factor.

Now how do you do this looking for short femurs?

We use this table from Nyberg et al and we look at the BPD and this is a normal predicted humeral length.

And if the length is less than 2.18 at four BPD, then that is a short humerus.

Here's a normal femur and if it's less than this number then it's a short one.

Okay? Now what are the anomalies you should think about for trisomy 21 or down syndrome?

First you should think heart disease.

Do they have an AV canal? Atrioventricular canal?

Do they have a septal defect, either an atrial septal defect or a ventricular septal defect?

Perhaps they have tetralogy of Fallot.

All things that we can look for on ultrasound, do they have duodenal atresia with a double bubble sign?

Esophageal atresia with polyhydramnios, mild ventriculomegaly cleft lip and palate unilateral pleural effusion.

Ectopic Pregnancy and Uterine Anomalies Case

Okay, the next case, this is a patient that it's not an anomaly, but she comes into the ER with bleeding rule out ectopic pregnancy.

This is a 3D picture, showing the coronal through the uterus and then where they've taken it from a transverse view.

And then here is the multiplanar picture of a C plane through the uterus with this abnormality right here.

Okay, so box A is an interstitial ectopic and B is a normal.

It just looks like this gestational sac is way out into the myometrium.

So let me show you first thing about ectopic pregnancies is that we have to differentiate whether we really have an ectopic or whether we just have a uterine malformation, like a septate uterus that then has a sac in one horn.

Notice where the interstitial ectopics lie right here.

And those are fairly rare.

Most ectopics are going to be in the tubes someplace.

The unusual places for ectopics to think about today are in the cornua of one of those horns of a bicornuate septate uterus in the interstitium right here at the cornual level or down in the cervix, or the C-section scar right in the cervix as well.

And we can use 3D to help us do that.

So here we have an interstitial ectopic, the first one A with the normal endometrium right here.

And here's this ectopic out to the wall and you can see that on this C plane as well that it's going all the way out to the myometrium.

The interstitial line is helpful from the endometrium over to the ectopic.

And here you can see this line in this patient.

That was five weeks, four days.

Now the interstitial line has been written by a couple different authors and it appears to be highly specific and highly sensitive and we're hopefully looking at that little interstitial portion of the tube.

Now this was the patient in B and notice here on this transverse view that there is some myometrium here.

So we always wanna go back to our 2D images when we're looking at 3D pictures 'cause I think this is very misleading.

We thought this was gonna be an interstitial ectopic when we scanned it, but these pictures made us wonder whether there wasn't just too much myometrium and that it might be normal.

So what do you do? You bring her back.

This is a patient who was brought back four days later.

And notice now that you take this picture of the endometrium and that sac is definitely inside.

It's not abnormal, it's not out here in that interstitial portion of the uterus.

And if you take a rendered image of it, it now looks much more normal than it did on the first plane.

So we just, it's sometimes not easy to figure that out.

Now here are two different women that have uterine anomalies.

Which would you rather be?

So the woman in A has a septate uterus with a gestational sac sitting out here in the horn at five weeks and the woman in B has an arcuate uterus with dipping down just a little bit here, on this patient who happens to be 13 weeks.

So most of us would rather be the arcuate.

And let me tell you why this patient first presented in A with bleeding at six weeks and I just show you a normal endometrium just for you to realize what it looks like in comparison to this patient that has this big septum coming down the middle of it.

She actually went on and did fine, ended up delivering at about 32 weeks gestational age.

Which is not uncommon that these patients with uterine anomalies deliver early because the fetus just is ready to come out before.

But she ended up with postpartum bleeding and she had this large mass of echogenic tissue and when she came in I knew immediately that we needed a sagittal plane through her uterus to see the other picture and see whether there was anything in it.

And retained placenta are very common in patients with septate uterus.

This patient actually had a manual exploration to get the placenta out at her delivery at 32 weeks.

But still she ended up with retained placenta.

Here's another patient with an arcuate uterus with a gestational sac that's at about six weeks.

But I didn't know if you'd even be able to tell she was pregnant.

That's that normal for comparison.

Now there are multiple different uterine malformations and most women are asymptomatic and they occur in about three percent of the population.

By far the septate uterus is the most common.

So when you see a uterine anomaly, that should be the one you're thinking about.

The bicornuate, the didelphys much less common.

And this is the American Fertility Society's classification of uterine malformations.

And I don't think it's important to memorize this per se.

I think it's really important to realize there's lots of variations of how the uterus forms and these can, any one of these could be important for a patient who comes in with bleeding.

She could have something in this horn as well as the main horn that you're seeing or whatever.

So I think it is worthwhile and we do go back to this chart on a routine basis when we're reading out cases.

Now why do we care? It ends up that these were patients that came for ovarian screening for other reasons not related to pregnancy.

First trimester losses are more common in our subseptate uterus than in our arcuate uterus here.

And you can see that we have first trimester losses in up to 42% of septate in contrast to the normal population, which is 12%.

Second trimester losses are more common in the arcuate ones.

And then look at our preterm labor, more common in the arcuate, but still almost twice as many in our subseptate as in the patient that we discussed.

In this case who delivered at 32 weeks.

First Trimester Head Case: Rhombencephalon vs Holoprosencephaly

Okay, which fetal head would you rather be A or B?

A is, here's another patient with a same finding cystic area and A is a normal rhombencephalon and B is holoprosencephaly at 12 weeks.

Here's another picture of that cystic collection in the head, which is a totally normal structure at eight weeks.

So here's holoprosencephaly and it should like this normal butterfly appearance to the choroid.

In contrast, this is holo.

Okay, I've already talked to you about holoprosencephaly.

So we're gonna move on. This is a nuchal translucency screen.

Nuchal Translucency Screening Case

Would you rather be A which has a nuchal translucency of 3.1 or B 4.7.

Now I think most people would say they would rather be A than B, but it ends up that fetus A ended up with a hypoplastic right heart and fetus B ended up being normal.

Now we do know that if you have an increased nuchal translucency that you have an increased incidence of heart disease and in this patient you can see the left ventricle but the right ventricle doesn't have any flow in it whatsoever.

Now let me just tell you a little tiny bit about nuchal translucency screening.

Basically we started doing this because some investigators in England figured out that if you added maternal age with NT thickness and serum analysis looking at HCG and PAPP-A, that we could pick up up to 87 or almost 90% now of trisomy 21s with only a 5% false positive rate.

So they looked for abnormal karyotypes in patients with increased nuchal translucency and this is a large study, 96,000 singleton pregnancies.

They ended up with 651 abnormal karyotypes and 50% of those are trisomy 21, 25% were trisomy 18 or 13 and 10% were Turner syndrome.

5% were triploidy and 10% were other chromosomal abnormalities.

So that is really what we're trying to look for.

But fetuses with an increased NT and normal chromosomes still have an increased incidence of anomalies of about 7%.

And I've just put this if you wanna know what they are, you can go and look at this paper in the American College of OBGYN.

But I've circled here cardiac because that is one of the ones that we are really screening for.

After we find this, how do we counsel patients with an increased NT if they have an increased NT of these of different amounts we look across.

And so if she came in with a 3.7, we would say she has a 21% chance of chromosome anomalies, 3% chance of death, 10% of major anomalies and a 70% chance of being alive and well after delivery.

In contrast, if she has a 6.5 millimeter neck, she will be up at 65% chromosomal and defects 19% death 46% major anomalies and 15% alive and well on the other hand, if you have a NT, it's elevated in the first trimester, you don't find anything, no chromosomal anomaly and they come back and they have a normal fetal heart and a normal ultrasound exam in the second trimester, 95% of those babies are gonna be normal.

Nasal Bone in Screening Case

Okay, would you rather be fetus in A or B?

And these are looking at the region of the nasal bone on fetuses that are being scanned for NT translucency screening.

Well it ends up that A has an absent nasal bone or delayed ossification.

It's not really that there's no nose, it's just that it's delayed and B has a normal nasal bone.

So look at this region, this is just the skin that is not the nasal bone.

This is the nasal bone behind the skin and notice that there's a normal tip at the end.

So for this just changes the screening results significantly.

This patient was 35 years old.

She had a NT of 2.6 which is within normal limits.

She if we call the nasal bone present, her risk is one in 263.

If it's called indeterminate, her risk is one in 125 and if it's absent we get a risk of one in greater than five.

This patient, it was missed on, she returned at 16 weeks and absent nasal bone was found, she had an amniocentesis and she had trisomy 21.

Now what can I tell you?

The nasal bone should look like an equal sign.

Notice the nasal bone in contrast to the skin it should have a number equal sign plus an echo at the tip of the nose.

Ultrasound Safety: MI and TI in First Trimester

Okay? These are also two first trimester nuchal translucency fetuses.

And what I'm trying to show you here is look at the MI and TI on these images and I have blown them up right here for you to be able to see exactly what they are if you can't read them.

But basically fetus A has a TI of 0.2 and an MI of 1.2 and fetus B has 1.1 and 3.4.

So what do you think?

The bottom line is that the MI and TI are output display standards that tell us about the power levels.

The TI is the thermal index, the MI is mechanical index and the MI indicates the potential for ultrasound to induce inertial cavitation in tissues and the TI expresses the potential for a rise in temperature at the ultrasound beam's focal point.

Why do we care? There are concerns for autism for abnormal hearing vision or language development for intrauterine growth retardation for childhood cancer and for increased in non right handedness.

Now there was a study by Angell from Yale where they looked at 335 mice and they used ultrasound for anywhere from 30 to 420 minutes and a small number of neurons failed to acquire their proper position.

They remained scattered within inappropriate cortical layers and the authors thought that this could have consequences related to epilepsy, schizophrenia, and autism.

We do know that lung hemorrhages in young mice and neonatal pigs occur with ultrasound and intestinal hemorrhages also occur in adult mice and that bleeding near the developing bone in young mice occurs.

So we try not to use power doppler in the first trimester unless there's a really good medical indicated reason, approximately 250 million fetal ultrasound exams are performed each year in the United States and to date no adverse effects on fetuses have been reported.

Ultrasound exposure can produce bio effects at diagnostic levels in laboratory studies and valid experimental studies are difficult to perform.

So we leave you with caution advising us to use the ALARA principle which we use for radiation, which is as low as reasonably achievable.

So we do not use color or power doppler in the first trimester unless it's absolutely necessary and we try to keep our MI and TI below one if we can for as long as of the study.

First Trimester Abdomen Case: Gastroschisis vs Physiologic Herniation

Okay, which one would you rather? A or B?

These are both first trimester fetuses from 10 to 12 weeks kind of lookalikes.

A turns out to have a gastroschisis and B turns out to be physiologic herniation, which is totally normal.

So this is the normal bowel that goes out and back in during development.

This is bowel that looks sort of finger-like projections.

Cauliflower like that is not normal.

So the patient in B had these pictures of this physiologic herniation at 10 weeks and two days and this is the cord coming in to the embryo here with color doppler.

We have the fetus and then here's the bowel herniation and there's the cord going in.

When we brought this patient back at 12 weeks, you can see that it's back inside like it's supposed to be.

So that's a totally normal finding in contrast to the fetus with gastroschisis that has this multiple finger-like projections.

And when she came back at 19 weeks you can see these bowel loops outside and that's the normal cord insertion into the belly of this fetus.

Dale Cyr was a sonographer at the chief at the University of Washington for many years and he noticed this and actually wrote this paper and I love showing this picture of the bowel herniation going out here and it should be back in by the end of the 11th week.

Lung Anomalies Case: Cystic Adenomatoid Malformation vs CHAOS

Would you rather be A or B?

A is a cystic adenomatoid malformation and B is CHAOS, which is congenital high airway obstructive syndrome.

And this happens when you have an obstruction at the larynx or the pharynx.

So notice that this lung is too echogenic in comparison to the other side and that the heart is pushed over.

Notice that this fetus has bilaterally echogenic lungs with a very small fetal heart in the middle.

And there's actually two bright black areas here that's called the bow tie appearance because it's the bronchi filled with fluid and this is a normal chest for comparison.

Now the first fetus in A has this large echogenic mass that when you turn on it you see that it's in the lower portion of the lung and that is something that we went on and did MRI in this case.

Here you can see the mass with abnormal signal here suggesting collapsed either CAM or sequestration.

And here you can see it in this coronal view and these are the normal lungs on either side.

These are T2 images where the fluid is bright and this is the chest x-ray on this fetus after birth.

And actually now it's a neonate and you can see the chest, the heart here and there's really very little on the x-ray to see here.

You can see just a little bit of a stranding, very subtle findings for this patient with a cystic adenomatoid malformation.

Now we do CTs or MRIs to look at these to see the vessel.

Today we'd probably do an MR if we had the opportunity because of a radiation dose.

But the truth is we used to operate on all these so these kids wouldn't get infections.

But now our surgeons are being more conservative and they're watching them and unless they get multiple infections, they're not operating anymore.

That's in contrast to CHAOS.

The congenital high airway obstructive syndrome where we see large echogenic lungs that are everting the diaphragm, pushing it down like balloons so that when you look in cross transection through the axial picture with the spine over here, probably be a route at this level right there.

They look almost like large echogenic kidneys, but they're really the lungs pushing down into the belly.

And you can say that this fetus also has ascites as well.

And that once again that heart is very, very small and that's a pretty classic appearance for CHAOS.

Heart Anomalies Case: Normal vs AV Canal

Okay, these are four chamber heart views and I'm going to take B and rotate it for you.

So it's an about the same orientation.

So A turns out to be normal and B turns out to have an AV canal.

And the main finding here is that the AV canal is a single valve that is at the same level where is in a normal four chamber heart.

There's an offset between the two valves, the tricuspid valve and the mitral valve.

This is the left atrium, left ventricle, right ventricle, right atrium spine's back here.

So the normal four chamber view has that normal offset of the apex.

And you can see here the valve is just a little bit inferior to this side and that's very important in identifying the four chamber.

So this patient was a 37-year-old with a positive trisomy 21 risk of one in 22.

And she had an ultrasound at 20 weeks and at 28 weeks that were called normal.

And at 34 weeks she came back and an AV canal was identified and she ended up with trisomy 21.

And let me tell you what, go back and look at these pictures.

It's not so obvious.

The only real finding is that we could see no offset on this valve when we put on color.

That didn't help us. Usually you would think there'd be a lot of color in the middle of the heart.

We didn't see it clearly on this 28 week scan.

It is a single valve, it looks like a single valve going across, and that there's probably a defect here and here, but the coronary sinus lives right behind here and sometimes I've over called AV canals when it's really the coronary sinus.

I can a case here.

You don't see what we expected to see and on our LVOT you often will see your VSDs, but you do not see it in this patient.

It looked normal. When she came back at 34 weeks.

You can see this hole in the middle of the heart and indeed that is an AV canal.

Final Trick Case: Same Fetus Different Views

So this is the final picture.

Would you rather be fetus A or fetus B?

This is a trick because this is the same fetus.

I think the fetus in A looks like a conventional little fetus.

In fetal position, his little hands up here, little feet here.

But in fetus B, in the picture, I think it looks like an old man that looks like he's trying to take a leak and go to the bathroom.

Thank you very much.