0:02

Hello, and welcome to Noon Conferences hosted by MRI Online.

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In response to the changes happening around the world

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right now, in the shutting down of in-person

0:09

events, we have decided to provide free daily

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noon conferences to all radiologists worldwide.

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Today, we're joined by Dr. Katie Davis.

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She's an assistant professor, women's imager, and

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Associate Program Director, Imaging Fellowship

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at Vanderbilt University Medical Center.

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She completed residency at CWRU and fellowship at UPMC.

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Her interests include leadership, mentoring, and education.

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Reminder that there will be time at the

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end of this hour for a Q&A session.

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Please use the Q&A feature to ask all of your questions,

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and we'll get to as many as we can before our time is up.

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We'll also be using the polling feature

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today, so be on the lookout for that.

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A reminder that this window can be moved

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around your screen if it is blocking an image.

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That being said, thanks so much

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for joining us today, Dr. Davis.

0:48

I'll let you take it from here.

0:50

Thank you, Ashley.

0:51

So, uh, good afternoon, everyone.

0:54

Uh, as Ashley said, I'm an assistant professor at

0:56

Vanderbilt University Medical Center, and I originally

1:01

created this lecture for the radiology residents who

1:04

will be taking one of their exams, the core exam.

1:08

And so, um, that will be reflected in this lecture.

1:13

So let's get started.

1:15

There's a lot of material to come to go through.

1:19

All right, so, um, the outline here is shown.

1:24

We are going to discuss, uh, we're basically going to touch

1:27

on, neither one, none of these topics in great depth, but

1:31

touch on the normal transvaginal first-trimester ultrasound

1:35

findings, the location of pregnancy, dating, multiple

1:41

gestations, diagnosis of failed intrauterine pregnancy,

1:45

and evaluation of fetal anatomy in the first trimester.

1:48

And then the second half of the lecture

1:50

will be cases to enforce and enhance the

1:54

learned concepts in this presentation.

2:00

So first, we're going to step through the normal

2:03

transvaginal first-trimester ultrasound

2:05

findings, what you should normally see and when.

2:10

And so approximately one week after the fertilization

2:14

occurs, the blastocyst is going to implant in

2:17

the decidua, and that's what this video is showing

2:21

decidualization begins in the stromal cells

2:23

around the implanted blastocyst, and they spread to

2:26

involve the rest of the pregnancy endometrium.

2:29

The decidua is comprised of the decidua

2:31

basalis, capsularis, and parietalis.

2:35

And out of the three, the decidua

2:37

basalis is the most important.

2:39

Forming the endometrium immediately beneath the

2:42

implantation site and eventually comprising the placenta.

2:47

The placenta is routinely imaged during pregnancy for

2:50

abnormalities, uh, for which I won't cover in today's

2:53

lecture, as it is better seen in the second trimester.

2:57

So then at approximately five weeks, you're going

3:00

to start seeing a gestational sac, and it's a fluid

3:04

collection located in the central echogenic decidua.

3:08

So this arrow is pointing to the gestational

3:11

sac, and the arrowhead is located, is showing you

3:15

the echogenic decidua around the gestational sac.

3:21

Then by five and a half weeks, the first

3:24

thing that you're going to see is the yolk sac.

3:26

So within this gestational sac,

3:28

you're going to see the yolk sac.

3:30

The purpose of the yolk sac is to provide the embryo

3:33

with stem cells, nutrients, and gas exchange, and

3:36

this becomes undetectable, uh, around 14 to 20 weeks,

3:41

sonographically.

3:43

And then by six weeks, you're going to see inside this

3:46

gestational sac is the yolk sac and a tiny embryo with a

3:50

flickering motion, which is going to be the beating heart.

3:57

So at seven weeks, the amnion

4:00

becomes visible around the embryo.

4:02

So this arrow is pointing to the embryo,

4:05

and the arrowheads are pointed to the amnion.

4:08

The star asterisk is showing you the

4:10

amniotic fluid, and that this is the yolk sac.

4:13

So the amnion is metabolically active.

4:16

It's a membrane that's involved in solute and

4:18

water maintenance, and it contains the embryo

4:21

in the fetus, um, with the amniotic fluid.

4:24

And it's a protective space, which

4:25

provides the fetus room to grow.

4:28

And at 10 weeks, zero days, the embryo becomes a fetus.

4:32

So that's what this image is showing.

4:36

So that's what we normally see in

4:38

a normal intrauterine pregnancy.

4:40

So now we're going to talk about

4:42

where is the pregnancy located.

4:46

A normal intrauterine pregnancy.

4:48

The pregnancy is going to be located in the uterus.

4:50

That's easy.

4:51

We don't need to worry about that pregnancy.

4:53

But then we have some other variables that can occur

4:57

that you may see in an emergent situation or even, um, a

5:01

patient getting imaged coming out of, um, from their OB.

5:05

So those options include pregnancy of unknown location,

5:08

which we'll discuss, intrauterine fluid collection.

5:12

So something in the uterus, but nothing in either

5:15

adnexa when you scan bilaterally, or nothing in

5:19

the uterus and a complex or solid adnexal mass.

5:24

So first, we're going to talk about

5:25

pregnancy of unknown location.

5:27

This is really a descriptor.

5:29

So when you're talking about pregnancy of unknown

5:31

location, you're really thinking of a, uh, differential.

5:36

The differential includes an early intrauterine

5:38

pregnancy, so before five weeks, we're not going to

5:41

be able to see the gestational sac or any features

5:44

in the uterus yet; a failed intrauterine pregnancy.

5:48

So the patient had an intrauterine pregnancy, and

5:52

they have miscarried, or an ectopic pregnancy, so

5:56

maybe a fluid collection in the uterus or nothing in

5:58

the uterus and a complex, solid mass in the adnexa.

6:01

And the clinical scenario is that you're going to have a

6:03

positive beta hCG, um, but your ultrasound doesn't show

6:08

you either anything in the uterus or in either adnexa.

6:13

And there's two concepts when talking about pregnancy

6:15

of unknown location that I'd like to hit on.

6:18

You don't want to rely on a discriminatory beta hCG level.

6:23

And you don't want to rely on a single

6:25

beta hCG level in this situation.

6:27

So when you don't see anything in the uterus

6:29

or the adnexa, those are the two points, and I'm

6:33

going to discuss those a little bit in further

6:34

detail to give you some history behind them.

6:37

So discriminatory beta hCG was defined

6:40

as the hCG measurement above which a

6:42

gestational sac is consistently visible.

6:45

On ultrasound, clinicians would compare the

6:48

beta hCG level and the ultrasound findings.

6:52

And if we reported a pregnancy of unknown location,

6:54

the clinician would treat for an ectopic pregnancy.

6:58

So that discriminatory level started around

7:01

1,000 to 2,000 in the mid-eighties.

7:04

But since that time, even in beta hCG values above 2,000

7:08

or even 3,000, in some cases, in conjunction with the

7:12

sonogram demonstrating no intrauterine sac-like structure

7:16

does not fully exclude a normal intrauterine pregnancy.

7:21

So a single beta hCG level.

7:24

So a single beta hCG measurement in a woman with a pregnancy

7:27

of unknown location does not reliably distinguish a normal

7:31

IUP, um, from a failed pregnancy or ectopic pregnancy.

7:36

And what you really want to be doing is

7:37

trending the beta hCGs over 48 hours.

7:41

And the bottom line here is if you're thinking that

7:44

you have a pregnancy of unknown location, it's not

7:47

going to harm the patient to delay treatment by a few

7:50

days, particularly if the clinician is concerned for

7:53

ectopic and the patient is hemodynamically stable.

7:56

You don't want to try to treat either an early intrauterine

8:01

pregnancy or a miscarriage unnecessarily with methotrexate.

8:08

So the beta hCG ratio, as we discussed, the clinicians

8:12

will probably do this, but it is defined as your 48-hour

8:16

beta hCG divided by the initial hour beta hCG.

8:21

So you can see a likely failed pregnancy.

8:24

The ratio is less than, uh, 0.87, and

8:29

this is not doubling appropriately.

8:31

So normal pregnancy is going to double every, um, day.

8:35

So then you're going to have, you're in a

8:37

likely ectopic, you're going to see a beta

8:39

hCG ratio between about 0.9 and 1.7.

8:42

So it's rising, but it's not doubling appropriately.

8:46

And then your beta hCG ratio greater than 1.6 is

8:52

going to be your likely continuing pregnancy.

8:57

So then when we're, we're still

8:59

talking about pregnancy location here.

9:01

So you have, if you have an intrauterine fluid

9:03

collection, but no adnexal abnormality.

9:06

Your differential is, is this a gestational sac?

9:09

Is this an early intrauterine pregnancy?

9:11

Is it a pseudogestational sac?

9:14

Is it just fluid in the uterus,

9:17

or is it a cyst in the decidua?

9:19

And really the most challenging thing is going to be deciding

9:22

is this a gestational sac or a pseudogestational sac?

9:28

So here are some, uh, images of normal early

9:33

intrauterine pregnancy showing a gestational sac and

9:36

some historical classic signs of what the gestational

9:40

sac will look like in an early intrauterine pregnancy.

9:44

So in this image, um, the gestational

9:47

sac here is surrounded by an

9:51

echogenic ring and an outer echogenic ring.

9:55

And the presence of these two rings surrounding the

9:58

gestational sac is a sign of early intrauterine pregnancy.

10:04

In this image, the gestational sac is eccentrically located

10:08

in the echogenic decidua, and it's anterior to a thin

10:13

white line representing the collapsed uterine cavity.

10:17

And this is the interstitial sign.

10:18

So if you see either of these things, you can

10:20

confirm that this patient has an early intrauterine

10:23

pregnancy, but normally, these signs are

10:26

only seen in about 50% of normal pregnancies.

10:29

So if you don't see them, it doesn't mean that

10:31

it's still not a normal intrauterine pregnancy.

10:36

So just remember that 98% of pregnancies are going to

10:39

be normal intrauterine pregnancies, and only about 2%

10:43

of pregnancies will represent ectopic pregnancies.

10:48

So therefore, the takeaway is if you see any round

10:51

or oval collection in, um, in, you should really

10:56

be thinking about an early intrauterine pregnancy.

10:59

Um, again, you don't want to have a clinician

11:01

administer methotrexate to an early IUP or do a D&C.

11:10

So here's this, um, an intrauterine fluid

11:15

collection, but no adnexal abnormality.

11:18

And this is what a pseudogestational sac would look like.

11:21

So this is an example of a pseudogestational sac.

11:24

It's internal debris that conforms to the

11:27

shape and the location of the uterine cavity.

11:30

So you can see that looks very different

11:32

compared to the last slide where we had a

11:34

nice round, um, hypoechoic fluid collection.

11:39

This is irregular; it has a lot of debris on the inside.

11:45

And then moving on to having a complex or solid adnexal mass.

11:50

So if you have a positive beta hCG, you don't see anything

11:55

in the uterus, and you have a complex or solid adnexal

11:58

mass, you must be thinking about an ectopic pregnancy.

12:01

That's your number one differential.

12:04

And the most important thing is then determining

12:06

if the location of this complex, uh, mass

12:10

is in the ovary or outside of the ovary.

12:14

And the best way to determine that is

12:17

to observe its motion relative to the ovary.

12:21

If it's intraovarian, it's most likely going to

12:23

be the corpus luteal–assisted pregnancy,

12:25

unless you see a heartbeat.

12:27

If it's extraovarian, it's most likely going to be ectopic.

12:31

So what the sonographer will do is that the transvaginal

12:34

probe will be in place, and the sonographer is going to put some

12:39

gentle pressure, pushing on the lower abdomen of the patient.

12:43

And here you're seeing the normal ovary sort of moving

12:47

out of the field of view, and you have this complex,

12:50

solid and cystic mass anterior to the normal ovary.

12:53

And so this is, since the ovary is moving separate

12:57

from this mass, this is an extraovarian mass.

13:01

So in the setting of a positive beta hCG, this

13:03

would be compatible with an ectopic pregnancy.

13:10

Okay, so we've described location of pregnancies,

13:13

and we're going to move forward with dating

13:15

concepts in a normal intrauterine pregnancy.

13:21

So traditionally, determining the first day

13:23

of the last menstrual period is the first

13:25

step in establishing the estimated due date.

13:29

So by convention, the estimated due date is 280 days

13:33

after the first day of the last menstrual period.

13:36

This practice assumes a regular menstrual cycle, does not

13:39

account for an accurate recall of LMP, um, irregularities

13:44

and cycle length or variability in ovulation.

13:48

Five out of 10 women do not know

13:50

their LMP or cannot recall their LMP.

13:52

So if the patient is unsure of her LMP, dating should

13:55

be based on ultrasound examination, and ideally you want

14:00

to have it before, uh, 14 weeks gestation, basically.

14:06

So we always will compare the sonographic measurements

14:12

to the LMP, the estimated LMP, to discuss the EDD.

14:18

And to say whether or not it's discordant or

14:21

concordant, and we'll go into that in the next slide.

14:24

In the setting of, um, assisted reproductive technology

14:28

or in vitro fertilization, uh, the estimated due date

14:32

should be assigned using the date of transfer and the

14:36

age of the embryo, and that's pretty darn accurate.

14:38

So, um, most of the times when our patients,

14:41

our IVF patients come in, their due dates

14:45

are not changed by sonographic measurements.

14:46

If our sonographic measurements are discordant,

14:49

there may be something wrong with the pregnancy.

14:53

Um, mean sac diameter measurements are not

14:56

recommended for estimating the due date.

14:58

So, uh, I see this happen somewhat

15:02

frequently amongst our residents.

15:05

What happens is there's an early IUP or maybe a

15:08

failing IUP, and all they see is the gestational sac.

15:12

And so the sonographer will measure the mean sac diameter

15:16

to give a measurement to determine if it's a failing

15:19

pregnancy, but at the same time, the program automatically

15:22

spits out an EDD. It's inaccurate to date a pregnancy

15:27

without an embryo, so you don't, you don't want to use the

15:30

mean sac diameter measurements, you're just going to end

15:33

up having to follow the patient for viability anyway.

15:36

Um, so if ultrasound dating before 14 weeks of

15:41

gestation differs by more than seven days from

15:44

the last menstrual period, the EDD should be

15:47

changed to correspond to the ultrasound dating.

15:50

If it's before nine weeks gestation, a

15:52

discrepancy of more than five days is an

15:54

appropriate reason for changing the EDD.

15:57

So that's just shown here on this graph.

15:59

So on this table, gestational age, we typically

16:03

want to date the pregnancies before 13 weeks, 6 days.

16:07

So before 14 weeks, the method of

16:09

measurement is always going to be crown–rump length.

16:13

And then if the embryo is less than around seven

16:17

weeks, if your ultrasound is, um, discrepant, if

16:23

there's a discrepancy more than five days between

16:25

the last menstrual period and the sonographic dating,

16:29

then you're going to go with your sonographic dating.

16:32

And if the embryo or fetus is anywhere between nine and 14

16:36

weeks, if that number, what your ultrasound is giving you,

16:40

the ultrasound dating is more than seven days discordant.

16:43

One way or the other, positive or negative to the EDD.

16:46

Based on the LMP, you're going to use the sonographic dating.

16:50

So we're going to work through that in some questions

16:52

to make sure that that concept is understood.

16:56

You do not want to use the mean

16:58

gestational sac diameter to date a pregnancy.

17:03

So how many are in there?

17:04

So multiple gestations.

17:07

So for dizygotic or fraternal twins, two ova are

17:12

fertilized by two sperm, which will create fraternal twins.

17:15

So each child will have their own unique

17:18

genetic makeup, with rare exceptions.

17:20

Dizygotic twins will be dichorionic and diamniotic.

17:24

There's two separate placentas here and here.

17:27

Two separate amniotic sacs.

17:32

So monozygotic or identical twins.

17:35

This becomes a little bit more complicated.

17:37

So the degree to which the monozygotic twins

17:40

share placentas and amnion depends on the

17:44

stage of development at which splitting occurs.

17:47

So one egg fertilized by one sperm.

17:50

If you have cleavage at one to three days,

17:53

you'll end up with dichorionic, two placentas,

17:57

diamniotic, two amniotic sac pregnancy.

18:01

So if cleavage occurs at four to eight days, you'll end up

18:06

with one placenta, so monochorionic, and two amniotic sacs.

18:13

So monochorionic diamniotic pregnancy.

18:17

If cleavage occurs at nine to 12 days, it will be

18:21

a monochorionic monoamniotic pregnancy.

18:28

If cleavage occurs past 13 days,

18:31

the result is conjoined twins.

18:35

So here are some things when we're

18:37

looking at multiples that we think about.

18:40

So as a general rule of thumb, the

18:42

number of gestational sacs will equal the

18:44

number of chorions and the number of yolk sacs.

18:47

Sacs tend to equal the number of

18:49

amnions, but it's not always reliable.

18:52

So if you see a multiple pregnancy,

18:55

and you can see two separate placentas, that's easy.

18:58

It's a dichorionic pregnancy, but then sometimes

19:02

it gets a little bit complicated.

19:03

So this is an example.

19:06

There's two pregnancies, so twin A, twin B, and

19:11

there's the posterior placenta, shown here.

19:15

And what this is showing you is this, quote, lambda sign.

19:19

So this lambda sign represents chorionic tissue

19:21

wedge between layers of intervening membranes,

19:25

so the membrane that separates both of the twins,

19:28

where it meets the fetal surface of the abutting

19:30

placenta, in a dichorionic twin pregnancy.

19:33

So if you see this sign, this is compatible

19:36

with a dichorionic lambda sign.

19:40

The T sign, on the other hand, is when the

19:44

thin membrane forms a perpendicular angle

19:48

when it meets the fetal surface of the shared placenta.

19:52

So there's a single placenta here,

19:55

and this indicates a monochorionic.

19:57

So one placenta, diamniotic, this thin

20:01

membrane showing you two amniotic sacs.

20:05

So monochorionic diamniotic twin pregnancy,

20:10

and usually transvaginal ultrasound is adequate to

20:13

see this intertwin membrane of the two separate

20:16

amnions, but in practice it can be very difficult.

20:21

All right, so we're going to move ahead and talk

20:24

about diagnosis of failed intrauterine pregnancy.

20:29

So this is a journal article from the New

20:31

England Journal of Medicine, um, 2013.

20:34

I always had my residents have this when they're on

20:36

call because this is strict criteria, strict diagnostic

20:41

criteria for diagnosing a failed intrauterine pregnancy.

20:45

So this column, findings diagnostic of pregnancy

20:48

failure, and this column, findings suspicious

20:50

for, but not diagnostic of pregnancy failure.

20:52

And we're going to step through this chart.

20:57

So findings diagnostic of a pregnancy

20:59

failure fall into three categories.

21:02

An embryo of a certain size without a heart

21:04

rate, a gestational sac above a certain size,

21:07

and no embryo or no embryo with a heart

21:10

rate visible after a certain time interval.

21:13

So the size here is key: crown–rump

21:16

length greater than seven millimeters.

21:18

If you see an embryo greater than seven millimeters and

21:20

there's no heart rate, you can call it a failed pregnancy.

21:25

Same here if you have a mean sac diameter,

21:27

gestational sac above 25 millimeters and no embryo.

21:31

You can call this a failed pregnancy.

21:33

And then you have some, um, time intervals.

21:36

So a scan done—

21:38

and the key here is two weeks after an initial

21:41

scan that shows a gestational sac only.

21:44

It does not show an embryo with a heart rate.

21:46

You can call that failed.

21:48

And then if you have an initial scan showing a

21:50

gestational sac and a yolk sac, and then a scan

21:54

done 11 days later that does not show an embryo

21:57

with a heart rate, you can call that failed.

21:59

You don't need a follow-up

22:00

ultrasound for any of these findings.

22:02

You can call it failed, and the

22:04

clinician will take care of that patient.

22:08

So here's a couple of examples.

22:09

So patient A, in this scenario, you

22:12

have a gestational sac with an embryo.

22:15

The embryo does not demonstrate a heart

22:16

rate, and the crown–rump length is greater

22:18

than seven millimeters, at nine millimeters.

22:21

So this is a failed pregnancy.

22:23

In this example, they're measuring the mean sac diameter,

22:27

which is 32 millimeters, greater than 25 millimeters.

22:31

Like we said, that was our strict criteria.

22:32

So we can call this a failed pregnancy.

22:37

And then you have findings suspicious for,

22:39

but not diagnostic of, pregnancy failure.

22:42

Crown–rump length less than seven.

22:45

That's the key.

22:45

The seven is going to be your key here.

22:47

For size, mean sac diameter less than 25.

22:53

And then we have these time intervals again.

22:55

And basically it's the same thing, but they

22:57

haven't waited that two weeks or 11 days later.

23:00

And so you cannot, by strict criteria, call

23:03

this failed, even though, uh, we know the

23:06

outcome is very poor for that pregnancy.

23:09

And then they've added no embryo with the

23:10

heart rate less than six weeks after the LMP.

23:14

This is problematic because, as I already stated,

23:16

the patients have a hard time remembering their LMP,

23:20

especially if they're not trying to get pregnant.

23:22

So for all of these findings, it is

23:26

appropriate to recommend a follow-up sonogram

23:28

in seven to 10 days if the clinician needs it.

23:32

So here are two examples now of those.

23:34

So in this case, you have a gestational sac.

23:37

You have a yolk sac, and you have an embryo, but

23:40

the embryo crown–rump length is only three millimeters.

23:43

So you need to let this pregnancy continue.

23:45

You'll follow this up in the appropriate timeframe and

23:49

see if there's normal progression of the pregnancy,

23:51

if you don't have a prior study to compare.

23:54

Same thing here.

23:55

If you don't have a prior and you have a gestational

23:58

sac, they're giving you the mean sac diameter,

24:00

which is 21, and you don't see an embryo.

24:04

You have to allow this pregnancy to continue before

24:07

you can, by strict criteria, call it a failed pregnancy.

24:13

So here are some other ancillary findings

24:15

that help you think that this is suspicious,

24:18

but not diagnostic for pregnancy failure.

24:21

So in this example, you have amnion adjacent

24:24

to a yolk sac, but you have no visible embryo.

24:27

So we know, as I showed you at the beginning of this lecture,

24:30

the normal sequence of a normal intrauterine pregnancy is to

24:33

see a yolk sac followed by an embryo, followed by an amnion.

24:38

Therefore, to have a yolk sac adjacent

24:40

to an amniotic sac is abnormal.

24:44

The one exception is that this can be mistaken

24:46

as pregnancy failure when it's actually two

24:49

adjacent yolk sacs in the setting of an early

24:53

monochorionic diamniotic twin pregnancy.

24:56

You need to follow up here to exclude that.

25:00

In this scenario, we have an expanded amnion,

25:03

so we know that an embryo without cardiac

25:07

activity, um, with an amnion visible around it.

25:12

It's the, typically the normal progression

25:15

is that the embryo with a heart rate

25:17

is seen before this amnion is formed.

25:20

So to see this expanded amnion visible

25:23

without that heart rate is abnormal.

25:25

So you're going to follow this.

25:28

And then the last one is you have an enlarged

25:31

yolk sac greater than seven millimeters,

25:33

and this one's measuring up to eight.

25:35

And here's the, uh, embryo here.

25:40

So other ancillary findings: slow heart rate.

25:43

So if the gestational age is 6.0 to 6.2 weeks, anything

25:48

less than 90, or if the gestational age is 6.3 to seven

25:53

weeks, less than 110, that would be fetal bradycardia.

25:57

Um, perigestational hemorrhage of at least

26:00

two-thirds of the gestational sac, or a

26:02

volume of greater than 60 millimeters.

26:04

So that crescentic fluid collection is

26:07

showing you the perigestational hemorrhage.

26:09

This patient is a little bit further along.

26:11

You can see the placenta here, and then

26:13

part of the, um, gestational sac in here.

26:17

And then a small gestational sac in relation to the embryo.

26:21

So you can see, here's an enlarged yolk sac.

26:24

Here's the embryo, and they're measuring, they're

26:26

going to measure the mean sac diameter, and they're

26:29

going to subtract it from the crown–rump length.

26:31

And anything less than five millimeters

26:34

is suspicious for pregnancy failure.

26:41

So now we're going to talk about, very briefly,

26:43

evaluating the fetal anatomy in the first trimester.

26:46

So with the advancement of technology, evaluation of

26:50

fetal anatomy, including a detailed fetal cardiac exam,

26:54

is possible in the late first trimester in experienced

26:57

centers, or when educational programs are instituted.

26:59

The reliability and detection rates of first-

27:02

trimester anatomic evaluation have been demonstrated.

27:06

At our institution, we do normal anatomy

27:09

surveys at 18 to 20 weeks.

27:12

Um, but this is just to show you

27:14

how well the technology has come.

27:17

So when we're looking at the head

27:18

and neck, this is, uh, at 12 weeks.

27:21

You can see the thalamus, the medulla, um, uh,

27:25

the midbrain, sorry, the brainstem medulla.

27:29

And then you have the choroid

27:31

plexus of the fourth ventricle.

27:34

And over here you can see that the lateral

27:38

ventricles are filled with this echogenic

27:40

choroid plexus, and they fall right here.

27:43

So these are just normal findings that we see.

27:46

And then you can see that the cranium

27:48

will start to ossify at about nine weeks.

27:50

So that can also be seen.

27:55

Um, head and neck at 12 weeks.

27:57

So the nuchal translucency can be measured.

27:59

Most of our patients are being tested by

28:01

cell-free DNA screening at about 10 weeks, which

28:04

can determine if a woman has a higher chance of

28:06

having a fetus with chromosomal abnormalities.

28:09

Um, but if they can't afford it or their insurance

28:11

doesn't cover it, we certainly measure the nuchal

28:14

translucency, and it's reliably measured between 11 and

28:17

14 weeks, so it should be less than 3.5 millimeters.

28:22

Um, and this is showing it to be normal at 1.2.

28:26

Increased nuchal translucency is a risk factor for aneuploidy.

28:30

And if you do see an abnormal nuchal translucency, it

28:32

has a high prevalence with associated cardiac anomaly.

28:35

So you should be paying attention to the

28:38

cardiovascular system on fetal anatomy

28:40

if you see an abnormal nuchal translucency.

28:43

And in our practice, if we see an abnormal nuchal translucency,

28:46

we do recommend that the patient be further tested with the

28:49

cell-free DNA screening for aneuploidy if the patient desires.

28:56

So evaluation of the fetal chest.

28:58

So these arrows are pointing to the diaphragm.

29:01

This is the stomach underneath the

29:04

diaphragm, and that's what we're looking for.

29:06

We're making sure that the stomach is not above

29:08

the diaphragm and that the diaphragm is intact.

29:11

And then here, this is just a semiclip

29:12

of the four-chamber heart.

29:15

And in this early gestation, we usually can tell the situs.

29:20

So looking at the, um, apex of the

29:23

heart in relation to the stomach.

29:25

The four-chamber heart view, we can see the

29:27

cardiac axis, we can see the outflow tracts.

29:30

However, we routinely will image these at 18 to 20 weeks.

29:33

But this is just to show that you can

29:35

see, um, the abdomen.

29:39

You want to pay attention to the ventral wall.

29:41

So physiologic herniation of the midgut can

29:43

be seen as early as seven weeks and becomes

29:46

most identifiable from nine to 10 weeks.

29:48

So that's normal.

29:50

And then by 12 weeks, the thickening of the

29:52

umbilical cord is resolved, and the umbilical cord

29:55

insertion is normal into the abdominal cavity.

29:59

The genitourinary, it's very difficult to

30:02

see the kidneys in the early first trimester.

30:04

If you do see them, they'll be hyperechoic,

30:07

um, with hypoechoic centers just lateral

30:10

to the spine in the retroperitoneum.

30:12

This is just an image of the

30:15

urinary bladder down in the pelvis.

30:16

It's easily seen; it's an anechoic space, and then the

30:20

color Doppler image demonstrates, um, umbilical

30:23

arteries bifurcating around the fetal bladder.

30:26

So this is a three-vessel cord.

30:28

You have two, um, umbilical arteries,

30:30

and then you'll have the umbilical vein.

30:34

So musculoskeletal, um, the spine is detectable as

30:38

two parallel lines, so here as early as the eighth

30:42

week of pregnancy, and the majority of embryos with the

30:44

cervical, thoracic, and lumbar spine being visualized

30:47

in up to 72% of fetuses between 13 and 14 weeks.

30:50

And by the 10th week, the full length

30:52

of the limbs are, um, able to be imaged.

30:54

You have an arm, and this baby's waving to you.

30:59

Okay, so we're going to transition now to cases.

31:02

And we are doing a polling system.

31:05

So what I'll do is I'll show you the case, and

31:08

then you'll put your answer in; you'll plug

31:10

your answer in, and then we'll review these.

31:14

So first question: what does the yellow

31:17

arrow and the blue arrowhead represent?

31:21

Respectively?

31:24

Okay, so the majority of you said amniotic

31:26

sac and yolk sac, and so the correct answer is—

31:35

Can't get my PowerPoint to advance, Ashley, after that.

31:40

Um, I am not sure.

31:41

I just stopped sharing it, so see if it's working now.

31:49

There we go.

31:50

So the majority of you were correct. So the

31:52

amniotic sac, it's a little bit difficult to see.

31:55

So here, this thin line, I hope it's, um,

31:59

showing on your screen, and then the yolk sac

32:02

here.

32:05

All right, so the majority said early

32:07

intrauterine pregnancy and right corpus luteal cyst.

32:10

Great.

32:11

Um, a percentage of you thought maybe this was a

32:14

right ectopic pregnancy and a pseudogestational sac.

32:17

All right.

32:18

I'm going to close this, and we'll discuss.

32:29

Okay.

32:29

So the correct answer is C. So you have the uterus, and you

32:33

have a small, anechoic structure in the uterus, and then you

32:38

have something in the right adnexa, and they're measuring,

32:42

um, they're measuring the total ovary here.

32:46

So this is a corpus luteal cyst and an early pregnancy.

32:50

So this is not a pseudogestational sac; it's not

32:52

irregular, it's not taking up the uterine cavity.

32:55

And again, I want to remind you that you should

32:58

be thinking, um, giving this the benefit of the doubt.

33:01

Now, I would ideally be giving you a, um, cine clip

33:05

showing you that this was, in fact, in the ovary in this case,

33:08

but this is an early IUP and a right corpus luteal cyst.

33:12

And this is the same patient with a follow-up

33:14

sonogram confirming, here's the intrauterine

33:17

pregnancy advancing at eight weeks, four days, and

33:19

then the right corpus luteal cyst is demonstrated.

33:24

So how about this case?

33:25

So this is a 26-year-old female with a

33:28

positive pregnancy test and left adnexal pain.

33:31

What is the most likely diagnosis?

33:35

All right, how about this case?

33:36

So this one, um, hang on a second, Ashley,

33:39

before you put up the poll, I have to scroll

33:40

back and forth between the two images.

33:42

So this is one of two.

33:44

A 29-year-old female presenting for dating and viability.

33:47

There's a small structure in the uterus and

33:50

showing a fetal heart rate of 95 beats per minute.

33:54

And I'm going to go to the next case.

33:57

So now they're scanning over to the right adnexa,

34:03

and they see this structure.

34:06

What do you guys think about this one?

34:09

Good.

34:10

So about 50% said heterotopic.

34:11

That is correct.

34:12

This is a heterotopic pregnancy.

34:14

I'm going to go back to show.

34:19

So we have an early IUP, has a fetal heart rate.

34:23

It's concerning because it's

34:24

bradycardia; it's 95 beats per minute.

34:27

And then when they scan adnexa, you're seeing a complex,

34:30

um, mass with a yolk sac in the center of it, and you have

34:33

some hemorrhagic free fluid in the posterior cul-de-sac.

34:36

So this is compatible with a heterotopic pregnancy.

34:39

In this scenario, the patient lost,

34:41

um, the intrauterine pregnancy.

34:44

Um, when you have a healthy IUP, they can administer

34:49

potassium chloride or methotrexate into the

34:51

heterotopic pregnancy with a great deal of success,

34:54

with the normal intrauterine pregnancy progressing.

34:56

But in this case, the patient

34:58

unfortunately did not have that luck.

35:01

All right, how about this case, a 36-year-old

35:04

woman presenting for dating and viability?

35:06

What is the most likely diagnosis here?

35:11

Finding suspicious for failed.

35:12

Okay, so here we're going to talk about this.

35:16

Um, so you have a gestational sac with a

35:19

yolk sac, and you have an embryo, and the

35:22

measurement of the embryo is three millimeters.

35:24

So remember, you can't call a failed pregnancy until

35:27

that crown–rump length is over seven millimeters.

35:30

So you're going to recommend, um, you can either recommend

35:32

a follow-up, which we do in our, uh, facility, um,

35:36

and you're not really going to expect to see a heart rate

35:39

yet because this is not dating greater than six weeks.

35:42

So the crown–rump length is 0.27, or three

35:46

millimeters, at five weeks, six days.

35:48

So this is an early IUP.

35:49

You want to give this more time.

35:52

Okay.

35:53

How about this one, a 33-year-old woman

35:55

presenting for dating and viability?

35:58

Her estimated due date by her LMP is December 3rd, and her

36:03

estimated due date by sonographic criteria is December 7th.

36:07

What is the best answer?

36:10

So this is concordant.

36:13

So this is, um, well within the—

36:19

What was it?

36:19

Let's see.

36:20

It's four days.

36:21

So this isn't more or less than plus or minus, um, seven days.

36:26

So this is concordant, and you would go ahead and use

36:28

the patient's last menstrual period as her estimated

36:30

due date for establishing growth later on.

36:36

How about this one?

36:38

So good.

36:39

So discordant, you're going to use the sonographic date.

36:41

So this one is 10 days off.

36:44

So it's, the sonogram is giving you a

36:47

measurement that is 10 days from the LMP.

36:50

So you're going to say it's discordant and use the

36:52

sonographic dating to, to see how this pregnancy goes.

37:01

Okay, moving right along.

37:03

So how about this one, 31-year-old

37:05

presenting for dating and viability?

37:07

What is the most likely diagnosis here?

37:11

All right, let's see how you did.

37:13

Good, good.

37:14

So, dichorionic diamniotic pregnancy.

37:19

So this is nicely showing that lambda sign, and then

37:22

the video was showing you, um, I can get it to play.

37:27

There we go.

37:27

So separated here very nicely, thick intervening membrane.

37:33

Each, uh, embryo is, it's a slam dunk, right?

37:36

Each embryo has their own yolk sac and amniotic sac.

37:43

All right, how about this one?

37:47

Monochorionic diamniotic, good.

37:48

You already got that one, right?

37:50

So, um, make.

37:58

Okay, so one gestational sac.

38:01

Uh, each embryo has their own amniotic sac,

38:05

which are these very thin, I can stop this video.

38:09

I can't stop this video, but very thin sacs

38:11

surrounding each embryo, so that this was monochorionic diamniotic.

38:18

How about this one?

38:22

All right, let's see how you did, mono.

38:24

Mono.

38:25

Good.

38:31

So this is just showing one gestational sac,

38:33

and these, uh, embryos are sharing this one

38:37

single amniotic segment you can see here.

38:43

All right.

38:43

How about this one?

38:47

Let's see how you.

38:51

Only 7% said they need a lifeline.

38:53

So that's encouraging.

38:55

Um, good.

38:56

Most of you got it correct.

39:03

So each one of these has their own,

39:05

is going to have their own placenta.

39:07

Each one has their own yolk sac.

39:08

Each one has their own amniotic sac.

39:10

So it's a triamniotic triplet.

39:18

All right, so hold off, Ashley, on the poll for a second.

39:21

So, 37-year-old female presenting for follow-up viability.

39:24

So her study performed on December 18th is showing

39:28

you a dichorionic diamniotic twin pregnancy.

39:32

So di pregnancy.

39:34

And, um, both of the fetuses are,

39:40

are, I'm sorry, embryos are shown.

39:41

And then you have the current study, which is

39:43

almost three weeks later, shows you a picture of.

39:51

This.

39:51

So measuring a crown-rump length, nine

39:53

weeks, four days, showing a heart rate.

39:56

And then in the second sac you no longer see the embryos.

40:02

So what is this going to be?

40:06

Great.

40:07

So vanishing twin.

40:08

So, uh, loss of one twin can occur at any time

40:11

during the pregnancy, but it is most common

40:14

during the early first trimester, when there is

40:16

loss of one twin in the early first trimester.

40:18

The remaining singleton has a good prognosis,

40:21

and in most cases, the second sac is no

40:23

longer seen later in pregnancy or at birth.

40:26

So that's, that led to us calling

40:28

this phenomenon a vanishing twin.

40:32

All right, how about this case?

40:39

Good, demise of conjoined twins.

40:42

So, um, for this case you have a crown-rump length.

40:47

They're measuring of.

40:49

Uh, almost 19 millimeters, and

40:51

you don't have a fetal heart rate.

40:52

So you can call that a failed

40:54

pregnancy by strict criteria, right?

40:56

'Cause it's greater than seven millimeters.

40:59

And this happens to be conjoined twins.

41:00

So they, um, the most common site of connection

41:05

is going to be the thorax, in about 40%.

41:07

And this one's showing actually the

41:08

connection at the abdomen, which is the

41:11

second most common, at 33% of conjoined twins.

41:22

Okay.

41:23

How about this case?

41:26

All right, let's see how you did.

41:30

Good.

41:30

So failed.

41:31

So by strict criteria, mean sac

41:33

diameter is greater than 25 millimeters.

41:35

We don't see an embryo.

41:36

We can call this failed, and we don't need to follow this up.

41:39

Very good.

41:44

How about this case?

41:47

All right, let's see how you did.

41:51

Failed.

41:52

Good.

41:52

So you can call this failed again because

41:55

the crown-rump length is greater than seven

41:57

millimeters, no fetal heart rate is detected.

41:59

And you also have this sign, um, of an

42:02

enlarged yolk sac at seven millimeters.

42:04

So this is a failed.

42:05

You don't need to follow this.

42:10

How about this case?

42:13

Okay, let's see how you did.

42:18

Good.

42:18

So suspicious for failed.

42:19

Right.

42:20

So we have a crown-rump length that's

42:22

not quite greater than seven millimeters.

42:24

It's measuring six weeks, zero days.

42:26

We don't see a heart rate, which we'd normally see a

42:28

heart rate at six weeks, zero days, but not always.

42:31

And the mean sac diameter is

42:32

not greater than 19 millimeters.

42:34

So we have nothing that by strict

42:35

criteria we can call failed.

42:37

So we're going to go ahead and follow this pregnancy.

42:40

Uh, give it one more chance.

42:42

So this is the same patient.

42:44

Is presenting for a sonogram seven days

42:47

later, which confirms a failed pregnancy.

42:50

So which of the following are false?

42:54

Which out of the following questions

42:56

are false regarding pregnancy failure?

43:00

Good.

43:01

So, um, this statement, the first statement,

43:04

crown-rump length of five, that used to be

43:07

what we would go by, but now we go by seven.

43:11

So this statement is false.

43:13

All the rest are diagnostic of pregnancy failure.

43:19

All right, let's see how you guys did.

43:20

I,

43:25

And so majority of you said holoprosencephalic.

43:28

Um, the actual answer is rhombencephalon.

43:31

So normally, um, seen on transvaginal ultrasound

43:36

around eight to 10 weeks is this hypoechoic.

43:40

Space in the fetal head, and that's normal anatomy.

43:43

It represents the developing medulla,

43:45

pons, cerebellum, and fourth ventricle, and

43:47

collectively is known as the rhombencephalon.

43:53

So how about this case?

43:57

All right, let's see how you did.

44:01

Good.

44:02

So this is an acranium, and by this time in fetal

44:06

development, the cranium should be starting to ossify.

44:09

So we, we should see normal calvarium up here.

44:12

Instead, we see an abnormally shaped

44:14

head and no ossification of the cranium.

44:22

And so this is just showing you, um, the

44:25

patient returns three weeks later, confirming.

44:31

So this is all abnormal configuration of

44:34

the brain without ossification centers.

44:39

So this is a one out of two.

44:40

I'm going to show you these first images.

44:42

So, um, we're focusing on the fetal head and neck here.

44:47

And so take a look here.

44:49

So this is a coronal image.

44:51

This is a sagittal image.

44:53

And then I'm going to go to the next slide in

44:56

a second, give you a chance to look at that.

45:02

And this is a clip of the fetus.

45:06

So again, sort of a coronal cut.

45:09

These are the baby's arms coming up.

45:14

So, which of the following is false?

45:16

Um, the, the false statement is that folic acid does not

45:19

reduce the risk of recurrence in subsequent pregnancies.

45:22

Um, folic acid can reduce the risk of

45:26

recurrence in, in pregnancies, and all

45:28

of these are, uh, true about anencephaly.

45:30

So it results as a failure from

45:33

closure of the anterior neural tube.

45:35

The alpha-fetoprotein will be elevated, and this case

45:39

is nicely showing the frog-eye appearance of a fetus

45:43

that is missing cranial bone, with a portion of the brain,

45:48

sort of free floating in the, um, amniotic fluid here.

45:59

So you can see that brain.

46:09

Okay.

46:09

How about this one?

46:12

So you ha you have a, um, sagittal image here.

46:16

This is the head, and then you have a sort

46:21

of an axial image, an image going through

46:24

the head at the base of this abnormality.

46:29

All right, let's see how you did.

46:35

Good.

46:35

So this was a meningoencephalocele.

46:37

You can see the meninges filled with fluid and part

46:40

portions of the brain, uh, at the base of the neck floating

46:47

here.

46:49

So here, as we go through this video

46:52

and then in the axial projection here,

47:02

Okay, this is a companion case, so this

47:03

is a 20-week fetal anatomy scan, but just

47:06

another nice case to show some neuroanatomy.

47:11

So 36-year-old woman presenting for a 20-week fetal

47:14

anatomy ultrasound. Here is an, uh, axial cut of the

47:17

fetal brain, um, image looking at the cerebellum,

47:22

image with the focus on the lateral ventricle.

47:27

And I'm going to flip to the next slide in just

47:30

a second after you have a moment to look.

47:34

All right.

47:35

Let's see how you did.

47:39

It's a Chiari II.

47:41

So let's go back and look at the images.

47:44

So this image is showing you the scalloping of the frontal

47:49

bones and this classic lemon sign. This image is showing

47:53

you the, I'm sorry, I'm pointing to the wrong screen.

47:56

So lemon sign here.

47:58

This image is showing the, um, abnormal

48:00

shape and small size of the cerebellum.

48:02

So this is the banana sign, obliteration of the

48:06

cisterna magna, and giving resultant ventriculomegaly

48:10

due to leakage of cerebrospinal fluid, um, related to a

48:13

neural tube defect, which we see on the next slide here.

48:18

So you have open, your spine is open. You have the

48:21

neural tube defect here, and that's going to cause

48:24

inferior displacement of the cerebral structures.

48:29

So I was going to go through each explanation of all the

48:33

options, but given that we're already running behind,

48:36

I'm just going to go ahead and get through my cases.

48:39

I'm going to move forward.

48:45

All right.

48:45

How about this case now?

48:50

All right, let's see how you did.

48:53

Good.

48:53

So here's your holoprosencephalic, that

48:55

this is what, um, that would look like.

48:58

So holoprosencephaly is an abnormality of the forebrain

49:01

characterized by, um, incomplete separation of the

49:05

cerebral hemispheres and formation of the diencephalon.

49:08

And there's three varieties.

49:10

Um.

49:13

But on ultrasound, you, there's no, um,

49:16

midline echo anteriorly due to an absent septum

49:19

lucidum, and a single ventricular cavity is shown.

49:23

So that's your holoprosencephaly versus the rhombencephalon, which

49:26

was a normal structure that we see very early in pregnancy.

49:31

How about this?

49:35

So I'm going to start by showing you these images, and

49:37

then I'm going to move forward through the images.

49:48

All right, so what is the most likely diagnosis here?

49:55

All right, let's see how you did. Good.

49:59

951 00:49:59,384 --> 00:50:01,035 So majority got the right answer.

50:01

Cystic hygroma. And your follow-up question is, which

50:07

of the following regarding cystic hygroma is.

50:11

So three of these choices are true, one is false.

50:19

Okay, let's see how you did.

50:23

Correct.

50:24

C is false.

50:25

Septations are very common.

50:27

They should not prompt you to think of infection.

50:33

All right, so next question.

50:36

27-year-old female, 13 weeks, three days, no

50:39

prior studies presenting for dating and viability.

50:42

What is the most likely diagnosis?

50:47

Okay, so the answer here is an omphalocele.

50:50

So you have, um, the sagittal image.

50:53

You have viscera coming protruding

50:56

out of the ventral abdominal wall.

50:57

The umbilical cord is inserting

50:59

directly onto that abnormality there.

51:03

Let me go to the next.

51:06

So here's a nice cine clip.

51:08

You have bowel,

51:10

viscera, and stomach out into this defect.

51:14

And this is the baby, um, chest with beating heart here.

51:19

So, which of the following is false regarding this entity?

51:22

So which of these statements is not true regarding all?

51:30

So D. So up to 75% of cases of omphalocele have

51:34

associated chromosomal and nonchromosomal congenital

51:37

abnormalities, with trisomy 18 being the most common.

51:40

Trisomy 13,

51:41

the second most common.

51:45

Okay, this is a companion case.

51:47

This is a little bit older fetus.

51:50

18 weeks, zero days.

51:52

Young woman presenting for fetal anatomy scan.

51:56

Have two images shown here.

52:02

And the question is, which of the following

52:04

are false regarding this entity?

52:06

So the cine clip is showing, um, bowel protruding

52:11

out into the, through a defect in the ventral wall.

52:16

And on the previous slide, the

52:18

umbilical cord was inserting normally.

52:21

Um, so the correct answer is going to be

52:25

free-floating loops of bowel and viscera.

52:28

So typically viscera does not protrude

52:30

in the setting of usually bowel.

52:37

And I think this is my last case.

52:39

So 24-year-old woman presenting for dating and viability.

52:43

It's an early OB, 12 weeks, zero days.

52:45

What is the correct diagnosis?

52:55

In this case, it's megacystis.

52:58

So megacystis is the most common GU abnormality seen

53:02

on first trimester ultrasound between 10 and 14

53:05

weeks, and around 50% of this, uh, megacystis will

53:10

resolve at the time of her 20-week ultrasound scan.

53:13

So attention on follow-up studies is, is warranted.

53:17

Okay, so we touched on a lot of topics, uh, very

53:20

broad, but I hope that you have a better sense of

53:23

what we normally want to see during a normal early

53:26

intrauterine pregnancy, how you figure out the location

53:30

of the pregnancy, and things to consider how we date

53:34

and the importance of dating and making sure that

53:36

you're concordant with your last menstrual history,

53:38

and when to flip over to using

53:40

the sonographic dating criteria.

53:42

Um, strict diagnosis of failed intrauterine pregnancy, and

53:47

then what anatomy we can see in the early first trimester,

53:51

and associated anomalies associated with that anatomy.

53:55

And hopefully you found some value

53:57

in going through these cases.

53:59

Um, the last slide is my reference slide.

54:01

I had think I have gone over my time, Ashley, is that true?

54:06

We're a little over, but I do see a lot

54:07

of questions in this Q and A feature.

54:09

If you have about 10 minutes, I would

54:10

love to get a few of them answered.

54:12

Yeah, let's see.

54:13

Okay, so I think I'm starting at the very first one.

54:18

So I'm gonna ask some studies say that putting

54:19

color Doppler on first trimester fetus is

54:21

not good because it might lead to anomalies.

54:23

What's your point on that?

54:25

That is true.

54:25

We do not put color Doppler on our fetuses.

54:28

We do, um, we will check for our heart

54:30

rate, but we don't put color Doppler on.

54:31

The only time that we really do that is when we think

54:35

that we have an ectopic pregnancy, and we have next son.

54:37

We'll put color Doppler to get that nice, um, ring of fire

54:41

around the ectopic pregnancy, but we do minimize that.

54:46

Um, how to diagnose heterotopic pregnancy.

54:49

I think we hit on that later on in the lecture.

54:55

I think that this, this question may have been asked

54:57

early on, so I think that we sort of touched on that.

55:01

So basically you see an intrauterine pregnancy, and

55:04

then you also have findings suspicious for an ectopic-type

55:07

of pregnancy, so pregnancy outside of the uterus.

55:11

Um, and so that, that we touched on what

55:14

is the important, is there any importance

55:16

of the size of the yolk sac and outcome?

55:20

So we did touch on that as well.

55:21

So if the yolk sac is enlarged,

55:24

you know, that can be concerning.

55:25

Whoever you just follow that, that embryo or fetus.

55:28

Um, for other sort signs that the fetus may not be

55:33

doing well. Sometimes we see an enlarged yolk sac.

55:35

It doesn't mean anything.

55:36

In isolation, the pregnancy, um,

55:39

marches along just fine.

55:42

But it is concerning when you have other

55:43

ancillary findings that are suggestive of failure.

55:47

Um, how would you differentiate

55:50

an ectopic pregnancy from

55:54

other adnexal pathology, like an ovarian cyst?

55:59

So sometimes it can be hard. Your most,

56:02

um, things bouncing all over.

56:08

The most important thing is to try to do that.

56:11

Have the transvaginal probe pushed down on the patient's

56:14

belly, see if the ovary is separate from the structure.

56:18

Your clinicians are going to be

56:19

monitoring the beta hCG levels.

56:21

They're probably not rising appropriately.

56:25

You're not going to have a normal intrauterine pregnancy.

56:27

So all of those things go into these factors.

56:32

Um, when you're deciding whether or not

56:34

it's an ovarian cyst, an ectopic adnexal

56:36

pregnancy, there's lots of variables going on.

56:39

Um, for viability, when do you recommend a 10-day or

56:45

14-day, two-week follow-up? Does it matter?

56:50

So I recommend a 10- to 14-day follow-up if it's an

56:54

early IUP because I haven't been able to date, give

56:57

the clinician dating and viability, and I will recommend

57:01

a 10- to 14-day follow-up if I'm concerned for, uh,

57:04

failed ultrasound findings, suspicious for failed pregnancy.

57:08

Those are the two situations where

57:09

I commonly will recommend that, um,

57:15

if UPT is weakly positive and beta hCG level is slightly

57:19

high or corresponding to three to four weeks,

57:22

but ultrasound is normal, and I don't understand this

57:27

question, so whoever wrote it, maybe if you want to,

57:31

um, type it in again. Amniocentesis or chorionic villus

57:39

sampling, which test to be done and how to decide?

57:41

So in our practice, um, we allow that

57:44

decision to be made by our OB-GYNs usually.

57:48

Um.

57:50

What we end up doing is finding things that are

57:53

concerning, like that increased nuchal translucency,

57:56

and then we recommend the cell-free DNA.

57:58

And at that point, the cell-free DNA is abnormal,

58:02

concerning for chromosomal abnormalities.

58:04

And certainly the patient can go on to have, um,

58:07

amniocentesis and CVS sampling at that point.

58:12

Um, that's not really a thing, something

58:14

that the radiologist is deciding.

58:16

Um, somebody asked why not heterotopic pregnancy in the

58:21

previous case. I'm not sure what they were referring to.

58:24

Sorry.

58:24

Some of these are real-time comments.

58:28

Um,

58:32

A lot of questions on heterotopic pregnancy differentiate.

58:36

Ruptured corpus luteal cyst

58:38

and ruptured heterotopic pregnancy.

58:40

That is very difficult.

58:43

Um, can you elucidate on concordance.

58:46

Can you elucidate on concordance

58:49

of dates with LMP ultrasound?

58:51

So I'm not sure concordance of dates.

58:55

So what I do is, um, you want that dating.

59:01

So when I have a patient that I'm dating and I'm looking at

59:04

for dating and viability, it's usually less than 14 weeks.

59:08

My sonographer asks the patient, what was your LMP?

59:13

And then my sonographer gives me the

59:15

estimated due date by the patient's LMP.

59:17

And then she does the study and she does a crown-

59:20

rump length three times and takes an average, which

59:23

spits out, the machine spits out the EDD for me.

59:27

So then I take the ultrasound EDD and the

59:31

patient LMP EDD, and I compare the two.

59:34

If they're discordant, meaning five to seven days

59:37

plus or minus in one direction, I go with the

59:40

ultrasound dating, 'cause that's most accurate.

59:42

If they're concordant, meaning they're within five to

59:45

seven days of one another, I go with the patient's LMP.

59:49

So I hope that clarifies that.

59:52

So primarily that's measured three

59:53

times. You can compare the two dates and figure

59:56

out if they're discordant or concordant.

60:00

Can there be two ectopics in a tube?

60:06

Yes.

60:06

I've never seen it.

60:09

Depends on if there were two eggs and two sperm

60:11

fertilized that didn't make it into the uterus.

60:13

Right.

60:13

So that would be very unusual, um, for a

60:20

monoamniotic twin pregnancy.

60:25

Best way to tell mono- or dichorionic.

60:31

So that is describing

60:34

how many placentas there are.

60:36

So if you see one placenta, you don't,

60:39

there's nothing else to worry about there.

60:42

I'm not sure I understand the question.

60:44

Um,

60:48

'Cause you're not going to have a di-

60:49

chorionic and a monoamniotic pregnancy.

60:52

You would have a di-di.

60:55

Um, how to accurately measure

60:58

fetal heart rate during the scan?

60:59

So they're using the M-mode.

61:01

So the, the sonographer places, uh, hits something.

61:06

Um, the M-mode setting on the ultrasound, they get

61:09

over the fetal heart, and they measure that, um,

61:13

and that cycle, um, until they can get a regular

61:17

B tracing, and then they put their caliper on the

61:20

tracing, and that's the average fetal heart rate.

61:24

Um, so it's sort of something that

61:25

the machine spits out for us.

61:30

Using color Doppler in early pregnancy.

61:32

Not recommended.

61:33

Yep.

61:34

We talked about that.

61:36

What age?

61:37

Ossification of cranium is seen

61:39

around eight weeks’ gestation.

61:43

Um, may you please give another one

61:46

for second and third trimesters?

61:49

Sure.

61:50

Um, are failed pregnancy and

61:53

blighted ovum used interchangeably?

61:56

I don't use the term blighted ovum, so I would have to

61:59

get back to you on that one. Role of progesterone levels.

62:03

So, um, that's a good question.

62:05

Oftentimes our clinicians, our OB-GYNs,

62:08

will send a patient to us with concern for

62:12

either a failing pregnancy or an ectopic pregnancy.

62:15

Usually it's failing because it's

62:16

not progressing appropriately.

62:18

And they'll say progesterone

62:19

levels not rising appropriately.

62:21

So that's again another clinical, um,

62:24

indicator that the clinicians are looking at.

62:26

And then we get that information when we're doing either

62:29

their dating and viability or follow-up viability studies.

62:34

Um, can you please explain dating and

62:37

the rule of five and seven days again?

62:41

I think I did that.

62:43

Do you, does um, would you like me to

62:47

go back on my slides and describe that again?

62:49

Basically, it's just—

62:51

If the gestational age is just a

62:53

certain age, you go by five days.

62:55

If it's a, if it's greater than

62:56

that age, you go by seven days.

62:58

If you just think in your head five

62:59

to seven days, you can't go wrong.

63:01

So if you're discordant five to seven days, um, with the

63:05

LMP EDD and the sonographic EDD, you cannot go wrong.

63:09

So you don't have to finely parse that down.

63:11

That's just what we do because

63:13

we're an academic medical center.

63:15

Um, but I think that you really can't be faulted

63:18

if you say plus or minus five to seven days.

63:22

Could ovarian hyperstimulation exist?

63:26

Coexist with pregnancy?

63:27

Yes.

63:30

You know, a lot of times patients are being put on

63:32

medications for infertility that cause their, um, ovaries

63:36

to be hyperstimulated, and so then they happen to get

63:39

pregnant, and we will see very large, cystic replaced

63:45

ovaries with fluid in the pelvis and a pregnancy.

63:48

And you don't want to.

63:51

You don't want to say, oh, does this patient have

63:53

bilateral serous cystadenomas, for example?

63:57

Um, you want to have that history of, oh, the patient was

64:00

on Clomid before she got pregnant, to know, um, what that was.

64:05

And then, let's see, ultrasound shows no

64:10

intrauterine or extrauterine pregnancy, and the beta

64:12

hCG is slightly high. Then how to follow up?

64:15

So I think that you're asking, you have a pregnancy

64:19

of unknown location, but you have a positive beta hCG.

64:23

What should you do?

64:25

You're going to want to follow up that pregnancy

64:28

because you want to, you want to, if it's a normal pregnancy,

64:31

you're going to want to check it for dating and viability.

64:34

If it's an ectopic pregnancy, then the clinician is usually

64:38

tracking the beta hCG.

64:40

So trending the beta hCGs, and

64:43

if the patient is stable, they'll probably get a

64:46

follow-up to see, okay, can you now see an adnexal mass?

64:49

Is there anything that's coming into the uterus?

64:53

Um, and so it's kind of a mix.

64:55

You can recommend a follow-up, or you can

64:57

let it be up to the clinician.

65:00

So they're trending all of these labs in the

65:02

background, and we're reading the images for

65:04

them, and the whole story has to come together

65:06

in the setting of pregnancy of unknown location.

65:08

Typically, they get a repeat ultrasound because they're

65:10

going to need to, um, check the baby for dating and viability.

65:16

Diagnosing interstitial pregnancy.

65:17

I'm going to skip that because I could spend

65:20

a lot of time talking about interstitial,

65:22

heterotopic, and ectopic pregnancies.

65:25

Um, and for the sake of my time,

65:26

I have to get off this call soon.

65:28

So, so sorry.

65:29

Um, I can, um, perhaps if you put your, um, I don't

65:36

know, Ashley, if I wanted to send that person some more

65:39

reference articles on that topic to answer that question.

65:43

I don't know how to ask for that information.

65:48

We can have them send an email.

65:49

I'll send it in the chat.

65:50

They can send it to me, and I can forward it over to you.

65:53

Great.

65:53

That would be awesome.

65:55

Um, how to decide which invasive test

65:58

to do when soft markers are positive.

66:00

So that will be, um, pretty much determined by your, your

66:05

referring clinician, so that, that, that is a long discussion

66:10

with the patient, and it's patient comfort and, you know,

66:13

when to offer them an amnio or, um, an invasive test

66:17

versus doing just a blood draw, the cell-free DNA test.

66:21

So that is something that the clinicians

66:23

handle versus the radiologist in my practice.

66:27

Um, please give us one excellent fetal MRI.

66:29

Oh, you guys are so sweet.

66:31

Thank you very much.

66:32

And do you see a decidual cast?

66:35

I'm not familiar with that terminology.

66:38

Um, so I would have to look that

66:39

up and get back to you about that.

66:43

Um, what analysis do you like, FISH,

66:45

chromosome array, and how to decide?

66:47

Um, again, we use the cell-free DNA, which is a blood draw.

66:50

Um, I'm not, I, I don't, I'm not a proponent for

66:56

any particular, I don't have an opinion on whether

66:59

or not which one I like or which one is better.

67:02

I just know the one that we use, and it's

67:04

beyond my scope, really, as a radiologist.

67:09

IC bump?

67:10

That's a good question.

67:11

So I was going to include that in

67:12

my lecture, and I decided not to.

67:14

I mean, as you can see, I already went way over my time.

67:17

Um, IC bump, we can see that it's usually an

67:20

incidental finding, um, but you can describe it.

67:26

Uh, you can find it in early trimester,

67:28

and it can be described normally.

67:30

We see normal progression of pregnancy with the chorionic bump.

67:35

Perfect.

67:36

I appreciate you staying on a little longer.

67:37

I want to respect your time and let you get going.

67:40

Uh, so just as we bring this to a close, I want to thank you so

67:42

much today, Dr. Davis, for your time and your expertise, and

67:45

for all of you for participating in this noon conference.

67:47

A reminder that it will be made

67:48

available on demand at mrionline.com.

67:51

In addition to all previous noon conferences, this is made

67:53

available complimentary, and join us on Monday, Dr. Colleague

67:57

Gad will be with us on an imaging approach to jaw lesions.

68:00

Thank you so much, and have a wonderful day.

68:02

Thank you.