Pelvic Pain: Positive Pregnancy Test - HD

Introduction

I have no financial relationships to disclose.

Learning Objectives

Review features of ectopic pregnancy
and focus on some of the more uncommon types including cesarean scar
and interstitial ectopic pregnancy.

Discuss the physiologic changes
and common etiologies
for pelvic pain in the pregnant patient.

List our sonographic approach
for evaluating the pregnant patient who has pelvic pain.

Review of Ectopic Pregnancy

A brief review
of ectopic pregnancy.

This occurs when a blastocyst implants outside
the uterine cavity.

Most commonly the blastocyst will implant in different portions
of the fallopian tube as listed here, the ampullary
or isthmic part of the tube.

Much less common the blastocyst will implant in the
interstitial part of the tube at the cesarean scar
in the cervix, the ovary or the peritoneal cavity.

Classic Tubal Ectopic Pregnancy

This is a classic tubal ectopic pregnancy.
A radiologist will have no trouble making the diagnosis.

There's no IUP
and there's an adnexal mass containing a yolk sac
completely separate from the ovary.

Here's a cine clip
and if you follow the fallopian tube along,
you'll see the ectopic pregnancy
and that's in the ampullary
part of the fallopian tube.

Ectopic Pregnancy Facts

Ectopic pregnancy is not that common.
It is about 2% of all pregnancies,
but the true incidence is likely higher.

Most important to know is
that ectopic pregnancy is the leading cause
of death in the first trimester, up to nine
to 14% mortality from rupture of the pregnancy.

It is the onus of the radiologist
to make the diagnosis as 50%
of patients are asymptomatic
and up to 50% of patients will have no risk factors.

Risk factors for ectopic pregnancy include a prior
ectopic pregnancy, having a history of PID
or gynecologic surgery, in vitro fertilization, smoking,
congenital uterine anomalies and endometriosis.

Presentation Variations

The majority of ectopic pregnancy does not present as
that tubal ring as shown in that first image.

Rather, there have been studies that have shown this.
One retrospective study that is listed below showed that 54%
of ectopic pregnancy presented as a non-specific
adnexal mass separate from the ovary.

Role of Beta hCG

What about the role of beta hCG?

The most important thing for everyone to know is
that there is no lower level value cutoff that will exclude
ectopic pregnancy.

You can have a beta of 10
and still have a significant ruptured ectopic.

Echogenic Free Fluid

You get this case to read
and the technologist shows you there's no IUP in the uterus
and then you see this complex fluid in the pelvis.

What does that mean? The patient is pregnant.

The echogenic free fluid does suggest hemoperitoneum
associated with an ectopic pregnancy.

There were many reports in the literature stating a high
specificity for this finding.

But then there were subsequent studies that showed
that this echogenic free fluid is not specific
for hemoperitoneum from a ruptured or leaking ectopic.

This particular patient did have an ectopic pregnancy.

Case Examples

Show a case. This is a pregnant patient
who came in with acute onset of pelvic pain.

What do we do first?
We always start with the transabdominal survey.

We want to be able to get an overview
of what's going on in the pelvis.

Is there a hemoperitoneum? Are there masses in the pelvis?

If we see abnormalities,
we want to survey up higher in the abdomen.

These three images show very amorphous
and complex looking material within the pelvis that are kind
of outlining the bowel loops.

It's very difficult
to delineate any clear anatomy within the pelvis.

Here's a transverse image of the uterus.
There is no IUP visible and we look up in Morrison's pouch
and there's a large amount of fluid there.

We know that this patient has a lot of hemoperitoneum.

This patient went to the OR
and had a ruptured left tubal ectopic pregnancy.

She had a hemoglobin of eight.
She had three to four liters of blood within her pelvis.

Now contrast that patient with this one.
This woman was pregnant
and also had an acute onset of pelvic pain.

The arrows are showing some
hemoperitoneum within the pelvis.

There was a normal right ovary,
the left adnexa looked like this.

There was some blood clot
and amorphous material, an enlarged left ovary.

This patient went to the OR to have a second look.
She had a ruptured left corpus luteum
and the arrow there points to the blue arrow,
shows an early IUP with an intradecidual sign.

This patient, her report initially was read out
as ruptured left ectopic pregnancy.

The gynecologist who was taking care
of this patient called me
and said, I think that there might be a pregnancy here.
Do you agree an IUP? I said, absolutely.

This is a case that shows that
hemoperitoneum is not specific for ectopic pregnancy.

Do not give methotrexate in the setting of a potential IUP.
Patients who are unstable
or who have a lot of pain need to go to the OR
for further evaluation.

Differentiating Corpus Luteum from Tubal Ring

Take a moment to discuss how
to differentiate the corpus luteum from the tubal ring
of ectopic pregnancy.

Sometimes these two appearances can look similar
and it can be a diagnostic dilemma.

Some of the differentiating features are
that a tubal ring will appear more echogenic than
the ovarian parenchyma.

The tubal ring, which is composed of trophoblastic material,
can appear similar in echogenicity as the endometrium
and the corpus luteum is less echogenic than the ovary
and less echogenic than the endometrium.

What about the role of color Doppler?

This image, this set of images will show you.

This is a tubal ring of an ectopic.
The color Doppler shows a ring of flow.

This is a corpus luteum also showing ring of flow.

The color Doppler is not helpful.

Are there other things that we can do
to differentiate a tubal ring from a corpus luteum if
they're adjacent to one another?

In this case this is adjacent to the ovary,
but we can also use something called the sliding sign
and apply transducer pressure to show
that one moves separate from the other.

Heterotopic Pregnancy Case

Want everyone to take a look at this case
and tell me how they would read it out.

This is a pregnant patient who had pelvic pain.
She was G5 P3,
P3 meaning three pregnancies and had one
and one child.

If you look here, there is a sac like structure.
She had an IUP
and then in the pelvis she also had
another sac like structure.

This was read out as IUP next case.

What happened to the patient?
She came back four weeks later.

Now we have a hemorrhagic mass in the area of
this sac like structure and also hemoperitoneum.

This was read out as changes of spontaneous abortion
with a ruptured hemorrhagic cyst.

This patient went on to get a CT scan
and the person who read the CT scan said,
let me look back at the initial images
and saw that there was a tubal ring
of ectopic pregnancy on the first scan.

They finally made the diagnosis
of heterotopic pregnancy.

Do not let the presence of an IUP
prevent you from calling a concomitant ectopic pregnancy,
particularly in patients who are at increased risk, those
who have history of ectopic
who have had assisted reproduction.

If you also look here, this tubal ring is as echogenic
as the endometrium here and that's another clue.

There's a yolk sac within this gestational sac.

This is the only case of heterotopic pregnancy
that I have seen, but call it when it's there.

Uncommon Ectopic Pregnancies

Cesarean Scar Ectopic Pregnancy

Moving on to a different pregnant female
who had heavy bleeding and pelvic pain.

These are two transvaginal images of the uterus.
It's showing a sac
that looks low lying within the endometrial
endocervical canal.

If you look on the transabdominal image, you'll see
that the sac is actually located at the cesarean scar.

This white arrowhead points to that cesarean scar.

This case had initially been reported as
a spontaneous abortion in progress.

This is a different patient showing
how color Doppler can be useful in showing the
implantation site of a pregnancy.

The arrows are pointing towards trophoblastic flow
in this sac that is implanted in the
anterior lower uterine segment.

We also see that there's cardiac activity within the embryo.

Here's the corresponding MRI that had been performed,
showing clearly that this is a cesarean
scar ectopic pregnancy.

This is another patient who had a low lying sac,
low lying gestational sac, also interpreted
as spontaneous abortion in progress.

The M mode shows
that there's regular cardiac activity.

This is a cesarean scar ectopic pregnancy.

If we look back at the initial transabdominal
survey, the arrow is showing the exact location
of the gestational sac implantation.

This patient came back nine days later
and this is how I got to see the case.

I got to see the case when the sac had passed,
but there were retained products of conception manifested
by increased color Doppler flow with low resistive index.

The cesarean scar ectopic pregnancy is one that I see
commonly missed, commonly interpreted as
spontaneous abortion in progress.

It's crucial to elicit the history
of C-section from the patient
or see that divot in the anterior lower uterine segment.

When you're looking at the uterus, though it's reported
to be rare, I think that the incidence is likely higher
and it requires a very high index of suspicion for diagnosis
as most patients
or a high degree of patients are asymptomatic.

The imaging findings, the transabdominal scan,
I believe the large field
of view images are really key in telling where
that sac is located.

Also, you'll see this empty uterine cervical canal
and then the color Doppler flow can show
trophoblastic flow.

It's very important
to differentiate from a spontaneous abortion in progress.

If you're not sure, it does no harm
to recommend close interval follow-up, you just need
to suggest this in the diagnosis.

This is an example of the history
that our technologists take on our patients.

We get all kinds of information when their last menstrual
period was if they've had a C-section,
any myomectomy, anything else.

Cervical Ectopic Pregnancy

We even asked them what their favorite color is.
Just kidding. This is a different patient
who was pregnant with vaginal bleeding.

There is a low lying sac.
The sac is located in the endocervical canal.

It is below the level
of the internal os on this coronal 2D reformat.

There's a yolk sac within the sac.

The M mode shows cardiac activity.

This is a cervical ectopic pregnancy.

We know that if there's a heartbeat within the embryo
that it must have implanted at that site.

This is another one that is often confused
for spontaneous abortion in progress.

Recommend a follow-up study if you're not sure,
cause cervical ectopics will persist.

It's important to diagnose this entity early
because if a D&C is performed, that can lead
to significant hemorrhage
because there's no muscle within the endocervical wall
to stop the bleeding.

Interstitial Ectopic Pregnancy

Want each of you to take a moment
to take a look at these three different pregnant patients
who have pelvic pain.

One of these is an ectopic pregnancy.

Just in your mind,
think about which one you would call as ectopic
and then I'll go through all these cases.

These are all transverse images of the
uterus with the sac.

Let's look at the first two.

The first one on the left is an IUP
angular intrauterine pregnancy.

The IUP angular is when the gestational sac implants
in the upper lateral aspect of the endometrial canal
medial to the utero tubal junction.

There's a large broad-based connection
with the endometrium.

The interstitial ectopic pregnancy is when the pregnancy
implants in the intramural portion of the fallopian tube.

These blue arrows show
that there's a broad base connection of the sac
to the endometrium with the IUP angular pregnancy.

On this side, the arrows are showing
that there's a thin band of myometrium separating the sac
from the endometrial cavity.

It can be a difficult 2D diagnosis.

At my institution we do 3D ultrasound
and get the coronal view on all patients pregnant
or non-pregnant.

We have found
increased sensitivity in making this diagnosis
with the 3D view.

This is a coronal 2D view showing the location
of the interstitial part of the fallopian tube.

It's this little hypoechoic line.

This is a different patient showing an interstitial
ectopic pregnancy with the corresponding intraoperative
photo showing the bulging of the
gestational sac
and the increased vascularity in the arcuate vessels
that occur with the pregnancy.

This is a different patient
who had an interstitial ectopic pregnancy.

There's no IUP, there's a gestational sac kind
of bulging off the side of the uterine fundus.

You can see that there's an echogenic chorionic rim.
Trophoblastic tissue is very echogenic
and then there is an embryo with the yolk sac inside.

This was initially diagnosed
or interpreted as a right adnexal ectopic.

Technically that is partially correct,
it wasn't mentioned
that it was an interstitial ectopic.

It's important to differentiate between the two
because interstitial ectopic pregnancy is managed
differently from an adnexal ectopic in the different parts
of the fallopian tube.

Surgical management is usually used
to treat interstitial ectopic rather than methotrexate.

Here's a different patient
who had an interstitial ectopic pregnancy
and here's the cine loop showing
ectopic gestational sac in the
interstitial part of the tube.

Here, this is that thin band of myometrium
that separates the ectopic from the endometrium.

Also note how echogenic that this chorionic rim,
the trophoblastic tissue is
and how it's similar echogenicity to the endometrium.

Interstitial tubal ectopic is two to 4%
of all ectopic pregnancy.

The pregnancy results in a bulge in the uterine contour
lateral to the utero tubal junction.

It grows up to 12 weeks due to the surrounding myometrium,
but it leads to life-threatening hemorrhage if it is not
diagnosed before it ruptures.

There are many different signs
that have been reported in the literature
regarding interstitial tubal ectopic,
including an empty endometrial canal,
a myometrial mantle sign.
The interstitial line sign, the bulging sign.

I do think that the hypoechoic myometrium
that separates the inner border of the
echogenic ectopic sac from the endometrial cavity
and the coronal 3D showing the exact location
of the sac, I find those two to be the most helpful.

What about case number three? Where's this pregnancy?

I didn't discuss until now the presence of an IUP
or gestational sac in a uterus with the mullerian duct anomaly.

This patient had an IUP in the left uterine horn
of a sub septate uterus.

Look at how it looks like there's a bulging of the uterus
and how it can be confusing.

This is a case that one of my colleagues called me about
and said, can I get a second opinion?
I'm not sure where this pregnancy is located.

These are transverse and sagittal images of the uterus.

Would you call this an IUP
or would you call this an interstitial ectopic pregnancy?

How many of you have read these reports?
This appears to be a possible borderline indeterminate,
equivocal suspected possible probably
of questionable significance.
Clinical correlation needed,
maybe interstitial ectopic pregnancy cannot be excluded,
but it's probably an IUP.

How useful is that to our clinical colleagues?
It's not. This one on the coronal 3D, there's no question
that it is an intrauterine pregnancy.

How about this case?
It looks like there are two endometrial canals.
There is a rim of myometrium around this
gestational sac.

There's some bulging of the uterine contour.
This is pointing to two different cervical canals.

This was an IUP in the left uterine horn
of a complete septate uterus.

In which of these is an ectopic? It was number two.

Physiologic Changes in Pregnancy

Now change gears a little bit
to the pregnant woman.

What are some of the anatomic
and physiologic changes that occur during pregnancy?

The changes of pregnancy can mask
and delay appropriate diagnosis.

I know this because I have been pregnant two times.
My second pregnancy was with twins
and I had significant symptoms during that pregnancy.

I know the dilemmas
that clinicians can face when a pregnant
patient has pain.

What happens with the gravid uterus?

The gravid uterus will start compressing the IVC
after 20 weeks and it wreaks all kinds of havoc
because it displaces the appendix and the diaphragm upward.

It compresses the distal right ureter.

In addition, the maternal physiology of
hypercoagulability leukocytosis the increased blood volume
as well as all the hormones, the progesterone
and the prostaglandins result in decreased muscle tone
and then can result in physiologic collecting system
dilatation as well as lax ligaments.

The abdominal pain, nausea, vomiting,
which are very common symptoms in a normal pregnancy can
overlap with pathology and it really causes a diagnostic dilemma
and challenge to differentiate pathology from
underlying normal physiology.

Imaging Approach for Pelvic Pain in Pregnancy

What does the ACR say?

The ACR recommends ultrasound as the first line test
to perform in a pregnant patient
with acute pelvic pain when non gynecologic
etiology is suspected.

Ultrasound when gynecologic
etiology is suspected.

Go through a few cases.

Appendicitis Case

This is a case of a pregnant patient
with right lower quadrant pain
and we've had several wonderful lectures today
about appendicitis.

This is a patient who had acute appendicitis
and it's the same appearance as in a non-pregnant patient.

Here's a cine loop showing a thick appendix.
There's an increased echogenic submucosa,
increased echogenicity of the adjacent fat.
There's a little lymph node.

She had an acute appendicitis.

This was a different patient who had
a non-diagnostic ultrasound.

Perhaps if we had done some of the tips
that Dr. Jeffrey mentioned, we would've found her appendix.

Her appendix is fluid filled
with inflammation on this axial T2 weighted image
and sometimes MRI is performed in patients
who have difficulty finding the appendix on ultrasound.

I don't want to go into the technique too much except
to say that it is technically difficult in the third
trimester and LPO
or left lateral decubitus position should be attempted as well
as the transvaginal approach.

An MRI is used at my institution for problem solving.

Other facts about appendicitis,
the acute appendicitis is the most common cause
of an acute abdomen during pregnancy.

It's important to diagnose this early
because it can result in fetal loss up
to 20% if the appendix ruptures.

Adnexal Torsion Case

This is a different patient she was 10 weeks pregnant
with right lower quadrant pain.

We have images of a slightly enlarged ovary.
You can wonder if there's some increased echogenicity
of the ovarian stroma.

This was mentioned
but the patient was doing clinically better with medication,
but the next day she got much worse.

She was re imaged and now the ovary has markedly enlarged
and she has marked stromal edema
and she had a right adnexal torsion.

As mentioned in the previous lecture, there is a
slightly higher increased incidence of adnexal torsion
during pregnancy due to the lax ligaments.

It occurs earlier in the pregnancy, usually
between the sixth and 14th weeks of gestation.

Hydronephrosis Case

This is a different patient, 20-year-old female
with right flank pain, 33 weeks pregnant.

This is one of the most common things
that presents itself to my ER,
ultrasound technologists and staff.

We have a right kidney that has hydronephrosis
or is it physiologic dilatation due to pregnancy.

What can we do? We look carefully
to see if there's any perinephric fluid.

We look for any renal calculi.

We compare echogenicity right to left
and also within the kidney to see if there are any areas
that are more echogenic or more swollen than other areas.

We can compare the resistive indices of both kidneys.

There are studies that have shown that
an increased resistive index in the side that is dilated
can be due to obstruction rather than
physiologic dilatation.

We can also look at the urinary bladder for jets.

If you do not see a ureteral jet in the supine
position, what you should do is turn the patient left
lateral decubitus
and then you can often get a right ureteral jet.

That's because if you think about it,
the uterus is compressing that distal ureter
and you want to move that uterus off of the ureter in order
to enhance urine peristalsis down the ureter into the bladder.

This was a patient
who had physiologic dilatation of pregnancy.

Comprehensive Imaging Strategy

We have a pregnant patient
who had right lower quadrant pain.

We confirmed an IUP.

This cine loop shows that there was a normal appendix,
there was a little bit of gas within the lumen,
there was no surrounding inflammation.

What do you do next?
Do you just send the patient back up to the ER
and say normal appendix IUP?

The technologist in this case said,
I think that this patient had a lot more pain
than I would expect.

This leads me to how we do it.

This is our imaging strategy for pregnant patients
who present with abdominal or pelvic pain.

We make sure the patient has an IUP,
but if we find the appendix
or the right lower quadrant ultrasound is not
revealing, what do we do?

We survey over the area of pain
and we also take images of the gallbladder.

We look at the kidney for stones, pyelonephritis,
perinephric fluid, examine the ureter,
look at the urinary bladder for debris, look for jets.

Make sure that the appendix
and the adjacent bowel looks normal.

Look at the ovary.
Make sure that it also is normal size without signs
of hemorrhagic cyst or abnormal corpus luteum.

Also important to look for any fibroids
or masses within the pelvis.

We actually created a new exam code in our
system
where we have combined an ultrasound abdomen limited
with an ultrasound pelvis limited so
that we can scan both the abdomen and the pelvis
and survey these common areas that can be cause for pain.

We did this because we saw too many patients
with these negative appendix ultrasounds.

Then go on to get an MRI of the abdomen and pelvis
and they were found to have pyelonephritis
or acute cholecystitis or an obstructing calculus.

We thought why not do some additional survey images while
we have them on ultrasound and really add value
and make the diagnosis the first time around.

That patient that I showed you the normal appendix,
we surveyed the right kidney
and we saw some perinephric fluid.

We saw a dilated ureter.

We found a stone within the distal ureter
with color Doppler twinkling artifact.

She had an obstructing right
ureterovesical junction calculus.

Here's a different pregnant patient
who had right flank pain.

We see a normal ovary.

There's this little echogenic structure
within a thick wall tube.

If we look at that on the sagittal,
she had a distal UVJ calculus with urothelial thickening
that was causing her pain.

This is a different pregnant patient
who had right lower quadrant pain.

The appendix was not identified.

She had an IUP, her ovaries were normal, she was discharged.

She came back two weeks later,
but this time the technologist took an image
transabdominally and then we could see
that she had a degenerating fibroid
and that was the site of pain.

I put this in to make sure to remind everybody
that you need to start with your transabdominal images
to make sure you don't miss these exophytic fibroids
or other masses
or free fluid
that could be missed if you just use
the small field of view transvaginal images.

This is a different patient
who had a degenerating fibroid.

This is the IUP, there's a large heterogeneous fibroid.

This patient had pain over the fibroid
and then three years later you could see
how the fibroid shrinks
and it has that classic peripheral calcification
that occurs in degenerated fibroids.

Fibroids are prone
to degeneration in pregnant patients due to rapid growth
of the uterus and decreased blood supply to the fibroid
during pregnancy.

Endometrioma Case

I'm going to end now with two of my favorite cases.
These are cases that I think
were very important in my career.

If I look back, you have some,
you have these cases that really meant a lot
to you and taught you things.

These two cases were very important to me.

This is a pregnant woman who was in the second trimester
and she had an adnexal mass on the ultrasound.

This is in the cul-de-sac
and we see one structure on the right
and the other on the left we see echogenic nodules with
vascularity, particularly on the left side.

I want to show you cine loop
showing how there's all of these echogenic nodules
that are within these bilateral cystic structures.

We thought that these were ovaries containing
endometriomas and we thought that this was decidualized
endometriosis within the endometriomas.

You can catch a glimpse
of the fetal head right here.

She had an MRI
and it showed the classic appearance of endometriomas.

We have T1 fat suppressed images showing the T1
hyperintense hemorrhage.

She had bilateral increased
signal intensity in these nodules
that represented the decidualized endometriosis.

We followed her.

Every four weeks she came back for ultrasound.

This went to
this actually resorbed three months after delivery.

It was the longest six months of my life
that I held my breath until she came back.

I got to see that these went away
because what can happen is they can be mistaken
for malignancy as they mimic ovarian cancer.

The teaching point is that the T2 signal
of the mural nodule should be isointense to the
endometrium.

These should be monitored,
but know that this can occur in pregnancy.

Intussusception Case

The last case is this is a pregnant woman
who was 32 weeks pregnant and she had significant pain.

They ordered her right upper quadrant ultrasound
and the tech said,
I think she has acute
cholecystitis cause she has so much pain.

I saw that the gallbladder was moderately distended
with a little bit of sludge.

The wall was thickened, but it just didn't seem
acute cholecystitis, like it wasn't ballooned out.

I said, what about all these other structures?

We went back in and I took a look
and I asked the patient, did you ever have any surgery?
Because it looked like there was bowel within bowel
and an intussusception.

This was her cine loop that I took.

She had had a gastric bypass
three years earlier.

What happened was she had a
jejunojejunal intussusception with ischemic bowel.

The general surgeon took the patient to the OR
and found that it had been necrotic
and he actually did a resection and another anastomosis
and he was able to save the mother
as well as the pregnancy.

Those pregnant patients are at increased risk for
jejunojejunal intussusception.

Final Thoughts

Imaging the pregnant patient
with acute abdominal pelvic pain should
start with ultrasound.

Confirm an IUP and exclude ectopic pregnancy.

Have a high index of suspicion for cervical interstitial
and cesarean scar ectopic pregnancy. 3D ultrasound increases
sensitivity and also increases specificity
and gives you more confidence.

Remember to take the TA images first
and remember to use decubitus imaging for jets.

Consider transvaginal imaging for the appendix
and distal ureteral calculi image
where the patient has pain.

Be the Sherlock Holmes of that patient.
Broaden your search pattern, figure it out, add value
as a radiologist to your patients.

Thank you.