Acute Pelvic Pain in the Non-Pregnant Female - HD

Introduction

Hi, I'm Lori Stakowski.
I'm a clinical professor at University of California San Francisco,
and the chief of ultrasound at San Francisco General Hospital.
Today I'm gonna be talking to you about acute pelvic pain in the non-pregnant female
and the role of ultrasound.

Acute Pelvic Pain in the Non-Pregnant Female

Acute pelvic pain in the non-pregnant female.
As we know, this is a very common cause of both hospital
and outpatient visits every year for women in their twenties and forties.
There has known to be about a 30 to 40% surgical misdiagnosis rate,
which is why imaging has come to play a very important role.
And we all know occasionally the triage nurse in the emergency department is often
ordering the ultrasound before the patient has even seen a clinician looking at the impact of sonography.
There was this nice study out of Children's Hospital in Harvard, in 1999
that surveyed both senior surgical and ER staff,
looking at women and young adults, females who came in
with lower abdominal and pelvic pain.
And they found that after their ultrasound,
their most likely clinical diagnosis was revised from what they thought before the ultrasound about 52% of the time.
And also their initial treatment plans changed about 50% of the time.
So again, ultrasound is extremely important in this clinical setting.

ACR Appropriateness Criteria

Now, when we look to the ACR appropriateness criteria for the best imaging modality of choice, we found that,
for acute pelvic pain and the non-pregnant female of reproductive age,
and again, this is non-pregnant because there's gonna be different criteria if the beta is positive,
but when a gynecologic etiology is suspected,
ultrasound received a rating of nine,
which would be the most appropriate tests with MR being six and CT four.
If a non gynecologic etiology is suspected,
then CT would be the most appropriate test with a rating of nine, ultrasound received a rating of seven RI six,
unless of course they thought that the leading diagnosis was either appendicitis or of the urinary tract pathology,
then ultrasound may be more appropriate to minimize radiation exposure to these young women.

Etiologies

Now our etiologies can pretty much be separated into two major categories, those that are of gynecologic etiology or non gynecologic.
Pretty much we think of it this way to know who the patient should next be referred to for further evaluation.
We're first gonna address our gynecologic etiologies with the top three being ovarian cysts, pelvic inflammatory disease, and torsion.

Pre-Imaging Checklist

Now our pre imaging checklist, before you even start interpreting your exam,
I always like to make sure we've reviewed the labs, make sure she is indeed not pregnant.
Check your urinalysis blood cell count,
if they had some blood drawn review, your clinical history.
Most importantly, I wanna know when their last menstrual period was, if they've had any prior surgical,
or gynecologic history.
And then reviewing any prior imaging studies can also be very helpful.

Ultrasound Technique

The technique we always start transabdominal.
You're gonna need a full urinary bladder,
use about a two and a half to eight megahertz curvy linear or sector probe.
We always image in Morrison's pouch looking for free fluid between the liver and kidney there.
We do take a quick shot of the kidneys,
and the urinary bladder, particularly in the regions of the utero vesicular junction,
and then the uterus and adnexa.
And then I always remember to ask the patient at the end for the point of maximal tenderness or pain to make sure
that I've included that within the field of view.

Now for endovaginal, now you're gonna have to empty their bladder, elevate their pelvis,
because often they're anteverted, anteflex, and you really have to get that probe down.
And sometimes the table will be in the way if you don't elevate their pelvis enough.
Typically today we're using five to eight megahertz probes for endovaginal.
You wanna get longitudinal and transverse images as well as color doppler as needed,
imaging the uterus, endometrium, and then in our the fallopian tubes and the ovaries.

Ovarian Landmarks

So it's important to remember our ovarian landmarks to know where to find the ovaries.
If this is the ovary right here, sitting medial to our iliac vessels, we have the ovarian ligament that's holding it in place.
And we know that we're gonna get a dual blood supply from the ovarian artery right off of the aorta as well
as branches from the uterine artery.
So again, the ovary can't be too far away from this from these structures.
And so if you image in the transverse plane, very importantly, go up towards the cornual portion of the uterus, aim a little bit towards that ovary,
and you will almost always find the ovary right there sitting just medial to those vessels.
Putting on color doppler sometimes just helps me identify the vessels and also helps me identify what isn't filling in the follicles of the ovaries.
So that can be helpful. Another important thing, because often bowel is in the way obscuring our ovary,
is you can do what's called the endovaginal ultrasound assisted pelvic exam.
Basically, let's say there's a piece of bowel here, obscuring our ovary.
We put in the endovaginal probe.
You use your other hand that's not scanning.
So let's say your left hand, put it on their right hemi pelvis, aim your probe towards your hand, and then bring the hand and the probe together
and the bowel will move out of the way.
And it's amazing. You will find the ovary just kind of pops in the field of view.
So here we are on the left side, again, you bring your hand over the other side to their left hemi pelvis angle, that probe,
bring your hand in the probe together.
And most of the time, the ovary will pop into the field of view.
Sometimes the only problem is you don't have the other hand now to save the image,
but you can always quickly go back and send back to the images you need or ask for someone to help you during that.

Ovarian Cysts

Now, the most common cause of pain is ovarian cysts.
With physiologic cysts being the most common, we often have these large graafian follicles right around mid cycle.
And when they have pain at this time, this is what we call mittelschmerz.
This is an early corpus luteum.
Here we've got a nice hypoechoic rim around this nice cyst.
If you put on your color, you will often see that ring of fire.
And sometimes they're clear, but other times they'll have a little bit of hemorrhage within them.
They're very friable, and that's okay, that's a normal corpus luteum.
But the pain is usually a mild to moderate and self-limited.

Now, what causes severe pain is when what we have to realize is the ovary has these proprio receptors.
So they're sensing distension just like bowel.
When you get gas pain, when your bowels with gas, the ovaries are gonna hurt when they distend rapidly, either because of a lot of fluid.
So that could be a clear cyst or because of hemorrhage.
So here I'm showing you, we have kind of a classic hemorrhagic cyst.
We have this fishnet appearance or fibrin strands.
We have the concave margins.
We make sure there's no flow with color doppler imaging.
And sometimes you can even jiggle the probe a little bit, and you'll find that the blood clot tends to jiggle a little bit.
So that can alone be causing the pain or it can leak, or it can even rupture, can be the cause of the severe pain.

So here I'm showing you an example of a 23-year-old severe right lower quadrant pain.
She had a negative pregnancy test.
We're seeing a classic hemorrhagic cyst, again with our fibrin strands, a concave margin.
And in her cul-de-sac over here, we're seeing that free fluid with the echoes, that is blood hemoperitoneum.
So that was the cause of her acute pain.
Now the pain usually will typically resolve and the process will typically resolve.
However, occasionally, this can actually be life threatening here.
His example up in Morrison's pouch between the liver and the kidney, we've got free fluid, but it has those echoes.
That is blood hemoperitoneum, lots of hemoperitoneum down in this right lower quadrant.
And the culprit of this is this little hemorrhagic corpus luteum.
And this patient actually ended up going to the OR and requiring a couple units of transfusion.

Here's another case, transabdominal image.
We're seeing a lot of free fluid again, with those echoes.
Here's our uterus.
On endovaginal, we're seeing that free fluid, and again, it was just a little hemorrhagic corpus luteal cyst.
So we never know which one of these are gonna be very serious.
And it's important to just take a look.

Pelvic Inflammatory Disease

So now let's move on to pelvic inflammatory disease.
As we know, this is defined as an infection of the upper female internal reproductive system.
Incidence, at least in the US, is about a million cases a year.
Though they say about two thirds may go unrecognized, particularly from chlamydia, unlikely to cause death, only about 150 deaths per year.
But considered quite serious, obviously, since most of these women are under the age of 25,
probably more hearing are the statistics that it's costing us, at least in the US about $7 billion a year,
to treat both the infection, but also in the lost wages and the sequela of this disease,
which they say about 20% of patients after having PID will end up either with an ectopic pregnancy
because of the scarring chronic pelvic pain or infertility.

Now, the etiology of PID 90 to 95% of the time it's a sexually transmitted disease.
Again, either chlamydia or gonorrhea.
That's directly related to the number of sexual partners.
But occasionally this is a post-procedural event about five to 10% of the time.
So it's gonna be different organisms, staphylococcus, streptococcus mycoplasma, which can occur
after a normal childbirth or an abortion endometrial biopsy, or our imaging procedures
that we may perform if we're not careful using a good clean technique.
Hysterosalpingograms and sonohysterography.

The CDC, the Centers for Disease Control, said that PID in 2002, they confirmed that this is indeed a clinical diagnosis.
So on physical exam, the clinician needs cervical motion tenderness, uterine or adnexal tenderness and abnormal cervical discharge.
And one of the following tests to be positive, either a fever, an elevated white blood cell count, SED rate,
C-reactive protein, either a positive wet prep or mount or endocervical culture.
But findings on pelvic ultrasound or laparoscopy would also be considered a positive test.
And these are with increasing specificity.

Now, who needs imaging?
Those that have clinically suspected PID and a palpable mass severe illness or no response to oral antibiotics
after about 48 72 hours of being treated?
What when what's important to know is that PID typically occurs in the immediately post menses phase.
And that's because this little mucus plug that sits here will fall out with menstruation
and that bacteria that's in the vagina will climb up into endometrial cavity through the fallopian tubes.
And though it should be bilateral for some reason, it tends to be more often asymmetrically more on one side will get
some exudative pus that again, tends to occur for some reason, more on one side than the other,
but can definitely be a bilateral process.

Now at our institution, our ob-gyn colleagues liked for us to divide this PID into four phases, which help guide with treatment and management.
The first is an endometritis, myometritis second, it's gonna involve the tubes.
So a salpingitis or a pyosalpinx.
Next, a tubo ovarian complex.
And finally, a tubo ovarian abscess with endometritis myometritis on ultrasound,
the most common thing you will see is nothing.
It will look like a normal exam.
The sensitivity for ultrasound in making this diagnosis is only about 25%.
When we see findings, it will typically be endometrial thickening.
So again, they should be in the immediate post menses phase when the endometrium is very thin.
So if you see a thickened endometrium, if there's increased vascularity on your color doppler imaging, if you have intracavitary fluid, particularly
with echoes, that can be pus or seeing any sort of gas.
So echogenic dirty foci with dirty shadowing may be some gas forming organisms that is causing the infection.
In fact, in your immunocompromised patients, your diabetic patients,
you can get an emphysematous endometritis just like you get an emphysematous cholecystitis with marked thickening
of the endometrium and all of this gas that you see shadowing over here.
So just something to keep in mind.

Here is an example of a 35-year-old woman with pelvic pain, fever, foul smelling discharge,
and she did have cervical motion tenderness.
She has a retroflexed uterus.
So you see her fundus is over here on this longitudinal sweep.
And I'm showing you the cavity is distended with fluid, the endometrium is irregular.
There's all of these echoes within the endometrial cavity.
And this is what we would call, there's increased vascularity in the muscle as well.
I would consider this an endometritis. And myometritis.

The next phase is gonna be a salpingitis, and then a pyosalpinx.
So a tube filled with pus and the appearance on ultrasound may range from just seeing a thickened tube.
I'm showing you two cine clips here and the longitudinal and transverse.
And up here on the top, you can see again, we're near that cornual portion of the uterus.
Here's our ovary and capping that ovary around the top, we see this thickened tube, which is unusual
because we usually don't see normal tubes.
And so they can be thickened, they can be increased in vascularity as I'm outlining right here,
and showing you with color doppler imaging.
It may look when once it's filled with fluid, just like a tubular or a elongated cystic mass,
often it looks multiloculated and you might think it's an ovarian mass.
But as you turn on it, you realize that those aren't septa, they are indeed folds,
and these cystic areas are contiguous.
And this can mimic a hydrosalpinx.
However, what we have to remember that in then the clinical setting of clinically suspected PID,
this can indeed be an infected tube.

Now, and here I'm showing you an example as again, cine clips are just so helpful in this setting
because we're really appreciating the contiguous nature of the cystic component.
That again, I'm showing you on this static clip.

Now, as the process gets a little bit more advanced, you can see a very complex tubal process
with thickened echogenic walls.
Some people use five millimeters as the thickness to suggest that it's an acute process,
I usually am not really gonna measure it.
I'm just gonna eyeball it that the walls look a little thick.
But you're often gonna have these internal echoes.
You may see fluid debris levels.
Now, if you image, if you turn orthogonal on this elongated process like this, you'll often see what's called the beaded or cogwheel appearance.
What you're seeing are those thickened endosalpingeal folds of the tube that are gonna be equidistantly spaced around that tube.
And with color doppler imaging there, it's not uncommon to see peripheral vascularity.

So here's an example of a 19-year-old woman with pain fever, chills.
She also had a discharge. This is a cine clip.
Looking through this, again, it's a cystic mass, but you'll appreciate as we go through there, these little peripheral nodules, if you will,
but they're equidistantly spaced.
It's medial to the ovary, which is sitting right over here.
So I'm gonna show you the ovary is separate.
So we know this isn't an ovarian process.
Her ovary is still well preserved, but this is the tubal process.
And if I show it to you a little bit more res up here, that's kind of the beaded cogwheel appearance.
Those are those thickened endosalpingeal folds that help lead you to the correct diagnosis.
And they can be pretty ugly looking.
And if you didn't know that this happened to be a 17-year-old who was sexually active, had fever
and elevated white blood cell count and pain, you might think this is a neoplastic process.
But these tubes, again, the folds can get very thickened.
There's the ovary right there that's separate.
And this was a pretty advanced pyosalpinx.

Here's a 21-year-old woman pain fever discharge, palpable left adnexal mass.
She refused endovaginal imaging, which is not uncommon because they will have such extreme pain.
But you can make this diagnosis transabdominally as well, where appreciating kind of, again,
that elongated the contiguous folds of the dilated tube.
And right here on the right hand center, we have a fluid debris level.
So you can make the diagnosis of pyosalpinx, even transabdominally.

Now, once the process gets a little bit further, this pus is pouring out the end of the tube, the ovary,
it's starting to be affixed to the ovary.
The ovary is getting inflamed.
This is when we call it a tubo ovarian complex.
So you'll see some ovarian edema and indistinctness, maybe a little bit of hyperemia.
So I'm showing you in this case, again, that undulating appearance of the thickened tube.
Not a whole lot of fluid in there.
The most predominant finding is the thickness.
But over here I'm showing you there's a little bit of ovary with those follicles.
And that's what's telling me that's the ovary are those little follicles.
So there is some preserved ovarian parenchyma, but it's inseparable from this tubal process.
So that's why I'm calling it a tubo ovarian complex.

Here's another example. 34-year-old woman, right lower quadrant pain, fever, chills, discharge.
Now what you have to preach when we talk about fluid debris levels, you might say, well, that's not dependent echoes,
but remember, the endovaginal probe is coming in this way.
We are essentially rotating the image.
There's her belly, that's her buttock.
So really this is how we have the patient positioned on the table.
So those are indeed layering echoes.
That is the dependent portion, but this is how we tend to image it.
And I think you probably all know that.
But here we've got our peripheral vascularity and we look around and there are the follicles.
There are some preserved ovarian tissue.
So this would be a tubo ovarian complex.

Here's another example, A woman with a IUD in place.
And as we look in the transverse plane, we're seeing some big bilateral adnexal masses, kind of going this way as I show you a cine clip
through the left side.
Again, a very complex heterogeneous mass, but if I freeze right here,
you'll appreciate there are some preserved ovarian parenchyma.
Even this one happened to be bilateral.
A little bit more generous on that left side.
But even on the right side, we're seeing kind of a thickened tube,
and right there, there is a little bit of ovarian parenchyma.
So these were bilateral tubo ovarian complexes.

Now, once you have breakdown, you have destruction of the ovarian architecture from the infectious process
that is when we call it a tubo ovarian abscess.
And only about seven to 16% of cases of pelvic inflammatory disease ever progressed to this level.
On ultrasound, you'll see a very non-specific heterogeneous complex mass.
You may see some fluid levels or gas, but really these are just gonna be very ugly masses in the appropriate clinical setting.
So up here near the cornua, again, we're seeing that tube that's distended with this echogenic debris.
As we come over here, we're seeing a complex mass in the adnexa, and I'm seeing this free fluid with all of these echoes.
This isn't blood this time, this happens to be pus.
So this is peritoneum in the setting of a tubal ovarian complex.
I'm sorry, abscess. I'm gonna call it that because I don't see any normal ovarian parenchyma here.

Here's another example. Again, a transverse image.
There we have our little uterus in the transverse plane, a big adnexal mass over to the left hand side.
So I'm gonna show you longitudinal and transverse clips through that left side.
Let's freeze right here.
We've got big ugly complex heterogeneous mass.
Could not find a normal ovary again, in the appropriate clinical setting.
This is a tubo ovarian abscess.

Now, why is it important to differentiate these different phases?
Again, has to do with treatment.
So in the setting of an endometritis or salpingitis, they will typically treat with oral antibiotics
and only if there's no improvement in 48 to 72 hours would they require,
and again, if it was clinically suspected, once we make the diagnosis with ultrasound,
they may re-image if there's no improvement after that time with a tubo ovarian complex or abscess.
Often these women require hospitalization and IV antibiotics after they've shown demonstrated improvement.
After 24 hours, they may be converted to PO.
If there's no improvement, again in two to three days or any worsening symptoms, they may go on
to require some sort of drainage procedure or intervention.
But that only occurs about 15% of the time.

So here's a woman who had both a CT and an ultrasound.
We see kind of a tubular enhancing mass.
We see the walls enhancing on the CT.
On ultrasound, again, was just a very complex heterogeneous cystic mass.
She was on IV antibiotics.
Five days later, it's even getting worse.
It's getting a lot bigger.
So she went on to interventional drainage through a transvaginal approach,
which is much better tolerated for the patient than a trans gluteal approach.
And she did fine.

Now, what I want to show here is how important it is to always remember that this is a clinical diagnosis.
So the clinical setting has to fit.
This was a 13-year-old girl with a acute pelvic pain, fever, chills, white count.
She adamantly denied sexual activity.
She was sent for an ultrasound, on ultrasound.
We see that she's got a little uterus right here.
There's a fluid debris level, on her CT.
Oh, I'm sorry, we said that this was consistent with pelvic inflammatory disease.
So on CT here, we have kind of enhancing peritoneum,
but we look in the right lower quadrant and there is a kind of a fluid debris level right where her appendix should live.
And indeed this was a ruptured appendicitis.
And then we actually felt bad.
We should not have said that this was consistent with PID when she really did not have that sexual history or any sort of intervention.

Here was a 42-year-old married woman, monogamous.
As far as she knew her husband was monogamous, but she had pain, right adnexal tenderness,
mass fever even had an elevated white blood cell count and elevated SED rate.
And again, we're seeing on ultrasound transabdominally here is her uterus.
Over here pushed anteriorly from this very large tubular looking mass that's filled with all of this debris.
It looks like it has thickened walls here.
And she was actually treated for PID, never resolved, went to the OR, and this was endometriosis.
So the point I wanna make is that even with acute hemorrhage and the setting of endometriosis,
you can get an elevated white blood cell count, you can get a fever.
And but it the clinical history didn't fit.
There was no reason for her to have PID.
So we need to keep that in mind.

So my take home messages for PID is always correlate clinically.
Metritis may look normal on ultrasound.
You need to always make sure that you're providing the clinicians understand that a normal ultrasound does not exclude endometritis
in the appropriate clinical setting, a pyosalpinx can range from an anechoic tube.
So if I'm seeing what I think is just a hydrosalpinx, but they're clinically suspecting PID,
this can be actually a pus filled tube.
Most of these cases are sexually transmitted or again, iatrogenic something that we did some sort of intervention.
So you gotta make sure the clinical history fits.

Ovarian Torsion

Now moving on to torsion, pretty much anything in the pelvis can twist.
In fact, there was a recent article demonstrating that they had a gravid uterus completely twist upon itself,
which is very unusual and rare.
And for the most part, when we talk about torsion, we are talking about just the ovary with a little portion of that tube as well.

Now, no torsion is a noun.
If you actually look up in Webster's, there's no such thing as tors or tors that it's twist or twisted.
So you just need to keep that in mind.

Our risk factors for ovarian torsion, most of the time these are premenopausal women.
Average age is about 32 years old.
Many of them will have a history of prior pelvic surgery, about 40, 47%.
And many believe that's because we're loosening up those supporting structures in the adnexa.
Many will have a history of prior ovarian cysts.
They may be pregnant or on ovulation induction because they can get these big ovaries with these,
this was actually a ovarian hyperstimulation syndrome, but about half of them will have no risk factors at all.

Now, when we look at the presentation of ovarian torsion, I think it's suffice to say that it's quite variable.
Yes, most of the women will have report sharp or stabbing pain, but only about 60% will say that it was a sudden onset.
And about 50% of the women will complain of a similar episode within the preceding month.
The next most common finding is gonna be nausea or vomiting.
Whenever the woman says, oh my gosh, the pain was so bad, I actually threw up.
I'm really concerned about torsion leukocytosis.
56% not expected, right?
One may be thinking more along the lines of infection, pain radiating to the flank or back,
or groin, making you think maybe of a ureteral stone, fever, 18%, which is also somewhat unusual,
though peritoneal signs are uncommon.
But looking at this presentation, I think it's pretty easy to understand why.

When we look at the outcomes of ovarian torsion, the diagnosis is often missed.
It's really clinically not high up there on the differential often.
And the salvage rate has only been reported to be about nine to 19%.
So I think we can do better, both by our clinicians having a higher level of suspicion,
and us doing better with our ultrasound diagnosis.

So the most common finding that we will see is actually on gray scale ultrasound in seeing asymmetric ovarian enlargement.
We know that a normal ovary will typically measure about two by three by four centimeters.
Most, the vast majority of twisted ovaries will be greater than five centimeters.
In fact, sometimes in the setting of intermittent torsion, you can end up with a condition called massive ovarian edema,
where you can get up to 28 times normal volume of the ovary.
Surrounding free fluid around that ovary is the next most common finding.
About 87%, that I'm showing you right here, peripheral follicles that pearls on a string appearance about 74%.
This is transudation of fluid into those support follicles around the periphery of the ovary.

Here's an example of a 3-year-old woman with right lower quadrant pain for three days.
Their leading clinical diagnosis was actually appendicitis.
So they ordered the CT first, and our astute resident who was on call that night noticed that there's the uterus
and there's these two masses in the adnexa.
But this one over on the left, on this image probably shown better, we're seeing peripheral follicles.
So this is indeed a very enlarged ovary, recommended the ultrasound.
And I think on ultrasound, again, we're seeing those two masses.
Those are our peripheral follicles.
There it is on endovaginal imaging.
So very important findings with torsion.

This was a two day old female infant who had a palpable abdominal mass just below the xiphoid process.
And when we put the probe down over there, what are we seeing this complex mass.
But look over here, we've got peripheral follicles.
This is telling us that this is a big ovary.
There's hemorrhage. We see a level here.
This was a twisted necrotic ovary and a two day old female infant from torsion, again, due to,
she probably had a cyst or something from hyperstimulation, from those circulating maternal hormones
that were still in her system.
So that is what is important to know, is that in neonates you can have torsion of a normal ovary due
to those again, circulating hormones.
But even in children and teens, you don't have to have the mass.
They have very mobile mesosalpinx.
And often it is right around the onset of menarche with those first corpus lutei and graafian follicles that act as the point of twisting.
In adults, it is much more common to have torsion in the setting of a mass.
When the mass is there, it's much more likely 13 times more likely to be benign than malignant.
'cause we think that those malignant masses will adhere to the surrounding structures.
And the most common neoplasm to twist is the cystic teratoma with some classic features here
of the shadowing echogenic focus and the dot dash appearance.
And I want you to note that while we say, oh, it's really only four centimeters that it can twist,
or maybe this thing is too big to twist, really a mass of any size can twist.
I've seen little one centimeter masses twist.
I've seen 30 centimeter masses twist as well.

Here is transabdominal imaging.
Again, she was 13 years old, she was a virgin, so we could not perform endovaginal.
She had acute left lower quadrant pain and anorexia.
We're seeing a normal right ovary right here by the calipers.
Here is her uterus.
And there was this big mass centrally that we're seeing that shadowing echogenic focus.
Some do dash appearance. She had a dermoid.
If I've got a dermoid, I'm seeing a cystic teratoma in the setting of acute pain.
This is torsion until proven otherwise.
There's our dot dash, the focus, the shadowing.
And this indeed was proven torsion in the operating room.

This was a 51-year-old woman with increasing abdominal girth.
She had her ultrasound first.
We saw this approximately 17 centimeter mass that was very complex.
It was actually up almost up to 19 centimeters.
And we said this is consistent with ovarian neoplasm, low malignant potential, potentially malignant.
And later she was admitted.
About two days later, she had acute pain.
So she, we looked at this, she had this admission CT and I just wanna show you what this mass looks like.
And two days later it looked like this.
So there is her little uterus.
And what's interesting and what you can appreciate is her uterus is all the now all of a sudden, on the other side of her pelvis,
it moved from being primarily in the right side of her hemipelvis to the left side of hemipelvis,
as is this large mass.
These are again, the more complex features of the mass that are more on the left side.
Now on the right side, and this is torsion that was diagnosed on CT because it's almost like a mirror image
from her admission CT right there and there.
This turned out to be a low malignant potential mucinous tumor that had 450 degrees of torsion in the operating room,
but even small little masses can twist.

Here was a 34-year-old woman, acute left lower quadrant pain, nausea, and vomiting.
Again, I take that really seriously.
We're measuring her ovary here.
And on our sweeps, you're appreciating these little spherules and almost this ring down appearance.
This these are little cystic teratomas again, within this ovary that they really weren't able to see
because they're all intra ovarian.
But on color doppler imaging, I'm demonstrating both venous and arterial flow.
And yet because she had pain, we sent her to the OR 360 degrees of torsion.
And you might be wondering, huh, well that's unusual.
Why does she have flow if this is a twisted ovary?

So let's review our findings on color doppler in the setting of ovarian torsion.
Here's our schematic diagram again, at the ovary with the dual arterial supply.
We'll drop our cursor.
And typically we see a fairly average resistance, low resistance waveform in the arterial blood flow and our venous waveform.
With initial torsion, you will see a higher resistance waveform in the arterial pattern.
With the venous waveform still being present as it ensues, edema ensues.
Again, you still may have high arterial waveforms, but our venous waveform may go away.
We believe theoretically that these veins are more compressible.
And then eventually you will end up with a necrotic ovary and not be able to find either arterial or venous flow.

So let's look at this study.
It was a small case series of owing about 15 cases.
But they showed that there was neither arterial or venous flow and only about 40% of the cases no venous
with decreased arterial flow, which we think is the next most, the most common finding we're supposed to see was only 7% of the time.
Look at this, no arterial with decreased venous.
Now that doesn't make sense by what we think should happen at all.
And yet that was 33% of the time, decreased both 13% and normal flow 7% of the time.
So with the important take home message here is that torsion is not synonymous with the absence of flow.
You can still have flow and have a twisted ovary.

Here is a slightly larger case series.
It was about 33 cases they just looked at.
They didn't look at them combined, but just was venous flow absent or present was arterial flow absent or present.
And again, in a lot of these cases, about a third of the time, venous flow was present.
And this is going along more the lines of thinking again, that venous flow will be absent first,
but it's still 33% of the time you're gonna see that venous flow and about 50% of the time you're gonna see the arterial flow.
So torsion is not synonymous with the absence of flow.

Here's another example.
32 years old, intermittent right lower quadrant pain for several weeks.
I'm showing you some cine clips here through the right ovary and the left ovary.
You'll see on the right side there is a big mass.
It looks edematous.
Here it is our normal ovary on the left side, we've got a big ovary over here.
We're still seeing flow.
I'm demonstrating both arterial and venous flow.
And yet this was twisted four times when she was taken to the operating room.

I think what's more helpful is looking at this study from Art Fleischer, and it's an older study,
but it really to me takes home makes the most important point about the use of color Doppler in this setting is
that we should be looking at whether or not flow is present to determine whether or not that ovary is still viable,
not whether or not torsion exists.
So again, small series 13 cases that every time they found a little bit of flow,
the ovary was still viable when they took him to the OR whereas when they couldn't find anything, those were dead.
Those are the, if you're gonna wait for all the flow to go away, we're not gonna have a clinical impact
because we wanna find those that still have that flow present.
So again, you're gonna have to look at those other features on gray scale and the clinical setting to help make this a diagnosis.

Here's another example.
14 years old, intermittent, right lower quadrant pain going on for a week.
She's got a very edematous ovary.
We're seeing some peripheral follicles, arterial and venous flow, 720 degrees of ovarian torsion, but it was viable.
We were able to save this ovary.

Another case, 42 years old, acute, right lower quadrant pain.
She had a large palpable mass. They suspected a GI process.
So they got the CT first in her right adnexa, actually, this is almost in the lower abdomen
because again, it was coming out of the pelvis.
We're seeing this complex mass, but we have fat and calcification, so we know at least a portion of this is a cystic teratoma.
The degree of complexity was a little bit more than we would see with a teratoma.
These are her corresponding ultrasound images where again, we're seeing that shadowing echogenic focus.
But all of these complex septations, she had acute pain.
A portion of this is a dermoid seeing arterial and venous flow.
And again, this was torsion of a mucin cystadenoma containing a small dermoid.
So flow was still present.
And I'm telling you, these are all cases of proven torsion that we were able to salvage.

Now this was a recent case, a 22-year-old pregnant woman, the first trimester, right lower quadrant pain.
So she sent her to us really to look for appendicitis.
It was a rule out appendicitis. We did not see the appendix.
We're seeing her gravid uterus over here with the early pregnancy,
but there's a big mass over here in the right adnexa, we have a normal ovary on the left side,
we're seeing a big ovary on the right side.
And you say, well, yeah, that can just be her corpus luteum of pregnancy.
We're demonstrating arterial and some venous flow.
But it's a very edematous ovary.
The parenchyma is very edematous the impression said, consistent with prior torsion or detorsion,
because the radiologist who was in Germany said, well, there's flow, so there can't be torsion.
Maybe she had detorsion or now there's detorsion.
So they sent the patient home.
And my point is, while there's no doubt that this whole torsion detorsion phenomenon exists, right?
That's why these women have similar episodes within the preceding month.
It's often twisting untwisting, twisting untwisting, and then they eventually come for attention in the setting of acute pain.
It's really a disservice to the patient to suggest that the presence of flow means that there is detorsion
or not active torsion.
Again, think about it simply, if there's no flow, it's probably already dead.
And if you're seeing flow, it's viable.
And that is when we want to intervene here, she returned the next day.
Still in excruciating pain, we're seeing that hemorrhagic corpus luteum.
But look at the ovarian parenchyma around there, and I'm gonna freeze it here.
That is really, really thick and we're still showing a little bit of flow by the time they took her to the OR this now was a necrotic twisted ovary,
and she ended up losing her ovary, which I felt really, really bad about.
But look at how thick that surrounding ovarian parenchyma is now.

So I wanna show this point. I mean, we always see big masses in the ovary, right?
And usually when they get big, you know, you have to struggle to find that surrounding ovarian parenchyma, right?
It's really, really thin.
You're seeing the little peripheral follicle look at how thick that surrounding ovarian parenchyma is with a cyst of equivalent size, right?
So that should have been our clue to the diagnosis and hopefully would've prevented her losing her ovary,
not whether or not flow was present.

Now, another finding that's been described in the literature is something called the twisted pedicle sign or the target sign.
This is when you see a mass adjacent to the ovary with these concentric rings.
So there is the ovary, there's the twisted pedicle, that's basically your fallopian tube and the broad ligament
and the vessels containing the blood supply to the ovary that's often seen adjacent to it.
In this particular series, they saw it 88% of the time.
I have to be honest, I don't see it that often, but maybe we're not looking hard enough.
What's more interesting to me from this study is they had very similar results when they were looking for flow within that pedicle,
within the twisted pedicle.
When flow was present, it was viable.
When it was absent, the vast majority were dead only in one. Was it present that it was then dead in the OR?
And that's probably because again, the time just that it took for to get her to the OR.
So very similar findings as we saw in that first study that the presence of flow means viability.
And here's an example of the twisted pedicle sign right there.
Here it is on color doppler imaging, while we're still having color flow.

Now the whirlpool sign is essentially your target or twisted pedicle sign that you happen to catch on a cine clip.
And so as we're going across here from left to right, you're seeing this twisting and almost looks like a whirlpool.
And again, when they were looking at color doppler, when it's present, it's viable.
When it's absent, it's dead.
So that is really our take home here.
Here we have a woman, severe pain, nausea, the big ovary we're seeing the peripheral follicles,
a little bit of free fluid around there.
And here we have our whirlpool and twisted pedicle sign with our flow still present.

So our take home pearls is that flow suggests viability.
It does not exclude torsion.
I think two symmetric ovaries on gray scale have a very high negative predictive value.
Again, you never wanna say never it's possible, but very reassuring that torsion does not exist.
Once you have an asymmetrically enlarged ovary, whether or not you have adjacent free fluid, peripheral follicles
or a mass, you really cannot exclude torsion again, a mass of any size, particularly when the symptoms are out of proportion to the ultrasound findings.

So here's an example.
I mean, this is really not that impressive.
It's a five centimeter ovary, little bit of peripheral follicles, a little bit of free fluid arterial and venous flow.
But she was riving in pain.
And I said, you know, this degree of pain she's having does not make sense to me.
I'm more worried. And indeed she had torsion.
So when symptoms are out of proportion to what I'm seeing, I'm really, really worried.
And remember anything in the adnexa can twist.

Here was an example of a 46-year-old intermittent acute pelvic pain for a week.
She was afebrile, no discharge, we're seeing this big cystic mass kind of centrally in her pelvis.
They recommended an ultrasound, which was reasonable.
On ultrasound, we're seeing two normal ovaries, normal size symmetric.
So this isn't the ovary. Here's the big cyst centrally.
And actually I was on another service and the radiologist called me
and said, oh, you know, I think this is probably just a big tube or something, a hydrosalpinx.
And I said, wait, but she's having acute pain.
This could be tubal torsion.
And sure enough, they took her to the OR and this was isolated tubal torsion.
It's rare, but in the setting of acute symptoms like that, it's something to be considered.
And looking back at that CT that she had in the reconstructed coronal plane, what are we seeing?
A little twisted pedicle sign.
So you can even see this on CT. There it is.

Other Gynecologic Etiologies: Endometriosis and Fibroids

Okay, so our other etiologies, we're just gonna talk about briefly our endometriosis and fibroids.

Endometriosis we know is ectopic endometrial tissue affects a lot of women, 5.5 million women Symptoms are typically chronic pain and infertility.
And often, you know, we refer to these as these chocolate cysts and most common location is gonna be in the adnexa on ultrasound.
They tend to be, to me, a little bit more hypoechoic on transabdominal imaging.
And then when I go to EV, they're more hyperechoic than I expected.
With these homogeneous low level echoes, they'll have no internal flow on color Doppler imaging increased through transmission
and seeing these peripheral punctate echogenic foci are really pathognomonic for an endometrioma.
They're believed to be calcifications and little cholesterol deposits, probably from a breakdown of blood products.
Sometimes you can even see little twinkle artifact on color doppler within these calcifications.

Now, when they have acute pain with endometriosis, is either due to rupture.
So if I'm seeing what looks like an endometrioma and a little bit of free fluid next to it, they could have ruptured.
And that blood is very irritating to the peritoneal cavity.
Or sometimes you can see retrograde hemorrhage into the tube right next to it.
Or it could be due to endometrial implants within the tube as well.

So on this cine clip, I'm showing you an elongated tubular structure with those homogeneous low level echoes.
And when static notice that there's the break in the little endometrioma right there with that blood
that was just going retrograde into the tube and descending the tube, which was causing her acute pain.

Now seeing acute hemorrhage in a preexisting endometrioma will look like a little eccentric either linear
or a mass like echoes, they're hyperechoic or they can have mixed echogenicity,
but they will have no flow on a color doppler.
So seeing something right up here can be a sign that that was a acute hemorrhage and perhaps the cause of the pain.
And I understand that this can be very confusing sometimes to worry about, well, is that a mural nodule?
Is this a mucinous mucinous cystic neoplasm?
And that's really the mural nodule.
Well what you can do is bring her back because we know that hemorrhage will evolve in a rapid fashion.
So here's a 36-year-old with acute pain.
We're seeing this little eccentric nodule, but it doesn't have flow.
You can wait just two weeks and it's gonna go away.
Hemorrhage is gonna resolve very, very quickly.

Here's another example, 35, right lower quadrant pain.
And here we see this this large mass, there's actually two things going on in this right ovary.
This over here is a hemorrhagic cyst with our fibrin strands, but this other portion really looked like an endometrioma
with those echogenic, peripheral punctate echogenic foci.
But we're seeing more heterogeneity than we expect to see, right?
So we're suspecting that could be acute hemorrhage, right?
No flow in there. Bring her back.
Three weeks later, the hemorrhagic cyst has gone away, as has that acute hemorrhage.
And now it looks like a classic endometrioma.

Other things that can cause acute pain would be fibroids in the setting of prolapse of an endocervical fibroid
can actually prolapse just like a polyp.
Submucosal myomas can do the same thing. Here.
I'm showing you a big myoma that was submucosal, that's pretty much just coming out of the cervix.
And these can be excruciating, severe labor like pain because that's they're delivering this myoma, if you will.
And here we see this on our cine clip and her cervix was actually dilated to two centimeters in the cause of her pain.

But they can infarct when they get really, really large.
At first, when I was looking at this, I thought that this was the endometrial cavity that was distended with fluid.
But her endometrium you'll see is over here on the left hand side.
This was a big necrotic myoma and that was having cystic change.
So liquefactive necrosis this can happen spontaneously again when they just get too big
or bi iatrogenic as the result of uterine artery embolization or Lupron therapy that you're seeing right there.
And sometimes it can be very, very cystic change as well, but they can twist the subserosal ones in particular.

Here we have a fibroid uterus and we've got a big solid mass that we're seeing the little neck here.
Our ovary is over to the side.
So this is not a solid ovarian mass.
This is a large subserosal myoma.
And in the setting of acute pain, again, you must raise the concern for a twisted fibroid that can also occur in the broad ligaments.

So here's a 28-year-old acute right lower quadrant pain.
We're seeing a normal ovary on this side in her uterus.
We're seeing a little submucosal myoma, that little heterogeneous mass with the Venetian blind shadowing.
And over in her adnexa, she had a solid mass acute pain.
She was riving in pain.
And as we were going and putting the probe over there, we knew exactly right when we were over this mass was
when she was saying ow.
And this turned out to be a twisted broad ligament myoma and when she went to the OR.

So that pretty much sums up our gynecologic etiologies.

Non-Gynecologic Etiologies

I'm just gonna talk a little bit about our non gynecologic, and particularly appendicitis, which accounts for about 28% of cases of acute abdominal pain.
Typically they'll have an elevated white blood cell count or a c-reactive protein symptoms are anorexia, nausea,
vomiting, rebound tenderness, and particularly tenderness at McBurney's point.

So what is McBurney's point if you recall?
That starts as per umbilical pain.
It radiates down here.
If you happen to measure from the iliac crest to the umbilicus, it's about a third of the way in is
where McBurney's point and the appendix should live.

So we wanna use for transducers, I wanna get as wide of a footprint as possible.
So I have a big field of view.
So a linear would be preferable.
And start with the highest frequency transducer.
You can, even if it's a big patient, I always say don't start with the highest one.
You can come down on your frequency, switch to a lower frequency transducer if needed,
but try the highest frequency transducer that you have.
I ask the patient to point with one finger to their point of maximal tenderness.
I identify my anatomical landmarks use gentle graded compression, right?
Remember, these patients are in pain.
If you apply too much pressure right away, they'll jump off the table and then just be guarding and won't let you compress.
So very gentle compression.
And I give it the five minute rule because pretty much I don't think I've ever found a positive one that took me more than five minutes to find.
Usually it's very apparent pops right into field of view within the first couple minutes.
And if I'm searching around more than that again when I'm in the right location,
then it's usually not gonna be very helpful.

So let's review these landmarks.
You're probably more familiar with what it looks like on CT.
So I'm showing you a CT of the right lower quadrant on the left hand side of the image.
And on the right side, just a schematic diagram, we've got our spine and our iliac crest, our psoas
and we're gonna be looking at a rectangle.
Our posterior boundary is the iliopsoas muscle.
The anterior is the rectus muscle.
Our medial wall is gonna be the internal iliac artery and vein.
And our lateral landmark is going to be the cecum.
If you draw a rectangle right in there, that is where the appendix should live.

So this is a ultrasound image again, with those landmarks, there's our iliac crest.
So there's our iliopsoas rectus our vessels and our cecum.
And right here is where that rectangle should live.
We put the probe on the patient, we compress down.
And in a normal patient without an appendicitis, you will note the rectus muscle will almost touch the iliopsoas muscle.
And all that bowel here will just compress away and you'll see peristalsing bowel and everything will compress away.
Whereas when you have appendicitis, you won't be able to compress that structure
and you will see a non-compressible dilated tubular structure.

So normal appendix bowel, wall signature, five layers, alternating hypo and hyperechoic lines.
Very unusual to see.
I think this is my only normal appendix and it was actually from a colleague.
Usually I'd say when it's normal, you don't even see the appendix.
But here's the blind ending tip.
And most appendices, if you measure them in the longitudinal plane from anterior to posterior, they're gonna be less than six millimeters.

So on with appendicitis, you're gonna see a thickened appendix with the AP dimension equal to or greater than six millimeters,
that carries both a positive and negative predictive value of about 98%.
Non-compressible, non peristalsing ultrasound sensitivity has been reported to the literature to be somewhere between 86 and 96% for the diagnosis of appendicitis.
But again, I really think is, it's so operator dependent, it takes some experience in order to do this.

So here's an example of a 13-year-old female with right lower quadrant pain.
And it came to us as rule out ovarian or appendicitis.
And there we have our almost nine millimeter tubular structure.
There's some peripheral flow there.
It is in transverse, which there are some other features you can see occasionally you'll see increased vascularity.
So I do try putting on color doppler, but an appendicolith will be seen third of the time there's our shadowing little stone in there.
And seeing a peri appendiceal inflamed fat, I'm often gonna see that a lot of this echogenic fat surrounding the appendix right there
is another secondary finding of acute appendicitis.

Appendicitis in Pregnancy

Now what about appendicitis in pregnancy?
We know this is probably one of the major indications for surgery in pregnancy, occurs in about one in 1500 pregnancies
and can be very difficult to clinically diagnose.
They're reported to have about a 25% perforation rate with pregnancy, again, just 'cause it's so difficult.

There was this early study, judge study of 12 suspected cases,
where they had a mean gestational age of 17 weeks with three surgical proven appendicitis that had both ultrasound and MRI.
Of those 12 cases, there was only one true positive on ultrasound.
The remainder were not seen at all, whereas all three cases that were proven positive were accurately diagnosed on MRI.

Here's another slightly larger study of 51 cases out of Beth Israel.
Their mean gestational age was about 20 weeks, but it did range from very early to term.
Where they're using this oral gastro mark or gadolinium mix what will look, which will look dark on both T one or T two.
So the normal appendix they said their criteria were less than or equal to six millimeters.
And the appendix either filled with air contrast or both.
They had four cases out of those 51 suspected.
And there was a range from three weeks gestational age to 20 all the way up to 31 weeks.
Again, MR was diagnostic and positive in all four cases.
They did have three inconclusive results, two of which weren't seen, and one which was at six to seven millimeters.
But a sensitivity a hundred percent specificity, almost 94%.
And these are some of their examples from that article in radiology where again,
they're showing a normal appendix filled with air or that contrast.
And here's the abnormal or the positive appendices that were not filled with either and are big or dilated.
And you can argue here again, there's some of that inflamed peri appendiceal fat on this lower image.

Now here's some of our images.
They're not as pretty, but this is what we have.
This was a true negative that we're having over here, a very small appendix.
And this though it was filling with the contrast.
We saw this little echogenic or filling defect right here and it measured large
and a very large appendix over here.
And those were both true positives.

But you know, you may not have MRI accessible and for us at least, it's much more difficult
to bring the MRI tech in in the middle of the night and get everything revved up.
So we usually still try with ultrasound.
You just never know what you're gonna see.
This woman was only eight weeks pregnant.
It came to us as a rule out torsion and while we were looking at her ovary over here again,
finding that cornual portion of her uterus, there's her broad ligament where the tube and vessels will live.
There's her ovary and all of a sudden there was a little mass here next to the ovary and we were questioning what that was.
There was a little bit of flow as we turned on it.
There was a very low lying appendix and a positive appendicitis.
So you never know what you might see again, we usually try with ultrasound first for UIs,
but we know a lot of the time we're going to non-contrast CT.

Ureteral Stones

Remember we used to make this diagnosis with ultrasound all the time.
A lot of these stones, 75 to 80%, will obstruct at the UVJ
and if you fill the urinary bladder, if you have a full urinary bladder, you will be able
to see the UVJ quite well and be able to find these calculi.

So here was a patient with unfortunate stone at both UVJs that we're seeing shadowing right here,
but in the longitudinal, kinda a para sagittal plane.
Again, if you distend the bladder, you will usually see some urine in that distal ureter.
And there we have our stone right there.
Jets I'll say are inconclusive.
And here's an example of a jet with a stone.
All it means is it is a not completely obstructive stone that we know non-contrast is a little bit more helpful.
Again, we will try. So here's a 34-year-old woman.
She had right lower quadrant pain and a history of ureteral stones in the past.
And on transverse imaging note where you have those little indentations of where the trigone is
and where the distal UVJs are coming in, right there and there, there's the right and the left as we go trans longitudinally.
So kind of sagittal, and I'm sweeping through there, right here, I'm gonna hone you.
There was the little stone right in the UVJ and if we weren't looking in the area,
we never would've found it and we were able to save her the CT.

Bowel Conditions

Now though we know ultrasound isn't really good for bowel conditions and should be further evaluated with CT,
sometimes you're looking for a gynecologic etiology.
And when you see these thick walled bowel structures, you can suggest that bowel pathology is likely,
you know, what is the cause of her pain?
This could be due to inflammatory bowel disease, ischemia, infection, diverticulitis.

So I think we've covered most of the etiologies.
Just always remember this is the differential in a non-pregnant woman.
And if any woman who can get pregnant may be pregnant.

So here is a 29-year-old, one year postpartum.
She had pelvic pain.
She had a negative urine pregnancy test twice, and also a negative serum test in the emergency room.
So they thought, well, she's not pregnant, we're gonna send her for CT.
And in her uterus we see it's distended with fluid and this vascular material.
And she's got these big ovaries bilateral.
And we're saying, well those are big corpus luteum cysts.
This is gestational trophoblastic disease. Right?
That's what I would be thinking they said, but her beta's negative, they can't be.
So they send her for ultrasound.
We're seeing our classic bunch of grapes.
We're seeing our big thecal lutein cysts bilaterally.
And we say, this is gestational trophoblastic disease.
And they're like, well, I can't be her.
Her beta was negative.
And I remember seeing at a lecture once, which really saved me in this case when I said, ah,
sometimes when the beta is just so high, it'll trip up the test and it doesn't know how to record it.
And it'll actually read as is negative as zero.
So what they have to do is dilute it.
They have to try titrate it down.
And when they did, her beta was 1.4 million.
And yes, this was gestational trophoblastic disease.

This was a 39-year-old incarcerated woman.
So she's in jail, acute pelvic pain.
She said, there's no way I can be pregnant.
They throw her in the scanner and lo and behold, there's her ruptured ectopic pregnancy.
So yeah, the guards were being questioned that night.

Value of a Normal Pelvic Ultrasound

Okay, value of a normal pelvic ultrasound and the setting of acute pain.
This was a study of 86 patients with acute pain, negative ultrasound findings
and about they had follow up between six and 21 months.
86% of them had resolution of their symptoms without further evaluation or treatment.
The 14% that went on to additional imaging all had CT one had diverticulitis.
The remaining were all negative.
So just showing there is quite a good negative predictive value in this setting when we don't see anything on ultrasound.

Conclusion

And that concludes the lecture for today.
I hope that this is helpful in your practice.