Sonographic Evaluation of Ovarian Torsion - SD

Introduction

Hello, my name is Dr. Leslie Scout, and I am chief of ultrasound at Yale New Haven Hospital and Professor of Diagnostic Radiology at Yale University School of Medicine.

I am here today to talk to you about ultrasound evaluation of ovarian torsion, as well as some of the common clinical mimics of ovarian torsion.

Objectives

Today we are going to be talking about the sonographic evaluation of ovarian torsion.

The objectives of this lecture are to describe the clinical presentation of ovarian torsion, to discuss the most common gray scale ultrasound appearances of ovarian torsion, and to describe the role of doppler ultrasound in the evaluation of patients presenting with clinically suspected ovarian torsion.

In addition, at the end of the presentation, I am going to describe the ultrasound findings of common gynecologic clinical mimics of ovarian torsion, in particular, hemorrhagic and ruptured ovarian cysts, as well as pelvic inflammatory disease.

Ovarian Torsion Overview

Ovarian torsion accounts for only approximately 3% of all gynecologic emergencies.

It can involve the ovary alone or the fallopian tube alone, or most commonly involves both.

And if it is not surgically relieved, ovarian torsion will ultimately result in ovarian necrosis.

Patients therefore go to surgery when the diagnosis is made and if the ovary is necrotic, ectomy is performed.

If clinically when they are in the operating room, they determine that the ovary is likely to be viable, they can attempt to do detour as well as cystectomy if there is an underlying mass present.

Unfortunately, however, the ovarian salvage rate is low because it is extremely hard to predict as you are looking at the ovary, whether or not it is going to be viable if a detour procedure is performed.

Clinical Presentation

Patients with ovarian torsion are typically women of reproductive age who present with acute onset of severe pelvic pain, which is more common actually on the right.

Patients tend to be afebrile and they have a normal white blood cell count, although occasionally one can see mild leukocytosis.

And when patients present with this classical presentation, workup proceeds with immediate doppler ultrasound evaluation, and the diagnosis is quickly made.

However, there are very common atypical presentations, which you should be aware of.

And first of all, although ovarian torsion most commonly occurs in women of reproductive age, it can actually occur in postmenopausal women and children as well as neonates.

And in children ovarian torsion often presents as an abdominal or pelvic mass rather than acute onset of pelvic pain.

In addition, another common atypical presentation is that the pain rather than being sudden severe and acute may actually be relatively mild or intermittent.

And in some series, in fact, this intermittent or mild presentation of very minimal pelvic pain has been reported in as many as 50% of cases.

And in these patients, these symptoms may mimic GI renal or other GYN pathology.

And because of this clinical overlap, often a CT scan is a first imaging modality that is obtained rather than an ultrasound.

Risk Factors

What are the risk factors for ovarian torsion?

The most common risk factor is the presence of an ipsilateral adnexal mass.

About 20% of cases occur in women who are pregnant, particularly women who have ovarian hyperstimulation syndrome.

Pelvic surgery can predisposed to torsion, particularly in patients who have undergone tubal ligation.

In addition, in children occasionally lack supporting ovarian ligaments or believed to be the predisposing factor where that can result in ovarian torsion.

As I mentioned, it is an underlying ovarian mass that is the most common risk factor, and it is estimated that patients have such a mass in about 50 to 80% of all cases.

The most common is a dermoid cyst or cystic teratoma of the ovary.

But of all adnexal masses, it is the parat tubal cyst itself, which is most prone to torsion.

Although a peric tubal cyst is less common than dermoids in the general population.

Simple cysts and hemorrhagic cysts can also predispose to torsion.

And very rarely arian cancer can predispose detorsion any mass.

Though once it causes the aex, it would be greater than five centimeters in dimension predisposes the ovary detorsion.

Interestingly though, this is not true in children, presumably because their pelvis is small, and if a mass is very large, greater than five centimeters, it is more likely fixed in place and therefore less likely to rotate along its pedicle.

And similarly, in adults, ovarian masses that are extremely large, greater than 12 or 15 centimeters in diameter, again, are less likely to tors because they are fixed within the pelvis and unable to rotate.

In terms of children who have normal ovaries and end up with ovarian torsion, this is believed to be due to some type of laxity in the pelvis, either lax supporting ligaments, sometimes due to redundant Mesos banks, sometimes possibly tubal spasm.

And in addition, ovarian torsion in children has been described when there is abrupt change in intraabdominal pressure because of coughing, vomiting, and sometimes even strenuous exercise.

Ultrasound Evaluation

If a patient is suspected of ovarian torsion, doppler ultrasound should be the first imaging modality that is performed, and it is the gray scale features on ultrasound examination that really are the most important for making this diagnosis.

That being said, the appearance of ovarian torsion on gray scale imaging is still quite variable and likely depends on the time since torsion occurred, as well as the degree of torsion.

The findings that you want to look for though on gray scale imaging are first and foremost the presence of an enlarged ovary.

As yet, I have never seen an ovary that is normal in size, which has undergone torsion, and maybe someday I will, but so far every case of ovarian torsion I have seen the ovary has been enlarged.

The central ovarian stroma tends to be very heterogeneous with hypo coic areas due to edema and echogenic areas due to hemorrhagic infarction.

And this infiltration of the central stroma tends to displace the follicles in the ovary peripherally.

And so one sees a characteristic pattern of peripheral location of small follicular cysts.

However, if torsion has been present for a relatively long time, the ovary can be quite amorphous in appearance.

Another thing you can look for is in atypical midline position of the ovary.

Always check to see if there is an underlying ovarian or adnexal mass.

As I mentioned, you will see this in up to 50 to 80% of all cases.

If a cyst is present, look for asymmetric sick thickening of the cyst wall and also be very careful to try and identify the tube which is usually between the ovary and the uterus, because often you can see the tube or the pedicle is dilated or emus.

And if you look at it in cross-section, you can see a target sign that looks like a archery target.

In addition, it is very common to see a small amount of adjacent free fluid when the ovary undergoes torsion.

The initial thing that happens as the pedicle twists is that the lymphatics are obstructed.

And during this early time blood flow may be normal, but lymphatic obstruction actually is what causes the ovary initially to enlarge and to become emus.

As the obstruction persists, one sees decreased throw through the decreased flow through the pedicle, then one will see reversed diastolic flow.

This is followed by decreasing or absence of venous flow, and only after the pedicle has been torqued for a fairly substantial period of time will you see complete absence of arterial flow.

So given this progression of pathologic findings over time, it is not surprising that the doppler characteristics or doppler findings of ovarian torsion are quite variable.

And again, this is mostly due to differences or variability in the length of time from torsion to imaging and also to the degree of torsion.

But in addition, there are two arteries that supply blood flow to the ovary, one from the uterus as well as one from the aorta or iliac vessels.

And since one of these can TAUs and not the other, this can sometimes preserve flow to the ovary.

Another thing that can affect the Doppler findings is that ovarian torsion in women is very frequently intermittent.

And so you can be seen the torsion during a time of detour when blood flow has been restored to the ovary.

Diagnostic Ultrasound Findings

So what then though, are the diagnostic ultrasound findings of ovarian torsion?

Well, certainly if there is complete absence of arterial flow, this is consistent with the diagnosis of torsion.

And another thing that you can look for is the doppler equivalent of the target sign and the twisted pedicle, which has been termed the Whirlpool sign.

And I will show you some cases of this in a few minutes, but it is very important to recognize that while those two features absence of arterial flow and the presence of the color Doppler Whirlpool sign are diagnostic of ovarian torsion, a normal Doppler ultrasound examination does not exclude this diagnosis.

As I said, you can have, if you consider absence of arterial flow as being the most important diagnostic criteria for ovarian torsion, you will have a considerable number of false negative exams because flow may be present early on, but you can also have false positive exams.

And this can be due to sampling error, the fact that you may not see flow in a normal ovary, particularly in a post-menopausal woman or in a woman where the ovary is deep within the pelvis.

And also if through inexperience, your machine settings are faulty or not very sensitive.

Case Examples

Let's go through some examples of ovarian torsion that point out these findings that I have just described.

As I said, the squon of ovarian torsion and gray scale imaging is the presence of an enlarged ovary.

And so here you see an example of an ovary, which is quite enlarged, almost six centimeters in diameter.

You can see that the central stroma is heterogeneous with hypoechoic areas representing edema and more echogenic areas representing hemorrhagic infarction.

You see the peripheral displacement of small follicles, some adjacent free fluid, as well as a simple cyst and a hemorrhagic cyst, which are underlying masses, possibly the lead points causing this ovarian torsion.

Here is another example.

You see a very enlarged ovary.

Sometimes there are very few number of peripherally displaced cysts that's very amorphous, heterogeneous, central stroma, and a very large simple cyst, which was the lead point for this torsion.

Here is another example where you can see an abnormal position of the ovary.

Notice that it is in on the transabdominal image.

It is midline in the pelvis anterior to the uterus.

Here note the intrauterine deis, which is abnormal in location, and within the cervix rather than in the fundus where it belongs.

Note again, the lead point.

This large simple cyst with some reverberation artifact anteriorly.

And when you do the endo vaginal exam, you can see that the right and left ovary are adjacent to each other.

You can see marked asymmetry in the size with the ovary that has undergone torsion quite a bit larger than the normal ovary.

Here again, the lead point, the central amorphous heterogeneous stroma with peripheral displacement of small follicles.

And another example, again in enlarged ovary, over six centimeters in diameter, peripheral displacement of follicles adjacent free fluid.

And in this particular case, you can see a hemorrhagic cyst, which was the lead point for the ovarian tors.

As I said, it is really critical to try and identify the pedicle, and usually you can find the pedicle between the ovary and the uterus.

And if it is Taurus, it will become extremely emus, as you can see in this case, nicely outlined by some adjacent free fluid.

And if you look carefully across section, it has a bullseye or target appearance, just like an archery target with alternating rings of decreased echogenicity and more echogenic circular structures.

And this has been termed the target sign and again, often seen between the tors ovary and the uterus.

Here is the adjacent normal ovary.

Here is the very large Tors ovary and the target sign.

If you see a cyst and the patient is presenting with acute pain, look at the wall of the cyst.

And if you see asymmetric thickening, again, consider the diagnosis of ovarian torsion.

And those are the gray scale features, which in my personal experience you tend to see in the vast majority of patients with ovarian torsion.

Doppler Examples

How about the Doppler examination?

Let me show you some classic examples, in which Doppler is very helpful.

And the squon, again, is complete absence of arterial and venous flow.

So here you have a classic appearance on gray scale of a tourist ovary, enlarged peripheral displacement of follicle.

It is adjacent free fluid heterogeneous stroma, and with color doppler, no evidence of blood flow.

Remember that your spectral doppler is of course more sensitive to blood flow than color doppler, as is power doppler.

So use both of those modalities to look for flow.

And again, this the, they confirm that there is absolutely no evidence of flow within this ovary, and this again confirms the diagnosis of ovarian torsion.

But I caution you when the ovary is this classic an appearance for ovarian torsion, I do not really care what the Doppler findings show because the gray scale findings are enough to make the diagnosis.

Here is another example though, where the Doppler confirmed the gray scale finding again, classic appearance of ovarian torsion and gray male, but on color and spectral doppler, no evidence of blood flow.

Just a little bit of noise within the ovarian parenchyma.

This is a child who presented with a palpable abdominal mass.

You can see the bladder here in the uterus in this extremely large mass with no evidence of blood flow on Doppler examination.

And they were concerned about ovarian torsion because they figured any kind of malignancy that was this large would be likely to have flow.

And so because they considered the diagnosis of torsion, they did a very interesting thing.

They changed transducers and used a high resolution linear array transducer.

They understood that they would not be able to see the entire mass, but they could see the better advantage, the more superficial anterior portion.

And note that they can, again, with this high resolution technique, see the peripherally displaced tiny follicles.

And this helped confirm their diagnosis that this mass indeed represented ovarian torsion rather than some kind of malignancy.

This is the same case that I showed you earlier where you could see that target sign on the gray scale imaging.

And if you put color flow on that area, you will see the vessel swirling around.

And this has been described the Whirlpool sign.

And if you see this finding, this is a very specific finding for ovarian torsion, but unfortunately it is a very uncommon thing to see, and I have only seen it once or twice in my practice, which is why I have gone to the literature to show you some other examples.

And here is from the paper that initially reported this from India, where you can see the target sign, the hypo coic, echogenic hypo coic echogenic alternating rims on the gray scale, and the swirling vessels on the color doppler, indicative of both the target and the whirlpool sign.

And this is a third example led to me by a colleague from Johns Hopkins University, again, on gray scale, classic appearance of a enlarged tourist ovary, the target sign on the gray scale on this whirling vessels creating the whirlpool sign on the color Doppler image.

But as I mentioned, the Doppler findings can be somewhat variable, again, mostly due to the fact that torsion can be intermittent and variability in the length of time and degree of torsion from onset until imaging with ultrasound.

And so here is an example of a patient who has got the classic gray scale features of ovarian torsion.

The simple cyst is the lead point, note the peripherally displaced follicles.

But when we put colored and pulse doppler on, notice that there is some arterial flow, though it is abnormal as there is a high resistance waveform pattern with absence of diastolic flow.

And again, although there is blood flow, it is abnormal, but it is the gray scale findings alone that cause you to make with confidence the diagnosis of ovarian torsion.

If you have a question about it, you can consider doing an MRI as was done in this case.

This was early in our experience.

And you can see again, the ovaries enlarged the follicles are displaced peripherally.

Here is the simple cyst as a lead point.

And notice this high signal intensity, central ovarian stroma consistent with edema.

Again, all the findings that you see on the ultrasound you see on the mr

here is another example of a patient who presented with intermittent pelvic pain.

Note this ovary is huge eight centimeters in diameter.

Again, the classic findings of ovarian torsion.

But when we look with color and spectral doppler, there is both arterial as well as venous flow.

However, I want to caution you that the presence of this blood flow should not make you should not dissuade you from considering the diagnosis.

Ovarian torsion. All this may mean is that the ovary is in fact viable.

So again, when the gray scale findings are classic in appearance, I really do not care what the doppler looks like.

I am going to make the diagnosis whether I see blood flow or not.

And this is the case I showed you at the outset, again, the classic gray scale findings of ovarian torsion.

But on the Doppler exam, on color, there is arterial and venous flow confirmed on the spectral examination.

Again, this should not dissuade you from making the diagnosis.

In fact, this patient should go to the operating room quickly because there is a good chance that the ovary will be viable when they detour it and therefore will be salvageable.

Another example demonstrating blood flow arterial and venous in a patient with a classic gray scale features of ovarian torsion.

Pitfalls in Diagnosis

What are some of the pitfalls in the diagnosis of ovarian torsion?

It can be difficult when you have a cyst that is possibly hemorrhagic or ruptured to determine if the pain is due to symptoms from the cyst itself or due to torsion, since you know that the cysts also can predispose to ovarian torsion.

So this is an example, again, early in our experience where a patient came into the emergency room with acute onset of pain.

This ultrasound was done, a cyst was seen, some adjacent free fluid arterial and venous flow was identified.

And because blood flow was seen, they thought that they should exclude the diagnosis ovarian torsion.

And they thought that the pain was likely to do to leakage from the cyst.

But notice that if you look carefully at the rest of the normal OV ovary, you do not see any normal ovarian architecture.

There is some tiny peripherally displaced cyst.

There is a very heterogeneous central ovarian stroma.

So unfortunately in this case, there are the classic gray scale features of ovarian torsion.

But the inexperienced resident was dissuaded from making this diagnosis because of the presence of blood flow.

This patient came back to the emergency room three days later, noticed that now the ovary is even larger, that cyst is smaller.

There is much more echogenic heterogeneity within that ovarian str consistent with hemorrhagic infarction.

And unfortunately, when they went to the operating room at this time, the ovary was infarcted and this woman did lose her ovary.

So again, do not let the presence of blood flow dissuade you from making the diagnosis.

If the gray scale features are classic, this is a patient who had ovarian hyperstimulation syndrome and had just become pregnant.

And notice that her right ovary and her left ovary are extremely large.

There are numerous cysts throughout both ovaries consistent with the diagnosis, ovarian hyper stimulation syndrome.

And when we did the doppler, you can see that there was arterial flow to both ovaries.

However, on this particular patient, the left ovary was much more tender than the right, even though it looked very similar.

And it was tender on examination so that when the probe was on the left side of the pelvis, the patient was much more uncomfortable than the right.

So because of these changes in physical examination, and because we know of the risk of ovarian torsion in women with hyperstimulation syndrome, this patient did go to the operating room and indeed the left ovary had been tourist and they were able to salvage it.

The only clue, perhaps retrospectively on evaluating or analyzing the Doppler waveform spectrum is that there is a little less diastolic flow on the left than on the right, possibly indicating increased peripheral vascular resistance due to swelling from the ovarian torsion.

Another pitfall in the ultrasound of diagnosis, ovarian torsion is the patient who has chronic torsion.

And when the ovary has been infarcted for a while, it becomes extremely amorphous.

And sometimes all you see is just a big sack of blood.

Notice the low level echoes within the cystic mass in the left a nexa or in this case where you see, again, a big cystic mass just so with some clot within it.

And so it can have a very variable appearance.

When the torsion has been longstanding, it is most common that either the ovary itself or the ovary and the tube TAUs, but occasionally, particularly in children, it is possible to tors just the fallopian tube.

And this can be very difficult to make this diagnosis.

But here is a patient who presented with acute pain.

The ovary look normal, and you have no trouble making the diagnosis of hydrocele pinks in on the right a nexa.

But notice that the hydro cell pinks form sort of a beak point here, just as if you were to take a balloon and twist it, making a balloon animal at a children's birthday party.

This beak sign is not a typical feature of a dilated fallopian tube, which tends to be more dilated actually at the fibrillated, and rather than narrowed and pointed as you see here.

And so when you see the big sign in a patient who presents with acute pain, consider the diagnosis of torsion that is isolated to the fallopian tube.

And here is another example of a patient showing that big sign in whom just the fallopian tube alone had undergone a torsion, and the ovary was normal.

As I mentioned, it is a dermoid cyst that is the most common lead point in a patient with ovarian torsion.

And it can be very difficult to make the diagnosis of a tors dermoid, particularly when it is large.

You may not see any of the classic ultrasound features of ovarian torsion because you do not see the normal ovary.

So you cannot recognize those changes in the ovarian stroma or the displacement of the peripheral follicles.

So in my recommendation in terms of dealing with this clinical situation, if you see a patient with a large dermoid, you cannot see the ovary to assess the parenchyma.

And if that dermoid hurts, you have to assume that it is either tourist or it is leaking.

In either case, it is a surgical situation.

And you should advise the clinicians that you cannot exclude torsion or rupture of the dermoid.

You can try using a color, but it does not really help because often you do not see any blood flow in a dermoid cyst.

And as I mentioned, even if you do do see blood flow, this does not exclude the diagnosis.

So in general, if the dermoid is symptomatic and large and you cannot see the ovary, you have to be concerned about the possibility of torsion.

What about the patient in whom you have some clinical suspicion and you have some suspicion on the ultrasound findings, but they are not totally classic, they are somewhat equivocal.

This is the time when I think Mr is very helpful as a problem solver.

So this is a patient who had very mild pain, had been intermittent over several months.

When we did the endo vaginal exam, we can see that there is some asymmetry in the size of the ovaries.

The right ovary was just over five centimeters.

The left three and a half right ovary, therefore clearly bigger.

Again, some peripheral displacement of follicles, but you can see that on the normal left ovary as well.

And the central s stroma a little bit more prominent.

This patient did have arterial flow and venous flow, which I have not shown you, but there was asymmetry in the size of the ovaries.

But because it was not that dramatic and the patient's symptoms were not that dramatic, we were not really sure if this was a torsion or not.

And in this case, we ended up recommending that they do an mr.

And MR is very useful as a problem solver.

That being said, it actually shows you very similar things to what I have described on the ultrasound examination.

The ovary that is tors on MR is going to be enlarged.

It is going to be abnormal in location.

Note, this midline position.

There is going to be a high signal intensity central stroma due to edema, and you will see peripheral displacement of follicles.

One thing that you can do with MR that you cannot do with ultrasound easily in the United States since intravenous ultrasound contrast is not yet FDA approved, is you can give intravenous contrast.

And with intravenous contrast, you will see that there is lack of contrast enhancement and sometimes that can help you identify also the thickened fallopian tube, which in this case was a little bit hard to differentiate from the ovary until we gave the contrast.

Here is another example.

This is a pediatric patient in which the ultrasound was not diagnostic and they did not have a good explanation for the patient's pain.

And on the mr you can see the findings of ovarian torsion here is the hemorrhagic cyst and a serous cyst, either one of which could have been the lead point.

You can see increased signal consistent with edema in the residual ovarian parenchyma, peripheral displacement of little follicles.

And you see this round swirling mass between the ovary and the uterus representing the twisted thickened pedicle and following contrast enhancement, no enhancement in the ovary, and just a little bit of enhancement in that pedicle in this placement with patient with ovarian torsion.

MRI and CT Findings

I want to spend just a few minutes talking about the appearance of ovarian torsion on CT scan, even though this is an ultrasound lecture.

And the reason for that is that in these patients with atypical presentation who present with mild or intermittent symptoms that mimic GI or renal or even other gynecologic pathology, sometimes a CT scan may be the first imaging test that is obtained.

And so it is important that one be able to recognize the appearance of ovarian torsion on ct.

And just like on Mr, the Ultra, the appearances of ovarian torsion on CT mimic exactly what I have described on ultrasound.

So you see an enlarged midline ovary, peripheral cysts and a thickened adjacent pedicle, as well as a heterogeneous central ovarian stroma, sometimes increased in attenuation due to hematoma, areas of decreased attenuation due to edema.

Another example went to me by Dr.

Loff now at the University of Pennsylvania, where you can see again these peripheral follicles, this thickened adjacent fallopian tube and stranding in the pelvic fat, which is a non-specific finding on CT of inflammation or infection.

Another example from Dr.

Loff showing the lead point, this simple cyst here with a star, the underlying mass, as well as this thickened fallopian tube between the ovary and the uterine cornea.

And on ct, just like with Mr, you can give intravenous contrast.

Notice, there is no enhancement of this torstin infarcted ovary notice, just like on ultrasound, you can see some adjacent free fluid sometimes of high attenuation indicating pelvic hematoma.

Those are a brief summary of the ultrasound, CT and Mr appearances ovarian torsion.

But as you evaluate these symptomatic patients, it is also important to differentiate ovarian torsion from other common causes of acute pelvic pain in the woman of reproductive age.

And the three things that I want to talk about at the end of this lecture are hemorrhagic cysts, ruptured ovarian cysts, as well as pelvic inflammatory disease.

Common Mimics

Hemorrhagic Cysts

And if you take women of reproductive age, all women who come to the emergency room or who present with acute pelvic pain, actually hemorrhagic cysts are the most common cause of acute pelvic pain in these women.

And so it is very important to recognize the ultrasound findings to make this diagnosis with confidence.

Patients with hemorrhagic cysts, these hemorrhagic cysts may have a variable pattern of internal echogenicity, but one of the key features as this pattern will change and evolve over time.

These are cysts, so the wall should be thin and regular, although it may be vascular.

Because they are cysts, they will demonstrate increased through transmission.

And no matter what the pattern of internal echogenicity, there should be no evidence of internal vascularity when a patient presents to the emergency room acutely within the first several hours of a hemorrhage into an ovarian cyst.

The typical pattern that you see is, as I have presented here, one of diffuse homogeneous low level echoes here is a cyst then wall, some increased through transmission and diffuse low level echoes in a homogeneous pattern throughout the hemorrhagic cyst as time moves on.

What happens is, is that the red blood cells lice and they release their contents into the cystic fluid and fibrin strands form.

And these can form a lace like or spider web, sometimes people call it as a fishnet pattern of internal echoes and septations.

And they can be sort of minimal as you see on the example on your left, where they can be more echogenic and more confluent as on the example on your right.

And over time, they tend to coalesce to form the clot.

So they tend to point towards a particular focus, often associated with the wall because the clot is often adherent to the wall.

And the next thing that happens is that these septations, as I said, evolve into acute clot.

And this clot acutely tends to be echogenic.

Most often it is adherent to the wall.

It can be kind of polypoid and configuration as you see here, but sometimes that echogenic clot can actually be suspended within the cyst.

And this really does look like a spider web with maybe some of kind of a fly or bug caught in the fibrin strands within this hemorrhagic cyst.

Over time, that clot is going to change, and the fluid within it is going to be absorbed and it is going to become retractile.

And this can be diagnosed on ultrasound by the identification of the sharp or concave margins.

And this is very typical for retractile clot and is very uncommon to see with any kind of soft tissue mass.

Here are two other examples showing these concaved scalloped margins, very straight margins.

This would be very atypical for any kind of soft tissue component or neoplasm.

And here again, a very straight margin, very unlikely that any neoplasm would have that kind of a configuration.

What do you do though, if you see a patient who has got a little echogenic focus within a cyst in the ovary?

And you have to differentiate between clot and a mural nodule because if you see a mural nodule or a soft tissue component, you of course are gonna be concerned that there is an underlying cystic epithelial neoplasm.

Well, one of the first things you can do actually is to roll a patient.

And if that clot moves or layers just like sludge within the gallbladder, and here you can see a very flat interface between that hemorrhage and the rest of the fluid within the cyst, you know, this is not going to be a neuro nodule, and this is just going to be hemorrhage.

And the other thing, of course, that you are going to do is to check your vascularity with your color power as well as spectral doppler.

And if you see any blood flow, you have an answer, you know, this has to be a neoplasm or some sort of a tumor nodule.

If you do not see blood flow, it is most likely to be clot.

But you need to remember that sometimes when mural nodules from tumors are small, they may have so little blood flow that it is below the resolution of your ultrasound machine.

And so for that reason, we tend to get follow up because again, clot or internal echoes, no matter the appearance, should have no evidence of vascularity.

But because you cannot necessarily differentiate a small tumor nodule from clot, if you do not see blood flow, we do recommend getting follow up.

And the typical timeframe that we get this follow up is when in about six weeks, and again, this is very important, particularly if the clinical presentation is somewhat atypical.

In other words, the patient did not have pain and you see a hemorrhagic cyst, but there are no symptoms, or if it does not really look typical for the clot that I have shown you, you do not see those straight concave margins in six weeks.

Clot should change in appearance.

And if the echogenic focus does not change in six weeks or does not resolve, or if you see blood flow in either case, you have to consider that there is a tumor nodule there.

And it then becomes a surgical lesion.

Ruptured Ovarian Cysts

What about rupture of a cyst?

This, again, is a very common cause of pain.

And often the pain is not only acute but extremely severe.

These patients may have rebound tenderness.

If they lose a lot of blood, they may even be hypotensive.

Typically, they have a normal white blood cell count and they are afebrile.

How do you make the diagnosis of ovarian cyst rupture and ultrasound examination?

Well, first of all, it sometimes is a diagnosis of exclusion.

In other words, the ultrasound examination is completely normal.

Why is that? Well, the cyst rupture, the fluid dissipates within the pelvis is and is absorbed.

So with the cyst being ruptured, you do not see it anymore and you do not even see the adjacent fluid.

But sometimes you, the cyst does not rupture completely and it will look cremated with a pointy abnormal configuration with straight margins.

It may contain some internal debris, and you may see some fluid adjacent to the ovary or within the cul-de-sac, sometimes even in Morrison's pouch if there has been a lot of bleeding.

And sometimes you can actually see a clot within the fluid.

Look carefully for these low level echoes indicating that this is hemorrhagic fluid.

Here is an example of a patient who has a ruptured cyst.

You can see the ovary here, and the cyst is a very cremated configuration with angular margins.

And note that this ovary is surrounded by a lot of amorphous material.

And this is clot that is actually seems to almost be engulfing this ovary.

When you see this much clot.

Very important to look in the cul-de-sac.

Notice that there is a lot of clot in the cul-de-sac posterior to the uterus and in the anterior cul-de-sac anteriorly as well.

And when you see this much clot look throughout the rest of the abdomen and in the upper quadrants, in order to quantify the amount of hemoperitoneum, and here in this patient in the pelvis, you and in the flanks, you can see a huge amount of fluid surrounding these loops of bowel with a lot of low level echoes within them.

Indicative that this is hemorrhagic fluid.

Here is another example where you can see the ovary surrounded by a huge amount of clot.

There is blood flow to the ovary, so you know, there is no, so you can identify that this is ovary, but the clot has no blood flow, of course, within it.

And in this particular case, you cannot see the cyst anymore 'cause it is ruptured.

All you see is the hemoperitoneum around it.

But again, always look elsewhere in the pelvis.

And this patient had a huge clot in the cul-de-sac behind the uterus.

Here you can see it on sagittal, a lot of free fluid in the anterior cul-de-sac.

And note that there is even fluid in the upper quadrants here surrounding the spleen.

And this patient was very unstable and actually ended up getting a CT scan.

I am actually not sure why they did not just go to the operating room, but the CT scan shows just what we saw in the ultrasound.

So fluid around the liver and around the spleen, and a huge amount of fluid within the pelvis.

Some of it is showing high attenuation consistent with the active bleeding.

And this patient had to go to the operating room because she was unstable just from bleeding from her hemorrhagic cyst.

Pelvic Inflammatory Disease

And the last thing I want to mention as a relatively common cause of acute pelvic pain in women of reproductive age is pelvic inflammatory disease.

This is an ascending infection.

It begins with a cervix, and these bacteria move up through the endometrial cavity, out through the fallopian tube and into the pelvis to surround the ovaries.

And currently in the United States, chlamydia is the most common cause of pelvic inflammatory disease, in past years.

Gonorrhea of course was the most typical cause of PID in women in the United States.

But this has been supplanted now by chlamydia infection.

The clinical presentation of patients with PID can be quite variable, and the symptoms can be very minor or vague, and then can be as extreme as an acute onset of severe pain.

Unlike the patients with ovarian torsion or hemorrhagic cyst, these patients tend to be febrile.

They have an elevated white blood cell count.

They may have a purulent vaginal discharge, and we will have cervical motion tenderness on exam.

Well, in ultrasound, you do not ever see the cervicitis, so this is not a diagnosis you can make with ultrasound, but you can start to see findings once those bacteria extend into the endometrial cavity.

And the first thing that you might see is endometritis.

So what are the findings of endometritis on ultrasound?

Well, the first thing is that the endometrial stripe becomes indistinct and sometimes thickened.

So here is a sagittal view of the uterus of a woman with pelvic inflammatory disease.

I can see a little bit of fluid within the endometrial canal, but I cannot see the endometrial stripe.

I would have no idea how to measure it.

And so for me, this is a very indistinct endometrial stripe.

Now, depending upon the organism that has caused the infection, if it is a gas forming organism, you can actually see echogenic foci within the distended endometrial cavity was shadowing because of the gas.

And sometimes you can see fluid and a lot of debris distending.

The endometrial canal, endometritis is often associated with marked increased in vascularity.

And this will have an abnormal arterial waveform pattern characterized by a lot of diastolic flow, different from the normal high resistance waveform pattern in the normal uterine artery.

Now, those bugs continue on their path up through the endometrial canal and out into the fallopian tubes.

And so the next thing that develops is sal meningitis or inflammation of the fallopian tubes.

And what you see on ultrasound is a very thick inflamed fallopian tube.

It is not normal on most patients to actually even be able to identify the fallopian tube unless there is ascites in the pelvis.

So when you see the fallopian tube and it looks thick like this, you have to be concerned about inflammation.

And often it will be very vascular.

If the infection is acute, the fallopian tube will become obstructed, and then it becomes filled with pus and debris.

So you can see a lot of fluid in this markedly distended, tubular serpiginous fallopian tube.

Again, the debris, the low level echoes representing pus and also the wall, again, often very vascular.

If this is acute, sometimes that pus and debris will layer as you see in this very distended, serpiginous fallopian tube.

And it is in patients with chronic PID sometimes you do not see as much puss in the tube.

And so it is important that you know how to identify a fallopian tube and differentiate that from other cystic structures in the nexa.

And three things to think about.

One is the waist sign, and this is a little pinching off, if you will, indentation a part of that tube.

And that occurs because that fibrillated end is typically more dilated than the rest of the fallopian tube.

Another thing that you can look for is the coquee sign.

And this is the presence of these little nodules seen often best in cross-section.

These are just the thickened mucosal ridges or striations, which are commonly seen in the fallopian tube.

But I should caution you that you can see neural nodules like this with malignancy.

So this should not be the only sign that you use to make the diagnosis of a hydro or a psal things.

And the last thing that you should look for, which is considered really the most specific thing, again, if you go back to that analogy that I mentioned earlier of the balloon animal, if you think of the fallopian tube as a big long balloon and you fold it on itself, you see these incomplete septation signs, which is just the two walls of part of the tube as it folds on itself.

So anytime you see a septation that does not extend from one side of a cystic area to the other, think of a fallopian tube that is just folded upon itself.

As the pus exits from the fibrillated end of the fallopian tube, it spills into the peritoneal cavity and it may coat the surface of the uterus causing this hypoechoic rim around the uterus.

And this is what you see in patients who have uterine sitis.

And this can form adhesions.

And so sometimes you can see that the rectum, or in this case the ovary, is attached to the uterus.

And instead of the normal acute angles that you see between the ovary and the uterine fundus, you can see these straight margins due to this hypo coic p***y substance again causing adhesions between the serosal surface of the uterus and the ovary.

And the last thing that will happen is that all of this infection and inflammation will engulf the ovaries and the patient will develop tub ovarian abscesses.

And these are typically complex multilocular, thick walled masses containing variable patterns of internal echoes.

Again, often bilateral ovaries often seen together in the cul-de-sac or anterior to the uterus.

Another example showing very complex vascular bilateral nexo masses.

Here you can see the distended fallopian tube and these low level echoes within the cystic uh, components.

These masses tend to be tender and tend to demonstrate a lot of increased vascularity, and as I said, tend to be bilateral.

And again, it is very important to talk to the patient and they will let you know if their mass is painful.

And if the mass is painful, again, think strongly of the tub ovarian abscess.

Now, when you see a complex mass in the pelvis, and it is tender, but you can actually see the ovary separately surrounded by inflammation, this is best term, not a tubo ovarian abscess, but as best described as a tubo ovarian complex.

And it is important to recognize this because if the ovary is preserved and it often is preserved a while from involvement of infection by the ovarian capsule, which is a barrier to the spread of infection, this will respond better to antibiotics.

And so often these patients deserve a trial of antibiotics before they have any kind of a drainage procedure or surgery.

And another thing that has been described recently is that the pelvic fat in patients who have inflammation or infection tends to become echogenic.

This is not a specific finding for pelvic inflammatory disease and can be seen in patients with diverticulitis or inflammatory bowel disease.

But in patients with PID, you will see this increased echogenicity of the pelvic fat around the AA and around the uterus as you see here.

And if you see this, this increases your sensitivity for making this diagnosis.

Conclusion

So in conclusion, in a patient with ovarian torsion or with clinical suspicion, I should say, of ovarian torsion, do not be dissuaded by the history.

Not all patients with ovarian torsion present with acute severe pain.

In many patients, the pain is relatively mild or intermittent.

Focus on the gray scale imaging features to make this diagnosis look for an enlarged ovary with a heterogeneous central stroma with areas of increased and decreased genicity, peripheral displacement of small follicular cyst and abnormal midline location, and look between the enlarged ovary and the uterus to find that thickened adjacent pedicle, which on cross-section might show that target sign.

When you do the Doppler examination, and we do do this in all patients, do look for absence of flow, abnormal flow in the whirlpool sign because the absence of flow in that whirlpool sign are diagnostic findings for ovarian torsion.

But do not be dissuaded by the presence of blood flow.

Do not let this keep you from making the diagnosis ovarian torsion.

If the gray scale features are classic, in fact, the presence of blood flow in a patient with ovarian torsion may be a good thing and may indicate that the ovary is salvageable.

Look for similar findings on CT and use MRI as a problem finding problem solver.

So again, on CT you will see an enlarged midline non enhancing ovary with thickened adjacent tube.

And again, Mr.

You will see the same thing though often it is a little bit easier to see the pedicle and the increased signal intensity of that central ovarian stroma.

In terms of hemorrhagic cysts, remember the key feature here is that there will be no doppler flow except in the cyst wall.

No matter what the pattern of internal echogenicity, remember to get follow up because clot will resolve or get smaller after six weeks.

And remember that if patients who have ruptured or hemorrhage occasionally, they can develop massive hemoperitoneum that requires surgery in order to stabilize them.

In terms of patients with pelvic inflammatory disease, the most common finding, of course, is a presence of a complex tender vascular and bilateral AED nexel masses.

But look carefully for some of these more subtle findings that I have described of PID, such as uterine sitis, echogenic pelvic fat, and that dilated adjacent tube, because this will increase your sensitivity for making this diagnosis.

Thank you for your attention.