Optimizing Differential Diagnoses of Pelvic Masses with 4D - SD

Introduction

I am Dr. Arthur Fleischer, chief of ultrasound at Vanderbilt University Medical Center, Nashville, Tennessee.

This presentation will cover the various sonographic techniques, including transvaginal sonography 3D color Doppler sonography, and mention the use of contrast in the evaluation of patients with pelvic masses.

This presentation will cover the application of various sonographic techniques in evaluating patients with pelvic masses.

Sonographic Techniques for Pelvic Masses

Trans abdominal sonography is used for a survey of the pelvis, and in some cases can display images better than transvaginal.

Transvaginal sonography allows us to see masses in detail.

Color doppler lets us depict the vascularity 3D evaluates the morphology and live.

3D is a new technique which allows us to see the morphology of lesions.

And I'll just mention, although it's not FDA approved the application of contrast for evaluating, patients with pelvic masses.

I'm going to emphasize the clinically important parameters in, evaluation of patients with pelvic masses.

Optimizing the use of these various techniques and give you some examples.

Clinically Important Questions

The clinically important questions are, is it benign or potentially malignant?

Is it torse? Is it persistent or transitory?

Does it require immediate surgery or medical treatment?

And if surgery is indicated, can, can it be performed laparoscopically?

And these are all questions that need to be answered with ultrasound.

Transvaginal sonography allows us to see detailed images of the adnexal structures, but color doppler adds a lot of information concerning the vascularity of the lesion and its potential malignancy.

Transabdominal provides a survey, an overview transvaginal allows us to see details.

Color doppler, as I mentioned, eval, evaluates the vascularity and the integrity of the vascularity.

3D allows us to see spatial relationships In evaluating patients with pelvic masses.

Evaluation Parameters

One needs to determine the organ of origin, whether it's uterine, ovarian, tubal, or other, such as related to bowel, whether the morphology is totally cystic complex, meaning containing cystic and solid areas or solid, whether the internal consistency is completely anti coic or fluid, whether they're septations or papillary expressives.

And finally, sonography should detect whether there's ascites, metastatic disease, or pelvic ectasis.

Evaluation of Cystic Masses

Now I'm going to de-emphasize the evaluation of cystic masses because this is relatively straightforward.

We need to determine whether it's a physiologic cyst, whether indeed is related to the ovary or outside the ovary, such as para ovarian cysts, and realize that some completely cystic masses can in fact be epithelial tumors.

This netter diagram shows the, group of cystic lesions that we can study using sonography.

And depending on where the ovulatory disorder occurs, we can have a follicular cyst or a corpus lium or a luteal cyst if the hemorrhage has undergone fibrinolysis, for example, this is an example of a polycystic ovary with multiple immature follicles and thickened stroma, or whether or not there in fact is some leakage of hemorrhage in a hemorrhagic cyst.

Now this is a very nice example, straightforward of a normal ovary with a mature follicle and several immature follicles.

This on the other hand, is a hemorrhagic cyst.

There's echogenic intraperitoneal fluid on color.

We can see the vascularity to this ovary, so we know it's not tors it, we see significant intraperitoneal fluid.

In fact, when we watch this on cine loop, we can see that the fluid moves around.

It, goes back and forth.

We can see the ovary and in fact, we can see, the fibrillated end of the tube as, we'll see here.

And we know that this is, fluid related to a hemorrhagic cyst.

This being the fibrillated end of the tube.

Post-Menopausal Cysts

In post-menopausal women, it's not uncommon to see a smooth wall cyst, great less than three centimeters, and these are probably inclusion cysts.

Now, in a study which was done many years ago in follow up of patients with greater that or less than five centimeter cysts, you could see that some of these in fact, disappeared in postmenopausal women.

Some of them enlarged and some of them got, bigger.

In a larger study from Scandinavia, you could see that whether or not the cysts regressed is related to age with the younger patient having the more likelihood that, cyst would regress.

Variations of Cystic Masses

Now, the variation of cystic masses that we need to be concerned about are shown here once with septations or papillary expressives.

These are typically epithelial tumors, dermoids, and we need to keep in the back of our mind that there's a variety of, masses that have echogenic fluid in them, and that's dermoids endometrioma.

Sometimes in mucinous tumors and in patients with hemorrhage, the findings of malignancy are shown here.

Papillary expressives only, 50%, however, will be truly malignant.

Some of these are borderline tumor, but thickened in irregular walls and clustered vessels on color are certainly, finding suggestive of malignancy as well as societies.

Now, this diagram shows very nicely what papillary expressives look like.

These are clusters of cells that grow into the, center of the lesion, and out in fact can grow on the outside of the lesion.

In these areas, there's abnormal proliferation of cells.

Now, typically ocular cysts are almost always benign.

However, ones with papillary projections, at least half of these will in fact be malignant.

And here's some examples of small papillary projections in this lesion.

There's a small papillary projection along this wall, which has no increased vascularity associated with it.

This, on the other hand, is a more complex lesion with large papillary expressives and very abnormal vessels in this, ovarian cancer.

And as you can see here, some of the vessels have very low impedance flow.

This is another example of papillary cancer.

And you can see on this, group of images, the papillary projections on 3D.

We can see in this lesion some of the papillary projections beautifully.

And here is a vessel going to this papillary projection.

And as you can see, the blood flow in the, in the, papillary projection has very low impedance.

Complex Lesions

Complex lesions are, a group that can mimic each other, hemorrhagic cysts, endometriomas, dermoids tube, ovarian abscesses, and, dermoids, can have echogenic areas due to sebum.

They can have teeth, calcification and of course hair follicles.

Now the more solid these are, the more likelihood that they indeed are malignant as shown on the bottom of this image.

This is a malignant, teratoma.

Endometriomas are typically these so-called powder burn lesions that occur on the surface of the ovary, or, as shown here, or the uterus or bowel.

The most common place for them to implant is in the uterosacral ligament.

When they grow you, they can become so-called chocolate cyst.

Now, a tub ovarian abscess typically evolves from a corpus lium that has become infected.

And as you can see here, multiple adhesions can form In this patient.

We have, a echogenic mass shown here, a cystic mass, and a lesion with some thin fibrin strands.

So this patient has a large dermoid, a smooth walled cyst, and a hemorrhagic lesion.

And when we do color, we can see that these lesions, these interfaces in fact have little or no, vascularity.

Here we have a lesion that has, no internal vascularity.

And, we can see that, this is a uniformly echogenic lesion.

Endometriomas may have the so-called ground glass appearance.

As we can see in this image of, clotted blood Tube Ovarian complex, the tube has endo andal foles, as we can see here, as little, projections into what is a distended, tube.

Endometriomas can have echogenic foci as, as one can see here.

And, these are, areas of hemosiderin and cholesterol deposits due to breakdown products.

And here is the doppler of that, lesion.

Sometimes there can be some increased flow around it due to fibrosis.

This is a hemorrhagic lesion that has undergone torsion, and there in fact is no blood flow, to this torsed ovary.

This is an appearance of a dermoid cyst with an echogenic area related to sebum and some, vascularity surrounding it.

And here is the, blood flow.

This is a, ruptured cyst with a surrounding solid hematoma.

This is kind of, homogeneous and this pattern, of course is non-specific, but is typical of a resolving hematoma.

This is a lesion that has multiple LOEs within it, and as you can see, areas of increased blood flow in the center of the lesion.

And on 3D color doppler, you can actually see the vessels and their surrounding, normal tissue and the small LOEs of pus.

And we'll see this on the, 3D video, which I'll show you, later in this talk showing the increased vascularity inside this tube.

Ovarian abscess, solid lesions are typically fibroids or metastatic lesions to the ovary or in some cases teratomas.

This is a picture of a, adenocarcinoma of the ovary that's a solid, lesion.

This is a color doppler showing an area that is solid arising from the left ovary in this patient with colon cancer, which was a metastatic tumor with very low impedance blood flow.

And this is the right ovary in the same patient with bilateral ovarian uh, metastases.

This is a patient that has a solid lesion with some cystic spaces, and this is a germ cell tumor.

Most ovarian cancers are of epithelial origin.

Only a few percent are related to germ cells, and this is an example of this very complex solid tumor with low impedance type flow.

Now, one can quantitate the vascular index, and as you can see from these graphs, our experience is that, malignancies have greater vascularity.

But there is some statistical overlap.

Sonographic Differential Diagnosis

So the sonographic differential diagnosis, depends on its location consistency and vascularity, and you really need to know the clinical setting to give the best differential diagnosis.

You can improve your specificity by using color doppler and I will show you some examples of that.

This is the result of a large study in Europe where they came up with so-called rules for diagnosing ovarian cancer.

Basically cysts that are ocular with little or no solid components, and no blood flow are, typically benign, whereas malignancies were irregular had ascites papillary expressions and irregular multilocular, lesions with high color content.

And with this differential, they could have a 90 plus percent sensitivity.

And specificity 3D color doppler or 3D in general is very, very helpful in gynecology.

It allows us to see, better the pelvic mass as well as uterine disorders.

And the vascularity, as you can see, some probes are simple mechanical sectors that scan through an area of interest and build up a 3D image from multiplanar reconstruction.

And this is an example of multiplanar reconstruction of this cystic lesion.

As you can see here in the long axis in the orthogonal plane and in the coronal axis and in the sample volume, that this is a simple cyst with thin walls.

This is a lesion that has very thin, fibrin strands as we can see, as a, a sign of, benignity.

This lesion on the other hand, has more solid and irregular areas, but had no blood flow in the center of this and is typical of a hemorrhagic cyst.

This is a very nice image of a 3D, depiction of papillary expressives within an ovarian cancer.

Now there is a, new probe that is a so-called live 3D or matrix array probe.

It consists of multiple elements and allows a live 3D I'll show you an example, of a pelvic mass.

This is just the typical image, of the liver with a matrix array probe.

You can see, the scan plane is selectable.

The sample volume is continually updated so that, one can, image in any particular plane.

Here we're going, down in, into different levels in the liver.

This is a image sent to me by Dr. We Chen from P King.

And this is a ovarian, mucinous tumor.

And as you can see here in 3D, we've color coded the sepia or yellow or orange is closer, the blue is further away.

And we can see beautifully the internal septations in this ovarian tumor, using this four D technology.

Applications of 3D Color Doppler

Now I'd like to show you how 3D color doppler can be applied.

It allows us better determination of location, organ of origin, allows us to serially evaluate fibroids, uterine malformations and tubal disorders.

And this can be obtained by using a free hand, which is not used that much anymore.

But with automated scanning, the volume that is rendered, can be evaluated by looking in different scan planes.

And this is an example of an ovarian cancer in this plane.

We can see the tumor here in this combined gray scale and 3D color doppler.

We can see abnormal vessels in the area of the tumor.

We can see in this plane the internal vessels that are shown, very nicely on this image.

I'm going to show a, videotape of some of the, cases that we've seen with 3D color.

This is a endometrioma with kind of diffuse echogenic content.

What we're doing first is scanning throughout the plane and seeing, areas of vascularity here on this 3D volume.

We're seeing that there are only a few vessels in the periphery of this lesion.

None of them in fact are coursing toward the center of the lesion.

So this is an example of a benign, lesion.

This is in the other scan plane, and I'll show you the next case which shows, abnormal vessels coursing toward the center of the lesion.

This is another 3D color doppler done transabdominally with a freehand technique.

We're imaging through the ovary here.

We're finding an echogenic papillary area, and, we can see that there's a small vessel going to it.

When we post-process this, image, we can see that, there's a large vessel going to the area of abnormality, right here, which, supplies the ovarian cancer.

3D is very helpful in evaluating tubal disorders.

As I mentioned, this is a, 3D image Moving in allcan planes showing that this tubular structure seen in the long axis, short axis in the coronal plane is, arising from the corneal area of the uterus.

And the 3D scan plane, again confirms that this indeed is a hydro cell pinks as opposed to an cystic ovarian lesion, using 3D.

This is a intramural fibroid with peripheral vascularity.

This is prior to embolization and one can, see that it's supposed to an adenomyosis where the vessels are diffuse.

This, lesion has a peripheral vascularity.

I'll show you some of the, vessels supplying this fibroid.

We're going to select, some of these scan planes to show,

This shows the significant amount of vascularity all surrounding this fibroid.

This is the combined sample volume showing the large peripheral vessel supplying this fibroid.

We can take this sample volume, we can move it in any particular scan orientation.

We can slice and dice it and we can evaluate its overall vascularity, very nicely using this 3D uh, technique.

Here. We're just showing the sample volume and the vascularity surrounding this fibroid.

We can remove the gray scale and look at the vascular tree, and we can follow many patients that have had uterine fibroid embolization, and may have complications after that for the overall vascularity.

And here we'll take off the gray scale and show you the vascular network surrounding this fibroid.

Then we can put back the color doppler.

This is a example of an endometrial polyp and the vascularity in the endometrial polyp that was a malignant polyp, and I hope you can appreciate the vessels being very abnormal.

There's areas of dilatation and narrowing and there's abnormal branching inside of this polyp, and we can appreciate this because we can have a display in 3D um, of this vascularity inside of this polyp.

This is a patient that had, a lesion in the ovary, and the 3D was very helpful in showing the central location of the vessels as opposed to a benign lesion.

Here we have, again, a mostly solid lesion with some cystic spaces and all of the vessels here are shown to be abnormal.

Supplying the center of the tumor here, the multiplanar images that were obtained.

And again, we can see that the vessels course toward the center of the lesion right here.

This is in the coronal plane showing the location of these abnormal vessels.

This is the sample volume where we can see the relationship of the vessels through the morphologic abnormality.

These are all abnormal vessels in the area of thickening inside of this lesion.

And this is the vascular cast image of these abnormal vessels.

This is the leashing that I showed on the earlier portion of the talk.

This is a large tube ovarian abscess.

And here are the abnormal vessels, and we can see the 3D volume here.

I was asked to aspirate this lesion, but I wanted to show them the vessels that may be traversed.

And this 3D was very helpful to convince them not to, pursue aspiration of these lesions.

And here we cut the top of the lesion bloodlessly.

I must add that.

Then we take the Volume and tip it and we can look into the lesion and we can see that, yes, I could aspirate a little, a few of these small LOEs, but the needle would be traversing all the vessels inside of this tube over an abscess, and that would not be a great idea, to perform it.

So, it's very helpful in identifying the proper route for placement of needles and aspiration.

Here we're putting back the tissue that we removed.

This is a 3D image.

As I mentioned briefly, we can use fluid in the lumen and we can identify beautifully the polyp and its vascularity.

As we can see here, the vessels inside of this polyp are seen, and are better seen with 3D representation That,

So the polyp and its vascularity are seen very nicely with this technique.

3D allows us to see the vessel arrangement that the density may correlate to histology.

And finally, I wanna show you some examples of contrast to depict, perfusion.

We can also with 3D technique, determine vessel density and morphology because as I said, tumors have micro aneurysms, stenosis and blind ending pouches.

And we can look at vessel branching patterns.

Now these parameters have been quantitated using the vascularization index, the flow index, which takes into account the amplitude and a combination of the vascular flow index here is a very vascular tumor.

As you can see here, this is another very vascular tumor with some internal vessels.

And this cine loop also shows a relatively hypovascular cyst adenoma with 3D sonography.

We can identify these branching patterns and determine the relative vascular density.

There's been one study which has shown that this data helps reduce the false positive rate in diagnosing uh, malignancies.

Contrast-Enhanced Ultrasound

Finally, I wanna just briefly mention the use of contrast with tumors.

One really needs to look at the capillary blood flow.

Tumors have areas of increased interstitial pressure due to necrosis.

This is a beautiful scanning electron micrograph of, the difference between the vascularity of normal with a art artery going to an arterial, going to a capillary, going to a venial, versus on the opposite side, a very tangled vessel, with very abnormal branching patterns.

So what the microbubbles do is that they course in the circulation, they're about a third, the size of a red blood cell, and they allow us to see vessels as small as capillaries.

We use pulse inversion, techniques.

And here's an example of a lesion that is about two centimeters with a slightly thickened area.

The contrast is injected intravenously and the image that is, built up as shown here, this is the microvascular, which is the persistence image.

And one could see that there was no increased vascularity in the wall of this morphologically suspect, benign lesion.

And we can quantitate the blood flow that we see with contrast using, the following parameters.

We can look at the time to peak the peak intensity and the washout phase and basically the area under the curve.

And when we do that, we can see that this benign lesion has a very quick uptake, a relatively small peak, and a quick washout phase.

Contrast that this is the 3D of this para ovarian cyst with, some vessels.

And contrast that with this, cancer that I'll show you now, This is, I'm sorry, this is a benign lesion.

This is a solid lesion that was suspect for cancer.

But as you can see here with the contrast, we see very little if any blood flow in the center of this lesion.

This was a fibroma.

We'll see that the ovarian cancers in fact have significant enhancement, but this lesion, although it was suspect for cancer, had very little or no vascularity.

And here's the time activity curve.

You see a very quick uptake and a very quick washout phase.

Now watch the contrast in this ovarian cancer.

This is a two centimeter ovary with a one centimeter cystic area.

Watch the microbubbles as they come in and fill.

There's a very large enhancement and we can see from the time activity curve a very high peak intensity and a very long washout phase.

This is in the other ovary, and again, watch the marked enhancement of this lesion.

This was also an ovarian cancer.

And you can also see from this time activity curve that there's a very long washout phase.

Now, when we compare benign from malignant, we can see that there's no change in the wash in phase, but on the maximum enhanced or the peak, there's a significant difference On the washout phase, there's also a very significant difference.

And finally, the area under the curve is significantly different.

Conclusion

So what I've tried to do in this talk is give an overview of the use of various sonographic techniques in evaluating patients with pelvic masses, emphasizing the use of transabdominal to look at the global depiction.

Transvaginal to get the details, color doppler to look at the vascularity and 3D to look at morphology and volumetric changes.

And finally, the, potential use of contrast for evaluating, tumor enhancement and response.

Thank you.