Pitfalls in Transvaginal Sonography - SD

Introduction to Avoiding Pitfalls in Transvaginal Sonography

I am Dr. Oksana Al Taric from the Jefferson Ultrasound Research and Education Institute at Thomas Jefferson University Hospital in Philadelphia.

This talk is about how to avoid pitfalls in transvaginal sonography.

We will go through a stepwise fashion through the transvaginal exam and pinpoint where pitfalls may occur.

The objectives of this talk are first of all to improve the technique of transvaginal pelvic scanning so that we can optimize our accuracy of interpretation.

We are going to re-examine the steps during the transvaginal scanning procedure, and pinpoint where errors in interpretation may occur, and correlate the different positions of the uterus in the pelvis with the transvaginal sonographic images for a better understanding.

Stepwise Approach to the Transvaginal Scan

Basically, think about how you do a transvaginal scan.

You start from the beginning with the history.

To avoid the pitfalls, you want to know the correct O-B-G-Y-N history.

You do want to start with the transabdominal pre-scan.

Then once you are doing the transvaginal, you want to understand your image projection.

Make sure that you have the correct beam orientation.

Check your different points of technique.

Then as you scan, start with the bladder, the cervix, the uterus itself.

Know the blind spots in the pelvis.

Be persistent about finding ovaries.

Maneuver the probe in different ways.

Use doppler at the end and think of things beyond gynecologic conditions.

All of these in a stepwise fashion.

We will discuss here in this talk.

Importance of O-B-G-Y-N History

First of all, know the O-B-G-Y-N history.

It is very important especially in gynecologic and obstetrical history.

To know the age of the patient, to know the parity of the patient, the date of the last menstrual period, the hormonal status of the patient is the patient on any specific kind of hormones for fertility treatment, for replacement therapy, for has had chemotherapy, any type of agents that could affect the appearance of the reproductive organs, any special circumstances in this patient and listen to the patient.

Ultrasound is one of these areas where we actually do still have patient contact.

And while we are scanning, we can hear more detail about the patient's condition, and look for the abnormality actively.

As far as knowing history, when we have a situation of pregnancy, it is very important to know, have there been any pregnancy assisted techniques, because this puts us on a special alert because of the possibility of heterotopic pregnancies in patients who have undergone ovulation induction.

The risk of heterotopic pregnancy is about 4%, and 1% of pregnancies with IVF and GIF procedures end up to be heterotopic.

So we do not just look at the intrauterine pregnancy, we look outside in the adnexal regions.

In this case, there was ovulation induction.

We see an enlarged ovary with cysts, but because of the risk of heterotopic, we look carefully and we spot that not only was there an intrauterine pregnancy here with an embryo, but there was an extrauterine gestational sac, an ectopic pregnancy, and the rest of the ovary was out here.

That would alert us.

We have to know this information now as we are scanning the patient.

We listen and in this situation here, the patient is telling us that the pain is not really in her pelvis.

It seems that the pain is in her abdominal wall.

She came as a pelvic ultrasound, but we convert, we change our transducer to a high frequency linear probe, and we scan the area of pain, which was in the abdominal wall.

And here we see a mass that ends up to be abdominal wall endometriosis.

Another patient who had pain, not really in her pelvis, but in the abdominal wall.

And on talking to the patient, she had had a sarcoma earlier in her life.

Doing a biopsy on this solid mass in the abdominal wall, it turned out that this was metastatic sarcoma years later in a patient who had abdominal wall pain, not specifically pelvic pain.

Transabdominal Pre-Scan

Another way to avoid problems, pitfalls, is to pre-scan transabdominally.

Transabdominal pelvic sonography in its pure form is no longer really practiced.

What we are talking about here is still to take a look at the pelvis transabdominally, but not necessarily to have a full bladder.

A full bladder is not necessary anymore.

So we can have a patient come in, in a natural state, bladder could be empty, bladder could be partially filled, put her on the table, take a quick look around the pelvis, looking for a large mass, a large uterus, something that could easily be missed by just doing transvaginal sonography.

So when we schedule these patients, they just come in, in a natural state.

We look at them quickly, fuse spot, fuse, transabdominally, have them empty the rest of their bladder.

In the meantime, quickly set up the transvaginal probe and do the examination.

We do have some evidence from an article out of Boston in a study that they did on 206 patients transvaginally.

When they did transvaginal alone, that was sufficient to visualize all of the significant findings in about 85% of patients.

That meant that an additional 15% of patients still required a transabdominal scan without a full bladder to get the information.

Only 1% of them actually required filling of their bladder.

So if a patient comes with an empty bladder and happens to be in this very low percentage that she would need a full bladder, we will then have her drink and fill her bladder.

This may happen, for example, in a very young girl, a virginal patient, a very old patient who cannot tolerate a transvaginal exam, but that will only be a very small percentage of patients that have to sit and wait and fill their bladders.

The value of doing this transabdominal pre scan is that it gives us a general pelvic overview.

We can quickly estimate the uterine size and see, will we have trouble imaging this uterus with the transvaginal probe or not.

We can look for a mass above the fundus of the uterus, such as a pedunculated myoma or a large ovarian mass, or even in an ectopic pregnancy in a high position.

And we can quickly assess for intraabdominal fluid with the same probe.

If you do transvaginal sonography only and bypass this step, you are liable to miss urban, interpret a large mass in completely, scan a large uterus, miss an intrauterine pregnancy or an ectopic pregnancy, or a mass in a high location.

Misinterpret an ectopic as an intrauterine pregnancy.

That is something that is unusual but could possibly be done or miss a large hemoperitoneum by not checking the right upper quadrant.

If you scan only transvaginally, as in this case here, you could miss a large mass.

Now, this looks like a perfectly normal uterus.

However, the transabdominal precan showed us that there was a large mass somewhere up high above that uterus.

Even here on an extended field of use scan, we see that it is a very large mass.

It is actually a pedunculated myoma attached to the fundus of the uterus.

If you just started with the transvaginal, how would you know that there was something attached to the fundus of the uterus?

So we go systematically from transabdominal to transvaginal.

Now, here is another one.

If you just did, transvaginal, this looks like a somewhat small uterus.

There seems to be an endometrial lining here, but this was actually a very long uterus on the pre-scan.

And when we, we knew that, so we were questioning this, where is the, this, this only measured about four centimeters.

Where is the rest of that uterus?

So we knew that it was about 11 centimeters long.

We searched more carefully, opened up the depth, found that it was really retroflexed, and found the entire uterus.

What we were actually looking at was only the cervical part, and we were not imaging the corpus at all.

Here is another example.

Here is a transabdominal pre-scan that showed us a very high location of an ectopic pregnancy.

And so therefore, when we looked transvaginally, we were very careful.

If we would not have seen it, we would go back transabdominally and study it in more detail.

Here is a situation where an ectopic pregnancy was mistaken for an intrauterine pregnancy.

Now, first of all, there was a live embryo here, okay?

And on the transabdominal pre-scan, one sees that something is not right with the lower uterine segment, we do not have the normal appearance of a cervix blending into the uterine walls.

We have some kind of a thickening.

Is there a mass down here?

It does not look normal, so we have to be careful.

Now when we scan to figure this out, and what had happened here was the uterus was pushed way to the side, and the ectopic pregnancy was actually sitting in the middle of the pelvis, so that it, it almost looked like an intrauterine pregnancy.

But because we knew that something was not right, we were able to find the uterus and make that call.

We do not want to miss a large hemoperitoneum.

When you have this pre-scan, you just take the same probe and slide it up under the ribs.

This was a patient with a ruptured ectopic and had a very large amount of a hemoperitoneum in the right upper quadrant.

We do not change the patient's position.

We do not change the probe.

We just slide it up under the ribs.

If you do transvaginal alone, what you have to do then is change transducers, convert, have the patient move back up on the table.

This could shift the fluid back down into the pelvis.

Does not make that exam as reliable.

Image Projection and Beam Orientation

Now we have to also now understand the image projection.

The transvaginal image is projected 90 degrees counterclockwise on the monitor from what we think that we are seeing anatomically.

So let us look at this. Here is of the uterus.

Here is the probe with the beam sagittal.

This is how it is in the body, but the machine rotates it 90 degrees counterclockwise on the image so that the image is at the top of your picture and comes out.

So this is anterior here.

This is the anterior part of the uterus.

And when it is rotated, this is anterior.

So this is anterior posterior, this is cranial, and this is coddle.

Let us do that again. See, coddle is this way.

Sway, coddle right here.

This is cranial anterior, posterior.

The same thing happens when it goes coronal or cross-section.

It still rotates 90 degrees, but in this case, the right side stays on the right and the left side stays on the left, so that when the beam goes into the body, yes, the machine does invert it or rotate it 90 degrees, but it is easier for us to understand the right and the left side.

Why is that important? Well, that periodically helps us figure some things out.

As in this view here, we have the uterus, and it has an interface here in the middle of the cavity.

Now, we know that this is anterior and this is posterior.

So that means that this fluid level is in a dependent position, and the fact that it is up and down on the picture does not bother us now, cause we know that it something is layering within the uterus because this is anterior, this is posterior, and here is an ed nal mass, a sagittal image of an adnexal mass.

We know this is anterior, we know this is posterior.

Our, our level shows us that dependent material is to the posterior.

And even though the levels up and down, we still know that is dependent.

That happens, that helps solve this complex cases like this one where the echogenic material is on the non-dependent portion, which means it is floating.

So now, once we make that decision, we know this is anterior, this is posterior, this is floating fat floats.

We now have a 99% diagnosis of a dermoid

Check beam orientation.

We have to be careful which part of the beam is up and which part is down.

And that is sometimes hard to do on this transvaginal probe, which has a very small rounded interface, and it is hard to figure out exactly where the beam is.

This could be, you could, you could have rotated the probe, someone could have changed, left right on the machine.

Press the wrong button.

So the way we do it is by checking where is the urinary bladder?

So why do we even bother with this?

Well, first of all, we have to make sure that the image is not reversed.

That would help us with the proper uterine position.

So if it is an antivert uterus, if it was reversed, it would look retroverted and vice versa.

Also, when we turn 90 degrees into the transactional plane, we want to make sure that the right side is correctly registered on the, so we do not mix up the placement of a mass.

And it gives us a brief interval of time to just focus a little bit on the bladder.

And sometimes we pick up bladder abnormalities.

So this is where it becomes important.

You have a picture like this, and it looks like the uterus is anti verted, but you see, we could actually just press the left right button and flip it around.

So how do we really know what is the true position of this uterus?

Is it a anti verted or a retroverted uterus?

Well, the only way to really tell is to check the position of the bladder.

On a sagittal scan, transvaginal scan of a uterus, the urinary bladder should be in the left upper corner of the uterus of the image.

If the bladder is on the right upper corner, then you are reversed.

So here the bladder is on the left upper corner.

This is an anti verted position.

Now, when you rotate the probe counter clockwise, we usually start, of course, in the sagittal projection.

You always keep your thumb on the notch.

There is every transducer is notched in some way.

Either has a flat surface or a line, or a notch or something that shows you that that is how the beam comes out sagittal like this.

So now you must rotate it counterclockwise.

Do not rotate it the other way clockwise, or you will reverse your right and left sides.

Okay, so we have taken the sagittal beam counterclockwise.

Now we can scan the pelvis and correctly put place the right and left side.

Technique Checks: Depth, Gain, and Focus

We do have to check our technique.

We want to check our depths.

Always check your gain, which means your TGC and your overall gain, and make sure that the focus is set correctly.

First of all, adjust your depth settings.

You should start with the maximal depth setting.

You want to see as deep into the pelvis as possible.

You want to look around and then reset your depth so that you can see two to three centimeters beyond the margin of an organ.

When you start out, you should have your depth open, quickly look around, and then reset it.

Fill up the picture with your organ of interest, in this case, the uterus, but do not fill it up too much.

Do not let the back wall of the uterus come up to the very edge of your image, of your picture, because a mass that is exophytic or very close adjacent to the uterus could be cut off.

In this case, this was too much of a change in in depth.

This was a very shallow depth and something back here behind the uterus could have been cut off, so this would not be good.

We want to step back, make sure we can clear two to three centimeters beyond the organ.

Here was a situation where the depth, here we are focusing on the cervix.

The cervix was now made to fill most of the picture.

And what is happening here is we are missing the fact that there is a very large mass here behind the cervix.

If we had our depth maximal, we would have seen that this, there was a mass be deep in the cul-de-sac.

And of course, if we had our transabdominal precan, we would know that something is going on and there is a uterus and there is a mass, and we would have to evaluate everything.

So this was going backwards.

But if you were going in the proper sequence, transabdominal, then you go to maximal depth, then you change to shallow depth and high detail, you would have covered all bases.

Another example, this looks like almost a uterus with some fluid inside of it.

But actually this is just the cervix with a little bit of fluid.

The entire corpus is missing here because our depth is too shallow.

We want to open our depth, look around, then change our depth and focus on parts of the structure.

Another example, an ovary with a physiologic cyst in it.

If we would have had maximal depth first, we could have used that cyst to scan deeper into the pelvis and see that there is an ectopic pregnancy back here.

So we have to start with maximal depth, then focus closer on our on an area of interest we should scan so that we should image that so that there is a two to three centimeter margin beyond the border of any mass so that we do not miss exophytic or adjacent masses.

Here is a uterus that just about makes it into our field of view, but the whole anterior part here, al aspect, are not well imaged.

It just so happens that there actually is a mass sticking off the fundus of the uterus.

And this was a pedunculated myoma that was pressing onto the bladder and then causing dysuria in this patient could have been missed.

Now gain, we have to adjust overall gain and of course our TGC curve.

And we also want to avoid false echoes within any kind of a fluid structure so that if we see free fluid or fluid in an area and it has some echoes, how do we know that those echoes are true?

Or actually false echos.

Here is for example, a patient with a collapsed urinary bladder.

We are scanning transvaginally and there is some free fluid in the pelvis.

There is some bowel loops, but we see some echos.

Are those real?

Is this a hemoperitoneum or is this puss in the pelvis?

Or is it just our gain setting?

Well, we compare with a known anti coic area.

The bladder has clean urine and this has echoes.

Therefore, these are real. And this was hemoperitoneum.

Whenever we have a fluid structure, we should do a gain analysis, a low gain, high gain analysis.

There was a pelvic mass here, it looked like it was completely anti coic, looked like clear, like the bladder.

But when we slowly crank up the gain, we see that this mass fills in before the urinary bladder.

So we know that these echoes are real and we have to explain them.

This was a chronic fluid structure that had developed some crystalline material.

Scanning the Bladder

Okay, so we have our technique correct.

We know our orientation.

Now we start scanning, and the, before we, we go looking around in the for uterus and ovaries, we should take a quick peek at the urinary bladder.

So to do this, we have to angle the probe anteriorly, and that sometimes gives us that opportunity to find a very anterior mass.

Like in this patient. This was the uterus here, and we were trying to find the bladder, and we found that instead there was a very large mass there.

Here is another patient we tried to angle for the bladder, and there was an endometrioma plastered to the anterior surface of this uterus.

So we can recognize anterior masses much better, not miss them.

The other thing is we can find urinary bladder masses or find some other condition in this patient who was in severe pain.

Young woman in severe pain, it looked like she had a dilated bladder with the transvaginal probe.

As we scanned around, we tried to make sure that we saw the bladder and we found the little corner.

It is in the left upper corner of our picture.

And this mass, which happened to be the same mass, we realized that this was a mass, an ovarian mass that had found its way anterior to the uterus and was not the bladder at all.

The bladder was actually small and collapsed, and only because we looked for it were we able to see that there was truly a large mass in this patient.

And it happened to be a torsion.

We do not, so we do not want to mistake a cystic mass for the bladder.

This was an adnexal torsion.

There was the infarcted ovary, there was the dilated tube, and it is separate from the collapsed bladder.

Now, when we take a peek at that urinary bladder, which we often just ignore during our scan, we may find something that is very significant.

This was a 30-year-old patient.

She was having her first trimester ultrasound, and we just took a little peek and we saw an irregularity in the bladder.

Took a little closer view.

This was her pregnant uterus, took a closer view and found a mass converted to a full bladder view, and found an irregularly shaped mass.

This was a transitional cell carcinoma in a first trimester patient.

This was a 80-year-old lady, she is postmenopausal, and she came for postmenopausal bleeding evaluation.

But after we evaluated her uterus and her ovaries, we found that everything was fine.

The endometrium was nice and thin, and we spotted in her bladder a couple irregular masses.

Further investigation revealed that these were solid masses, and this woman had two transitional cell cancers in her bladder.

It was, it actually happened that this was not postmenopausal bleeding.

This was actually hematuria.

She complained that she wiped herself with some tissue.

She saw blood, and she right away thought it was vaginal spotting, but in fact, this was urine that had blood hematuria.

Scanning the Cervix

So now that we have quickly analyzed the position of the bladder and the appearance of the bladder, we now move to the cervix.

You should look at the cervix separately and directly.

You want to be perpendicular to the uterus.

You want to leave the rest of the endometrium and the fundus and the corpus out of your picture, 90 degrees to your area of interest.

This helps you to quickly see is there any kind of mass inside the cervix.

In cases of ectopics, a cervical ectopic could be there.

Deep cul-de-sac is imaged.

That could be a place where a mass is hiding.

This endo cervical line is your guide into the endometrial cavity.

This helps you with uterine positions.

So we want a nice view of the cervix.

This is not adequate.

Such a view of the cervix where the cervix is half cut off.

Here is not adequate. We want to be 90 degrees.

Here we are a little better, but not good enough.

We go completely 90 degrees, and we see that there is a mass in the cervix.

It is actually bulging out.

The mass was here, and we were only imaging a part of it.

It because we were, we were not seeing the complete fundus, and we were not seeing the complete cervix.

So we should start with the trans vaginal view of the cervix.

And in this case, doppler showed that there was a large vascular pedicle to this, and this alerted the surgeon that there could be hemorrhage during removal of this mass.

Here is another case where a pitfall did occur.

A patient came in, overnight bleeding, and a quick scan showed that it was an intrauterine pregnancy, and everybody was happy that there was an intrauterine pregnancy.

However, the patient continued to bleed and bled profusely, which resulted in emergently going to the OR and sustaining a hysterectomy.

What had happened in retrospect was there was a cervical ectopic, well, the cervix was never looked at.

The fact that we saw the intrauterine pregnancy was made everybody feel that this was just an IUP and nobody really took the time to investigate the cervix, which had another pregnancy in it, a much more dangerous pregnancy, which resulted in massive hemorrhage to this patient.

This was in the days before ir, the days before we were using methotrexate.

But this poor patient lost her uterus because nobody spotted that there was an abnormal pregnancy in the cervix as well.

It gives us a quick look at the deep cul-de-sac where we could see echogenic fluid.

In this case, hemoperitoneum, we could see even peritoneal implants in these patients who have histories of malignancies.

The cervix is a guide to the rest of the endometrial cavity.

Here we, when we follow the endo cervical line, it leads us straight into the cavity.

And we know this is an intrauterine pregnancy.

We would never mistake this for being anywhere else here.

We, it guides us straight in.

We get the orientation, we can measure the endometrium, which is a proper measurement.

Here was a patient, a post-menopausal woman with bleeding.

She has a small uterus, and we saw that there was some echogenic material in here.

We wanted a good measurement of her endometrial thickness.

So we use this cervix as a guide to lead us straight in.

We have a longitudinal position of orientation.

We know this is the longitudinal uterus, and now we can measure the endometrium correctly, which was way too thick.

And this was endometrial carcinoma.

Uterine Positions and Their Impact

The position of the it helps us with position of the uterus.

The uterus can have variable positions in the pelvis.

And this can become problematic when we are scanning.

So we use this cervix to guide us into the endometrial cavity, and then we can establish whether there is some degree of obliquity in the to the uterus, is, we can see is it tilted, is it rotated?

So let us look a little closer at how our beam works with this kind of uterus.

This is the standard, standard sagittal scan through the uterus.

Now, if we have a tilting a a a a tilting to one side or the other, we keep our beam in a longitudinal plane down the middle.

We, we would have followed it through the cervix into the endometrial cavity.

And we realize that the longest length of this, the longest axis, is tilted from midline.

It is, it can also be oblique and rotated.

Sometimes the uterus is oblique.

So to get its longest axis, we have to actually rotate the beam.

Now notice where I have this black dot.

This black dot means that it is the top of the ultrasound beam.

Okay? So as we come in sagittal, this is the top of the beam.

And in order to find this uterus, which was actually rotated and oblique, we had to turn so that the top of the beam is here.

And in order to then get, that is its longitudinal axis, but to get its coronal axis, we have to keep rotating the probe counterclockwise 90 degrees, which ends up way down there in order to get our coronal view of the uterus.

It would be very hard to understand this if you did not think of how your beam is positioned, how the cervix helps you and leads you into the center portion of the uterus.

So here is an example.

This uterus was rotated and obliqued and tilted, and the person scanning had no idea what was going on, and just took some kind of endometrial measurement.

Well, what had happened was, had you followed the protocol, get your longest axis of the uterus, then rotate 90 degrees, one could measure the endometrium correctly.

Endometrium should have been measured on a 90 degree plane from this.

The uterus can be anti verted.

Usually it could be in the mid portion of the pelvis or it could be retroverted.

And we have to understand the position so we can place masses correctly, place fibroids correctly in such a plane.

So here is the standard view. This is sagittal.

This is anterior.

So this is the anterior wall rotated 90 degrees.

Let us look at that again. This is the anterior wall of the body, but this is the anterior wall of the patient patient's uterus.

This is the posterior wall of the uterus.

We know that the fundus is pointing towards the anterior of the patient's body, but the anterior anatomic wall is here.

Notice that the anterior wall closest to the beam, closest to the beam is on the upside of the picture, Right?

The beam hits the anterior wall.

First anterior wall is closest to the origin of the beam.

The uterus has somewhat of a donut shape, has an endometrium located centrally.

Now look at this uterus.

It is a mid position uterus here.

It points down, it is parallel to our beam.

And when we turn 90 degrees, we actually get a true coronal frontal cut of the uterus.

So this is a mid position uterus.

Nowhere near does it look like the verted uterus turn 90 degrees, send a coronal beam through the uterus, and you get a coronal shot.

But both of these uterus are parallel to the beam, which means we are not going to get as good resolution.

So here is, here is an, here is the example.

This is the sagittal longitudinal beam.

Notice a lot of dropout.

Notice that there is an IUD, but we can hardly see its position.

It is because this kind of uterus is parallel to the beam.

When we turn 90 degrees, we do not do much better.

We still do not see very well because it is still parallel and we hardly see that IUD that is the mid pelvis uterus.

Now the retroverted uterus, okay, this is the flipped back uterus.

Watch where the walls are.

The anterior wall of the uterus is here.

The anterior wall ends up being deep in the pelvis so that the beam hits posterior wall, anterior wall, anterior wall is in the deep part of the pelvis opposite from the verted uterus.

So this is anterior wall, this is posterior wall.

Let us do that again. Beam strikes posterior wall, anterior wall beam strikes posterior wall, anterior wall.

This is the anatomic anterior wall of the uterus.

So when you see a cross section of a uterus like this, and it has a fibroid on it, you should not jump to conclusions that this is a posterior fibroid, because the answer here to this question, which wall is the fibroid on?

The answer is, well, it depends on the position of the uterus.

If this is a retroverted uterus, then this deep fibroid is on the anterior wall.

If this is an anti verted uterus, then it will be on the posterior wall.

So we have to know the position of the uterus.

So here it is, with the fibroid retroverted uterus has a fibroid on the anterior wall, so that ends up to be deep in the pelvis.

The anterior wall is deep, so the fibroid registers deep in the pelvis.

Okay, let us do that again here.

The beam hits posterior wall, anterior wall.

Anterior wall is the deep part of the pelvis.

Now, obstetricians and gynecologists do not always get hung up on anti verted position, retroverted position, because uterus can actually be flipped back and forth.

Let me show you an example here.

This is a patient with a, a small cation in the anterior wall.

A few seconds later, the uterus flips into a retroverted position here.

And now we can prove to ourselves, yes, that is the anterior wall of the uterus.

And you can sometimes do this with the probe by changing position.

Here, the probe is in the anterior fornix.

Here the probe is in the posterior fornix, and you can sometimes have this uterus flip positions within a matter of minutes.

The important thing is to understand where that anterior posterior wall is so that you can place masses correctly or fibroids, and not confuse the surgeon.

Blind Spots and Finding Ovaries

You should know the blind spots in the pelvis.

The blind spots are far above the fundus of the uterus, far lateral on the pelvic sidewalls, deep in the cul-de-sac or very far anterior.

You should be persistent about finding ovaries.

Here is a fibroid uterus.

You look quickly transabdominally, you see that the uterus is big.

You do not see any other masses.

You look transvaginally and you realize that you cannot see most of the uterus, but you use this opportunity to look for ovaries.

You find an ovary beautifully, but you cannot find the other one.

So you have to go back Transabdominally, go back transabdominally, and look high along the iliac borders to see the ovary.

This is a complete evaluation.

You do not just stop and say, I cannot see anything.

I cannot see ovaries. You make an effort to find them.

Maneuvering the Probe

Maneuver the probe, push with the probe, check mobility of the mass, separate masses, elicit pain, change position of the uterus.

To improve imaging, use your non scanning hand to palpate a mass or pull down on the ovary, pull it down towards the pelvis, create a wave, see if things move, twist and turn the probe to try to unravel tubular masses.

Here is a looks like an ovary, but the patient had a question of an ectopic, and we saw something that possibly could be an ectopic, but could this be a corpus lium in the ovary?

We would push with the probe and we try to separate them.

And it turned out that the ovary rolled that way, and the ectopic moved this way so that they were actually separate structures and not connected.

Here is a mass of, we want to prove is that it is stuck to the uterus or not.

So we push on it.

And when the mass moves, the uterus moves at no time were they moving in separate directions.

We can change position of the uterus by pushing around here.

This uterus looks like it is kind of parallel with the beam, and we know that is not optimal for sonography.

So we go, we push the probe into the posterior fornix and push that uterus a little bit, and now it flips back posteriorly into a retroverted type position, which makes it more perpendicular to the beam, which is good for sonography, good for B scanning, and we get much better detail about the uterus.

Another example, uterus looks kind of clumpy, kind of parallel to the beam.

Cannot resolve even endometrium.

We push the probe into the anterior fornix, and that brings us closer, puts the uterus more in a perpendicular orientation, and we can actually measure the endometrium and see things much better.

Maneuver your probe, twist and turn.

Do not mistake a tubal mass for a septated ovarian mass.

Try to unravel septated masses.

Make sure they are not tubes that are folded over on themselves.

In this case, it looked like there was a cystic at NAL mass, but when we turned the probe around, we saw that the, this was opening up into a dilated fluid-filled tubular structure hydros.

Again, a mass that looks like, like a septated ovarian mass.

But when we move the probe around, twist and turn, we unraveled this mass and we realized that it is a hydrus helpings and not an ovarian mass at all.

Use of Doppler

Another thing to avoid pitfalls is use doppler.

Use it liberally.

It will help you avoid pseudo ovaries.

Helps you find true tubular structures versus vessels.

Helps you work out unusual cystic masses or unusual uterine masses.

Confirm, confirm colored doppler.

Well, you have to confirm colored doppler.

It is a spectral tracing.

That is one way to avoid pitfalls.

And with torsion and ring of fires, I want to make a couple comments.

Here is an something that looks kind of like an ovary.

You turn on your doppler.

It is not, it is just a cross section of the para uterine vessels.

We make up ovaries all the time, so we have to be careful with this.

What is happening here is we are slicing through some of these vessels that are coming in to the uterus.

So we do not want to make that mistake.

Here is another way of avoiding pseudo ovaries.

It looks like ovary filled with follicles, but when you turn on it and work it out, you realize these are just otan cysts.

In the uterine cervix.

Use doppler for tubular structures. This looks like a hydro.

So pinks turn on color. Oops.

It is just a vessel, a vein. This one looks like a hydro.

So pinks, nope.

It is filled with blood flow and that is just a prominent vessel.

How about this one where there is a postmenopausal lady that has a quote cystic mass, but there is something not quite right about this cystic mass.

Where is the through transmission?

Well, it is certainly as anti coic as the bladder, but we do not have good through transmission.

When something does not look right, turn on the doppler.

And this happens to be an iliac artery aneurysm.

Not exactly a job for a gynecologic surgeon to handle.

Unusual areas in the uterus that are puzzling to us turn on the doppler.

In this case, there was myometrial in homogeneity and had some little irregular cystic areas.

We turn on the doppler and it is high flow with low resistance.

Turns out to be an arterial venous fistula.

Could be an arteriovenous malformation.

It was composed of tortuous tubular cystic structures that had an unusual pattern.

Again, this is not something that would be surgical.

Now, when we do doppler, please keep in mind that any findings with colored doppler have to be confirmed with a spectral tracing.

Because colored doppler ultrasound signals may show artifactual flow.

Here is a mass.

Looks like it has some blood flow in it, but when we do a spectral tracing, we cannot really get a good arterial or venous signal.

Cause these are flash artifacts at the periphery of the mass.

Yes, we do have arterial blood flow, but there was really no true flow inside the mass.

Here is another case where there was a pelvic mass that had it seemed some blood flow.

This is a power doppler.

Well, we do a spectral tracing and we see for sure there is arterial flow.

And this now is a solid mass at nexel mass, which turned out to be a tumor deposit in the pelvis.

Ovarian Torsion and Doppler Pitfalls

Now, ovarian torsion is an area is fraught with pitfalls.

That would require a whole separate topic for a lecture.

But I just want to highlight a point that when we do doppler with ovarian torsion, we should not rely solely on the doppler for the diagnosis of torsion.

Why? Because absent ovarian blood flow does not mean ovarian torsion.

We may see absent flow even in a normal ovary.

This could be because of technical reasons.

This could be because of physiologic reasons that the ovary is resting in that part of the menstrual cycle.

And now the opposite of that is presence of blood flow in an ovary does not exclude torsion.

You can have an ovary that is undergoing torsion, and often we do see arterial or venous blood flow.

And that is actually good because that means that that ovary is probably salvageable.

It does improve our ovarian salvage rate because there is still a blood flow supplying that ovary.

So we should trust the 2D picture more than we trust the Doppler.

As far as ovarian torsion, we can look for 2D signs mainly and enlarged swollen emus ovary.

Many times the follicles are pushed towards the periphery of the ovary.

Sometimes there is an ovarian mass that causes the twist.

So the 2D impression is very important.

Blood flow. Seeing arterial or venous blood flow within a swollen ovary with peripheral follicles is a good thing.

We should not discount the fact that this could be torsion because this is a salvageable or, or hopefully will be a salvageable kind of ovary, which it was in this case, they were able to untwist the ovary and this 23-year-old woman did not lose her ovary.

Ring of Fire Pitfalls

I want to make a couple comments on ring of fire because that is another big pitfall.

Ring of fire was first described with ectopic pregnancy and has sort of stuck in our minds as a sign of ectopic pregnancy.

Well, yes, it could be a sign of ectopic pregnancy, but much more commonly it is a sign of a corpus lium.

A corpus lutetium cyst is much more likely to have a ring of fire, and it is much, much more common than the ectopic pregnancy.

Here they look identical.

Either one could be an ectopic or either one could be a corpus lium.

And that ring of fire statistically is more likely to be related to a corpus lutetium than to an ectopic pregnancy.

So once again, we should not rely on the ring of fire.

We use the 2D, not the Doppler to differentiate the ectopic from a corpus lutetium.

The ectopic is separate from the ovary.

The corpus lutetium is part of the ovary, so that is an important point.

Thinking Beyond Gynecologic Conditions

And last, but not least, when you have gone through all these steps carefully trying to avoid these pitfalls.

And if you are not coming up with an explanation for the patient's gynecologic complaints, think of some things outside of GYN conditions.

Think of urinary tract problems like renal calculi, in which case you would go looking for a renal calculus.

This is a convert here to a transvaginal.

There is an echogenic focus here, which could be a little, we are we are suspecting a ureter vesco junction stone here.

We put on our color.

The twinkle confirms that that is a stone.

And the jet shows us that there is urine flowing past the stone, but it is spraying out into the bladder.

It does not have that nice little jet because this is serving as a partial obstruction.

So we would do the full evaluation.

Here is another example. A stone in the distal ureter.

Beautifully documented by transvaginal sonography.

Turn crosswise. There is the echogenic focus with the acoustic shadow.

And think of not just gu system, think of GI conditions, appendicitis, inflammatory bowel diseases, abscesses, colon, cancer fistula.

You can pick those up. Transvaginally.

Here is appendicitis.

This is a pelvic appendix that caused gynecologic symptoms, and it has we look for that gut signature.

We look for a blind ending tubular structure with layers and appendicular if we are lucky.

Here crosswise, we can see multiple rings, hyper coic, hypo hyper hypo hyper.

These, this is gut signature, turn longitudinally blind ending tubular structure tender painful next to the ovary.

Irritates the ovary presents as pelvic pain, not as right lower quadrant pain.

Another case here where we suspect something else going on because we cannot make a a, a gynecologic diagnosis.

And in this case, a mass.

We look more carefully, we realize there is a calcification.

That is the, and there is a rupture, and there is now an abscess ruptured appendix with an early abscess in the pelvis.

So we think outside of gynecologic conditions.

Review: Avoiding Pitfalls in Transvaginal Sonography

So in review then, how do we avoid pitfalls in transvaginal sonography?

We go systematically. We get a good history.

We scan, pre-scan transabdominally.

We make sure we understand how the beam is coming out of the transducer and how our image is projected onto the screen.

We check our technique.

We check for depth gain, focus.

We will then look at the bladder, the cervix, then check the uterus, look around in the adnexa, know our blind spots, make sure we find the ovaries, maneuver the probe, use our doppler.

And in the end, make sure if we do not have an answer, think beyond gynecologic conditions.

Thank you for your attention.