Pelvic Floor Imaging - HD

Pelvic Floor Imaging

I'm gonna be speaking about pelvic floor imaging.

My disclosure is that I have received support in research from GE Medical Systems.

In discussing the topic of pelvic floor imaging for disorders, I'm gonna be covering the following topics.

They include normal sonographic anatomy of the female pelvis using the trans peroneal approach, sonographic appearance of suburethral slings and mesh, abnormal sonographic conditions which may cause urinary dysfunction, sonographic appearance of postoperative complications after surgery.

And then finally I'll discuss the role of MR versus ultrasound in the imaging of pelvic floor disorders.

Growth and Importance of Pelvic Floor Disorder Imaging

Pelvic floor disorder imaging may be one of the fastest growing areas today.

The reason is because we have an aging female population, about 50% of postmenopausal women have symptoms of pelvic floor disorder.

The lifetime risk in the United States of at least one surgical procedure in a female is about 20%.

As a result of all this, it's been estimated that the imaging of pelvic floor disorders is projected to increase as high as 45% in the next 30 years.

Clinical Factors and Risk Factors

The clinical factors relating to pelvic floor disorders include the ones that I list here on the slide, and the overwhelming factor is that of being a female, over 90% of the patients that you will see will be female.

Unfortunately, that is something that has come about by a combination of factors, including the fact that we of course have problems with having multiparity and some of the other risk factors you see here.

Other risk factors include increasing age increased BMI multiparity, decreased estrogen and menopause and poor collagen.

Pelvic floor disorders, of course are caused by weak pelvic floor muscles and supporting structures.

Clinical Presentations

There are two clinical presentations for pelvic floor disorders and they include stress urinary incontinence and pelvic organ prolapse.

Patients who present with stress urinary incontinence, complain of leakage of urine during things such as exercise, coughing, laughing and straining.

Whereas those patients who have problems with pelvic organ prolapse tend to mainly complain of discomfort, some kind of pressure in the pelvis.

Unfortunately, some of them even feel the organ falling out, for example, of the vagina symptoms that they have associated with this prolapse tend to be referable to whatever organs are involved.

Ultrasound Equipment and Examination Protocol

The ultrasound equipment which can be used for this examination include a curvilinear 3D transducer and in my laboratory we use a relatively low frequency transducer, which is between four and two megahertz.

One can also use, as Dr. Uras noted, a 3D vaginal transducer.

And in some laboratories a combination of both of these transducers is used.

Any examination protocol should include not only documenting the organs at rest, but they should also be documented with the patient performing Kegel and Valsalva maneuvers as noted again by Dr. Protos 3D imaging is really important in this evaluation.

The reason for that is because it's that transverse or oblique coronal image, which is really the key image that we need in order to evaluate the type of surgery which has been done in these patients.

Cine clips are also very useful and this is also because some of the disorders really aren't seen until the patient performs Valsalva or some of the problems get worse with Valsalva.

I really encourage you if you're planning to do this type of examination, to get the kind of equipment you need that has both 3D imaging as well as cine clip documentation.

Normal Sonographic Anatomy of the Female Pelvis

I'm now going to be reviewing the female pelvis, just the normal anatomy.

The image on your left is a schematic of the female pelvis and the image on your right is an ultrasound, transperineal ultrasound in the parasagittal view.

This ultrasound is performed along this yellow dotted line and what you see here is the symphysis anteriorly with shadowing the urethra, which leads to this bladder and then just posterior to the urethra will be the vagina and then posterior to that will be the air-filled rectum.

Again, I want to emphasize a lot of your diagnostic imaging is gonna hang on that 3D image.

One of the key images is the transverse or oblique coronal view, which you see here.

I'm comparing it to the comparable CT scan.

This is the reconstructed ultrasound image showing the symphysis, the urethra, vagina, and rectum.

As I stated earlier, there are two presentations for pelvic floor disorders and it's important to be aware of this.

So when you're talking with the patient, you can anticipate what kind of treatment they have either had or will have.

If a patient comes in with stress urinary incontinence, then most likely if they've had treatment, it's been some type of suburethral sling.

There are two types of suburethral slings that are performed that of a retropubic and transobturator tape sling.

The material used looks just like this in pelvic organ prolapse because the organ involved generally requires a broader area of support.

Now you're talking about material, which is what we call mesh material, which is this here.

The shape of that mesh depends on the organ involved.

This mesh is extremely thin.

If you actually feel it, it feels like one layer of gauze.

Sonographic Appearance of Suburethral Slings and Mesh

At this point, I'd now like to turn to the sonographic appearance of these surgical materials.

First of all, I'm gonna describe the midurethral sling.

Both types of slings look the same on the parasagittal exam.

This is the midline parasagittal exam with a symphysis anteriorly.

The urethra, the vagina has some air, so it's a little bit bright.

The rectum is back here and between the urethra and the vagina, you see there's a short echogenic line and that is a suburethral sling.

As I said, both types of slings look the same on the parasagittal view.

That's why the 3D image is so critical.

Without the 3D image, you don't know what kind of sling you're looking at.

The images on your left are schematics of the pelvis.

This is a retropubic tape sling.

This particular sling is located in a fairly tight U around the bladder.

This is the white line that you see in the schematic and on the transverse or oblique coronal view, what you see here is, again, let me orient you symphysis urethra vagina.

Here you see this sort of U-shaped echogenic material that is a retropubic sling.

This is in contrast to the other type of sling that is a transobturator sling because the arms of the transobturator sling go through the obturator foramen.

The shape of this sling is more horizontal compared to the other sling.

It's that transverse or oblique coronal view, which is gonna give you that information.

Here's the anatomic information.

Here's symphysis, urethra, vagina's back here and between the urethra and vagina.

You see that this echogenic material is relatively horizontal and that is the sign of a transobturator sling.

Both types of slings are very well seen sonographically, they both appear as echogenic lines.

Sonographic Appearance of Mesh

Now let me turn to the mesh.

What does mesh look like with ultrasound?

Mesh, as I stated before, can be variable.

It depends on what organ is being supported.

In the old days, like about 10 to 15 years ago, surgeons would just take this material and sort of cut it out themselves, sort of estimate what they need, cut it out, and then put it in the pelvis.

However, more recently we now have pre-cut kits, so surgeons can just fit it into the pelvis.

The kits depend shape of the kits, just depend on what it is they're trying to treat the image.

On your left again is a schematic just showing a kind of way that this particular mesh fits behind the organs.

You can see here tends to be flat and very, very thin.

An ultrasound mesh has multiple ways that it can present.

These are the major ways that one can see or identify mesh.

It can appear as a short echogenic line, very similar to the suburethral sling except in this case, generally it's not in the position of the suburethral sling.

It can be a long echogenic line, multiple short linear echogenic lines, or it can be a dashed echogenic pattern.

The image here just demonstrate the appearance of both a sling and mesh.

Here is the symphysis anteriorly bladder, and then the urethra is right here.

Posterior to the urethra is the suburethral sling.

Here is the vagina, which has air, and then posterior to the vagina is mesh because this patient's had a prior vaginal prolapse.

Here you see this is a pattern of more of multiple short linear lines.

On the other view, the oblique coronal or transverse view mesh is very difficult to identify.

As I stated earlier, it's very, very thin.

Because it's so subtle, you have to be careful in terms of how you reconstruct your image.

Obviously in this case it's useful to have an experienced person doing that reconstruction.

In this case, the mesh just looks like a heterogeneous predominantly slightly more echogenic area compared to the surrounding tissues.

Abnormal Sonographic Conditions Causing Urinary Dysfunction

Now I'd like to turn to what are the types of findings you may see if a patient comes in and they're complaining of some kind of pelvic floor symptom.

First of all, many people, actually the most common symptoms we tend to see are that in are of the bladder.

If a person has problems with difficulty voiding or pelvic pressure, if a patient has difficulty voiding, one of the most common findings we see is that of cystocele.

Cystocele is merely a weakness in the bladder wall.

What we see here is the bladder wall pooches inferiorly and posteriorly.

This is the resting view.

But remember I said that on our exams we always do both a Kegel and Valsalva.

On the Valsalva here, you see the cystocele increases greatly in size.

Cystoceles are very common and it's something that you certainly should be able to easily recognize.

Another finding that you may see if a woman has urinary symptoms is that of bladder funneling.

In this particular case, in the resting view, things look pretty good.

Bladder looks fine. There's no particular cystocele here.

Here's the urethra vagina rectum.

This person already has a sling placed, however, with Valsalva notice some of the urine backtracks or goes forward into the urethra.

This V-shaped area of fluid, that is what is called funneling.

Transperineal ultrasound also obviously can see structural abnormalities of the female pelvis.

In this particular case, the patient had bladder infections.

When we looked at the pelvis, what we noted immediately is behind the urethra there was a mass which contained a calcified structure and this appearance was consistent with a urethral diverticulum.

Later on, the patient also had a CT, which just confirmed what we saw.

Sonographic Appearance of Pelvic Organ Prolapse

Now I'd like to turn to the problem of prolapse.

Actually uterine prolapse is something that is really a clinical diagnosis.

On a physical exam, a gynecologist will see that the cervix is an abnormal position.

However, if the patient hasn't had a gynecologic exam or if there is a prolapse, it is important for you at least to be able to recognize it.

This is a case of prolapse.

Here is the bladder, this is the base of the bladder.

Here is the urethra.

In this case, notice that the cervix is much further inferior.

This is the perineal surface much closer to the perineum compared to the bladder base.

This is an obvious case of uterine prolapse.

On every single case, whether or not the patient has rectal symptoms, we always look at the rectum.

In this particular case, again, I'm gonna show you this is the symphysis, this is the urethra vagina.

In the rectum notice this is the anterior wall and there's a little bulge here on the resting view.

This is the posterior wall of the rectum.

With Valsalva that bulge increases.

This is a rectocele.

Rectoceles are very easy to see and generally they do increase again with Valsalva.

Postoperative Complications After Surgery

In my practice, actually the vast majority of patients are coming to us because they have some kind of possible postoperative complication.

Unfortunately this group of patients has received a great deal of publicity in the press and in the legal societies.

Actually in our area, there are law firms that advertise for patients.

It's certainly an area that you should be very familiar with and be very careful whenever you do these exams.

The symptoms that one can have after surgery that might indicate a complication are listed on this slide.

The most common symptom is that of pain.

You could see about a third of the patients that have complications have pain.

Other symptoms include bleeding, dyspareunia, urinary problems, and neuromuscular or bowel problems.

The type of imaging findings that you will see or may see with ultrasound, again are listed here on this slide and I'll be showing you some examples.

They include erosion or perforation of the sling or mesh into the pelvic organs.

This is the most common complication. It is about 35% of all complications that one sees.

Other complications include fragmentation or displacement of the sling or mesh fistula formation, infection scarring or recurrence of prolapse or incontinence.

This is a 73-year-old woman who five years prior had had surgery and now comes back with multiple urinary tract infections.

On her exam it's clear she's got an abnormal bladder because she has a cystocele, large cystocele.

But she also has something else here is this echogenic material extending into the bladder.

This unfortunately is a fragment of her previous mesh which had been placed.

This is also probably the reason for her symptoms.

Noted that this is the most common complication one sees with postoperative in the postoperative area.

The second woman had very similar presentation with pelvic pain after surgery.

In her case, this is an oblique coronal exam.

This is the bladder. And on the right side of the bladder notice we see multiple short echogenic lines.

What these are, are these are fragments from her prior vaginal sling and mesh.

Even though these fragments haven't perforated an organ, they commonly cause inflammatory response, especially at these edges and so are associated with pain.

It is important that if you see fragmentation that you tell the urologist this.

This next patient had urinary leakage.

When we did the transperineal exam, we noted that there was a suburethral sling.

This is the urethra, the vagina just behind.

When we looked at it closer, so this is a closeup shot, we noticed that unfortunately this sling had actually perforated the urethra into the vagina and so had caused a urethral vaginal fistula.

Ultrasound, because we see this synthetic material so well is a great way to be able to problem solve and tell a urologist if there're going to be any problems that they need to try to adjust.

This next patient actually came in primarily with urinary problems and she does have urinary problems.

In other words, on her bladder you notice that she forms a little cystocele with Valsalva.

However, because of the appearance of the rectum, I then started asking her about her bowel movements and immediately she said, oh yes, after she had her surgery she started having real problems being able to evacuate her bowels.

The reason I ask that is because on the resting view, this is what you see.

Here's her anterior rectal wall and notice that it angles down right here.

It turns out she'd had a previous rectocele repair as well as mesh surgery for her urinary issues.

With the Valsalva right at the area of the angulation, there is this little outpouching of the rectum.

She has a small rectocele and for her that was significant because it changed the angle of the rectal canal such that it partially obstructed any kind of fecal material that might leave.

That's the reason for her symptoms.

Role of MR Versus Ultrasound in Pelvic Floor Disorders

Finally, I'd like to discuss the role of MR versus ultrasound in pelvic floor disorders.

All of us know that ultrasound is less expensive, painless, and very well tolerated.

We don't have to worry about patients having claustrophobia.

Ultrasound furthermore is excellent in identifying synthetic materials much better than MR.

MR studies which have been done in vivo show that these materials are very difficult to identify.

Furthermore, ultrasound is better in identifying movement.

If you have some kind of dysmotility, as I've shown you in the slides, we are really an excellent way to be able to show that in real time.

But MR definitely has a place in pelvic floor disorders and what we found in our experience is these are the areas that we particularly like to do MR.

First of all, we find that MR is better in identifying abnormalities in the retropubic portion of the pelvis as well as anterior to the sacrum.

Remember the symphysis, whenever we look at the symphysis, there's always some shadowing posterior to the symphysis.

That area just posterior to the symphysis is very difficult for us to evaluate.

Furthermore, anterior to the sacrum is just too deep.

We just cannot see it.

Abnormalities then, which are in those particular regions are much better identified by MR.

MR also is better identified if the patient has had human tissue types of materials used for their sling.

Because what happens to us is if a patient has a human tissue sling, it blends in with the rest of the tissues of the pelvis.

We really don't define it as well, whereas MR is able to define it much better.

Next, MR is better able to, or at least is prettier, let me put it that way.

Clinicians really like MR in being able to show them the low position of organs in the pelvis.

The reason is because it's got this wide field of view, you can see the bony landmarks and it's something that they can sort of visualize well and I'll show you an image of that.

Then finally there are some surgical complications which are very subtle for ultrasound, which are probably better identified by MRI.

These images, these schematic images are just to emphasize some of the areas which are relatively blind to ultrasound.

In this particular image, this is a, the black area is where mesh would be placed for a sacrocolpopexy and notice that the mesh is placed way up high on the sacrum.

This area, frankly, we cannot see, this is not an area we can see, we can visualize this region well, but when it comes to anything abnormal up here, we have to defer to MR.

The other areas I stated before is right behind the symphysis because many a times there's just too much shadowing in that area.

This is an example of a 48-year-old who was transferred to our institution after she just had an ileal tibial band, a human ileal tibial band sling placed.

Unfortunately after it was placed in an outside institution, the patient stopped being able to urinate.

This is an MR showing her pelvis.

You notice this low intensity band that's the iliotibial sling.

On the parasagittal exam, this is the level of the sling.

Notice this is the urethra and it angulates very sharply where that sling was placed.

It's very clear that in this particular case, the problem the patient has is due to a sling which was placed too tightly.

This image is just to show why a lot of urologists really like MR.

Now we can do measurements and certainly, from our point of view we can definitely say and tell a urologist without a doubt which organs are abnormally low.

However, this picture for many people is just worth more.

This is the pubococcygeal line from the inferior symphysis to the sacrum.

On the rest things don't look too badly, but with Valsalva notice that there's quite a bit of dropping of the pelvic organ.

This is a very pretty image.

The next case is a woman who has pelvic pain and on her MR, she had a small amount of fluid in her groin and that tracked back to the pelvis and there's not much fluid in the pelvis.

This patient had a urethral sling.

For ultrasound, we could find this area in the groin, that's not a problem and we could even see a little track.

The problem is here if there isn't much fluid around the device around the synthetic material, it's hard for us to define whether it's actually infected.

MR then it can be very useful in these more subtle infection cases.

In this particular case, it's similar except that this particular sling, the sacrocolpopexy sling is one which we, as I stated earlier, have a difficult time visualizing.

In this particular case we see that there's increased intensity of the sling in the pelvis.

It tracks up the anterior aspect of the sacrum.

As I stated, this is an area which we just don't see well.

This is an area where MR is better than us.

Conclusion

One conclusion, I hope I've shown that ultrasound transperineal ultrasound is an excellent method to evaluate patients with either symptoms of pelvic floor dysfunction or signs of complications.

The optimal ultrasound evaluation does include besides 2D, ultrasound, 3D, ultrasound and cine sonography.

Finally, MR is complimentary to ultrasound in certain circumstances such as slings composed of human tissues, low position of pelvic floor, and certain subtle surgical complications.

Thank you.