Pediatric Emergency Ultrasound - SD

Introduction to Pediatric Emergency Ultrasound

My name's Brian Coley.
I work at Nationwide Children's Hospital in Columbus, Ohio.
And today we're going to talk about pediatric emergency ultrasound.

The topics we're going to focus on today are the vomiting child dealing mainly with pyloric stenosis and malrotation, abdominal pain focusing on appendicitis and intussusception, and then pelvic pain talking about ovarian pathology in girls and testicular pathology in boys.

With any imaging, we want to identify pathology, arrive at the diagnosis efficiently and minimize discomfort.
And for pediatric patients, ultrasound is really the ideal modality of choice.

The Vomiting Child

When you have a vomiting infant, there are two main categories of disease.
There are medical causes, predominantly GER reflux, gastroenteritis or formula allergies.
But we're going to talk about surgical causes primarily, particularly pyloric stenosis, which presents with non-bilious vomiting and malrotation with or without midgut volvulus, which can present with bilious vomiting.

Pyloric Stenosis

Pyloric stenosis is very common.
It is four times more common in boys.
It's always said it's more common in the first born, realizing that there are more firstborns than anybody.
So everything is more common in firstborns.
It does run in families.
Interestingly though, it's more common in boys.
If your mother had it, you are more likely to have it as a child.

Pyloric stenosis hypertrophy of the muscular channel, and it really occurs between the ages of zero and three months, most commonly around six to eight weeks.
These children present with non-bilious projectile forceful vomiting.
If it's gone on for a while, they may be dehydrated, have weight loss, poor urine output, sometimes on the stomach.
In a more advanced case, you can see hyper peristalsis as in this child.
Here you can see waves of contraction across the abdomen.
And occasionally you can actually feel the hypertrophied pyloric muscle, which is referred to as an olive.

To do an ultrasound for pyloric stenosis, you want to use a high frequency linear transducer is preferable warm gel just for patient comfort and cooperation.
And you're going to scan the right upper per quadrant.
And somewhere between the supine and a full right lateral decubitus position, you're going to be able to lay out the pyloric channel, whether it's normal or abnormal, you have to have fluid in the antrum, and I'll show you pictures of that because that helps to distinguish.
The antrum from the pyloric channel.

Criteria are varied.
These are the ones that I use.
Unilateral muscle wall thickness of greater than three millimeters.
Some people use three and a half, some people use 2.5.
Those are the most reliable things.
However, the unilateral muscle thickness, pyloric channel elongation is less reliable.
I use 16 millimeters.
Other authorities if you used other numbers, but again, it's really the unilateral muscle thickness is the most reliable finding.

Now, when you have a normal pylorus, things are very easy.
So in this particular case, we have fluid in the stomach.
It is right here in the dark liquid separating the walls of the antrum.
This is the duodenal bulb, and the pyloric channel is very narrow.
Okay? It's very short. It's not thick.
And this is the muscle that we're looking at this hypoechoic band at real time.
When you're watching, it's easy to see fluid move through the antrum through this narrow pylorus, in this case, shooting out into the duodenal bulb.
The duodenum is not dilated.
This is a normal examination, and you can see the normal relationship of the superior mesenteric artery right back here, where the pointer is and the superior mesenteric vein.
Okay, this is a normal relationship, which we'll get into with malrotation.

When you have pyloric stenosis, you can see on this child very clearly, there is a marked thickening of the pyloric channel.
It is elongated.
The mucosa here is this echogenic material tends to get a little bit thick.
You may get some pushback of the mucosa into the antrum.
The so-called target sign here is another case, very thick muscle of the pyloric channel.
This is the duodenal bulb, which is actually deformed by the hypertrophied muscle.
This would be the sonographic equivalent of the upper GI mushroom cap sign.
Here's again, this little mucosa pooching back into the antrum of the stomach.
And again, the transverse image shows marked muscle thickening.
There are multiple channels through here.
Again, hypertrophied mucosa getting compressed.
This might be sort of the double track sign that you can read about with upper GI.
Harris Cohen has written a lot about this particular sign.

So what are some pitfalls in the examination?
If there's no fluid in the antrum, it can be difficult to tell a collapsed antrum from an elongated pyloric channel.
If you let the child have too much fluid in the stomach, it pushes the pylorus posteriorly, and it can be difficult to evaluate.
And when that happens, you can wait, or you can try a prone scan and I'll show you an example of that.
And lastly, you can have pyloric spasm where the channel will be long, but it tends not to be as thick as in real pyloric stenosis.

So in this child, we haven't rolled him up on his side, he's looking supine.
We do have some fluid over here in the antrum, but you can see my sonographer here is measured and elongated channel, but it's not thick.
And as we roll the child up and get that fluid to go into the antrum, you can see that eventually the whole pyloric channel opens up.
This muscle thickness is only about 1.5 millimeters fluid and air is seen to pass through, and this child is completely normal.

Now, here's a child. If you get one who's does have pyloric stenosis and they're very thirsty, and you offer them a bottle, they may drink this down very quickly.
And when that happens, you can see that the pyloric channel starts to turn.
So instead of being oriented this direction, it's turned posteriorly.
Or in the case on the right, it's even pointing the other direction.
Now, certainly that doesn't look normal, but it's hard to get a nice picture to convince the surgeons that this child has pyloric stenosis.
So again, you can wait or you can turn them over.
And here we're scanning through the back.
Here's tip of liver. Here's kidney.
And we're able to see the pylorus very nicely.
See that the muscle thickness is well over three millimeters, and the channel is well over 1.6 centimeters in length.
And you've now made the diagnosis much more efficiently in this child with vomiting.

Again, there's fluid in the antrum, but the pyloric channel is elongated.
Okay? It's 1.3 centimeters, but the muscle's not thick.
And we're not particularly suspicious.
But still, you have to prove that this opens up and that fluid moves from the antrum into the pylorus.
And this may take 10 or 15 minutes of waiting, but it's well worth it.
You don't want to send the surgeons in on a normal case.
And here things have opened up.
Here's our normal pyloric channel.
It is short, it is not thick. And here's fluid moving into the duodenal bulb.

In a normal examination, the surgery for a pyloric stenosis is a pyloromyotomy.
It's a longitudinal splitting of the pyloric muscle.
It doesn't fix the pyloric stenosis, but it relieves the obstruction by letting the lumen expand.
This is the mucosa that will pop through and this will eventually scar over and heal in just fine.

Midgut Malrotation

So midgut malrotation is a little more serious condition.
It's an anomaly of rotation of fixation during development, and you have an abnormal duodenojejunal junction instead of in this child with upper GI.
Instead of the duodenojejunal junction being at the level of the duodenal bulb to the left of the spine, it's much too low.
And the importance of this is that means you have a short mesentery.
And if there's a short small bowel mesentery, that intestine is more prone to twist and to cause an obstruction and ultimately even can cause intestinal ischemia.

These children usually present in the first week of life, although they can present at any time.
These kids are typically ill with bilious emesis, they have varying degrees of duodenal obstruction.
And depending on the severity of the volvulus and how long it's gone on, varying degrees of intestinal ischemia.

So while this is typically a diagnosis for upper GI and not ultrasound, there are things we can tell with ultrasound.
And I think it's worth looking at in any child with vomiting.

Normally, as we saw, the SMA and SMV are positioned such that the SMA is posterior and to the left of the superior mesenteric vein.
When you have malrotation, these relationships change.
And typically we have the SMA to the right of the SMV.
Now, this is not universal, unfortunately.
There are false positives and negatives.

Other things we can look for are a fluid-filled proximal duodenum indicating obstruction or a mesenteric whirlpool sign, which shows the rotation of the vessels.

So in this particular child who came to us with non-bilious vomiting, we had a normal pyloric stenosis study.
But a part of our routine is to look at the position of the SMA and SMV.
Now, you don't even have to bother doppler.
The SMA always has this little echogenic collar of fat around it, no matter how skinny the child.
Okay? There's always this collar of fat.
So this is the SMA, and this is the SMV.
And this is an abnormal relationship.
The SMA ought to be over here, not over on the other side.
And sure enough, when we take this child over to fluoroscopy, the duodenal C loop, instead of coming up to this level, which would be normal rotation, it's much too low.
You can even see there's a little bit of bowel dilatation in this child with malrotation and intermittent volvulus.

This child also had volvulus, we were, this was an earlier case where we weren't routinely checking the SMA and SMV, but you can see that the duodenal bulb is abnormally dilated.
So again, while I may not know the cause, this child has a post pyloric duodenal obstruction and an ill child with bilious vomiting, you have to assume that that's midgut volvulus until proven otherwise.

The whirlpool sign is shown here in this child.
This is a typical upper GI finding of midgut volvulus, where you'll have the SMA down the center of this corkscrew with the vessels wrapping around it.
And here on a transverse ultrasound image, here is the SMA in the center with the SMV and azygos vein surrounding it in this sort of corkscrew or whirlpool appearance.

Here's another case more recently from our department.
Here's the color doppler with these distended dilated veins around this SMA.
And as you work your way up and down while you're ultrasounding, I think you can get the idea that there looks like there's a whirl or a target or a bullseye here.
And again, we are looking at the wrapping of the mesentery around that central core containing the SMA.

Unfortunately, if you have normal anatomy by ultrasound, you may still have mal rotation up to 3%.
So ultrasound cannot exclude mal rotation.
There are some newer works suggesting that if we can see the duodenum passing behind the superior mesenteric artery, that may conclusively exclude malrotation or at least indicate normal fixation.
Those studies still need to have some validation.
They are not conclusive yet, and you still need an upper GI as the bottom line.

However, when you're doing your due diligence in trying to find the cause of vomiting in a child, do look at the position of the SMA and SMV.
It may give you indications that you need to go further.

Abdominal Pain in Children

Abdominal pain in children has many causes.
In many cases, never arrive at a specific diagnosis.
We are generally asked to get involved to try to discern between medical or surgical disease.
Imaging plays an increasing role, so much that at least in some developed countries, you can often wonder did anyone examine the patient?
'Cause as soon as the patient arrives at the physician's office or emergency room, imaging is thought of as a first step toward diagnosis.

Appendicitis

Appendicitis is still the most common cause for emergent surgery in children.
There's an incidence of roughly four in a thousand with an eight to 9% lifetime risk.
The classic symptoms are periumbilical pain, moving down to the right lower quadrant associated with fever, nausea, and vomiting.
That said, there are often atypical presentations.
And the younger you are, the more difficult the examination becomes, the less certain the symptoms are.
So it can still be a vexing problem for the clinicians to decide which child has it and which child doesn't.

Lots of ways to image appendicitis.
Ultrasound versus CT are the primary ones.
There's a lot of controversy about which is best, issues of radiation and expertise, preparation time, and how many alternate diagnoses you may arrive at.
That's for another day.
But suffices to say ultrasound should be the first line of imaging for children with appendicitis, because while we can have some very large children, which can make it difficult, it's still very useful.

You need to use high frequency linear transducers and use the graded compression technique to push air-filled bowel out of the way to let you see into the depth of the pelvis, find the cecum.
Pain may limit the examination.
Some children, you do have to push hard though.
If you go gently, you can usually overcome their resistance.
And many appendices are retrocecal, so that can make them more difficult to see.
And again, if you do not use graded compression, you really will have no chance of finding them.

People have different methodologies.
I start off with asking the child, where does it hurt?
And they get to show me with one finger. Okay?
They don't get to point to a whole area.
They show me with one finger.
And if that's, if they can do that, then that's where I start scanning.
Alternatively, if they can't really find defined for me one particular point, or if I don't see anything when they do point to that, I tend to identify the ascending colon.
I then move inferiorly down to the toward the iliac pole.
I find the terminal ileum and the ileocecal valve.
And I know that the appendix lives slightly inferior.
So if I keep scanning more inferiorly, eventually I'll find the base of the appendix and then I can go from there.

So again, gentle graded compression.
First, scan around with light pressure, get a lay of the land, get the child to trust you a little bit, and then slowly increase pressure.
And it's important not only to watch the screen, but also something can learn from surgeons is watch the patient, watch the patient's reaction while you're scanning.

There are some maneuvers that can improve detection.
And the referenced article, there was a nice study.
You can do posterior compression, you can press in and press up.
We typically use a scan these children with an empty bladder, but occasionally, especially large kids, you can actually use the bladder as an acoustic window.
Sometimes you can roll a child up, you can use a curved array transducer on larger kids.
But of all the maneuvers I found, this one where you push up posteriorly as well as down, can really push air out of the way of the ascending colon and gives you a great view of the retrocecal colonic gutter to look for appendices back there.

So what's a normal appendix?
Six millimeters is still the norm.
How often you see it really depends on the size of your patients, your experience, how long you're willing to take.
I think we see it now in upwards of 75% of children.
When first starting out, I probably only saw it about 10% of the time.
Even if you don't see it, document your landmarks, document the SOAs document, the iliac vessels show that you were in the right area.

The value of a negative appendix ultrasound in kids is a matter of debate.
My opinion is that if I've got no abnormalities, I have no hyperemia, everything looks normal, that's a pretty reliable sign.
And there is literature out there that suggests that the negative predictive value of a normal ultrasound, even without seeing the appendix, may be well above 90%.

The normal appendix should be compressible, can contain gas or fluid, but you should be able to press it as in this case where we have a nice normal appendix.
It's small.
It has a normal gut signature with the different layers of the wall.
And as you compress, you can completely collapse it.
In this case. Here's the same patient on a longitudinal scan.
Nice normal appendix. You see the tip?
Well, there's no surrounding hyperemia, normal gut signature in this case.

Again, here's a normal appendix.
You see the blind ending tip.
No hyperemia, no surrounding inflammatory change, normal size.
Here's another case. Nice normal appendix sitting on top of the iliac vessels here.
Another normal appendix, slightly older case.
Again, no surrounding inflammatory reaction.
This one, while you may think it looks more concerning, remember they can fill with fluid.
And in the old days doing barium enemas, remember that most normal appendices, 90% fill with barium.
So it's okay to have luminal contents.
Again, normal GI wall, you see the layers.
Well, there's no surrounding hyperemia or inflammatory change, and this is just a normal appendix.

Another one, the degree of hyperemia really depends upon your machines.
And with technology changing, you know, what's normal is it constantly moving targets.
So you have to be aware of with your own equipment and your own particular transducers what a normal amount of blood flow should be within the appendix.

So an abnormal appendix typically is larger than six millimeters.
It's not compressible. You may see an appendicolith.
You have hyperemia with color doppler, and I think a very useful sign is adjacent fluid or adjacent induration and inflammatory change in the fat.
I found that one of the most reliable things to look for.

So here is a inflamed appendix.
It is certainly larger than six millimeters.
We still have the normal GI wall.
We haven't lost that, but look at this abnormal echogenic fat adjacent to it.
So this inflammatory change adjacent to the appendix can be a really good tip off if you had any doubt about this.
This is an abnormal appendix and the operative photo.
You can see this very large inflamed appendix right here.
Again, echogenic fat. Here's the appendix.
There's a little bit of fluid around it, but in the transverse image, you can see all this abnormal echogenic fat indicating inflammatory change in the periappendiceal soft tissues.
Color doppler in this case, or power doppler here shows tremendous hyperemia on the wall.
You may not have uniform thickening, but again, we have nine millimeters.
This is non-compressible hyperemic.
Little bit of reaction around it in this child with acute appendicitis.

More cases, again, transverse image, not compressible, they will not like it.
When you do this compression, it certainly hurts, but it's a nice confirmatory finding that you do in fact have appendicitis in this case.
There is some hyperemia.
The lumen or the appendix is swollen to almost nine millimeters, no abscess, just a simple acute appendicitis.

As the inflammation goes on, the appendix can start to become gangrenous and necrotic.
And so in this case, we certainly have an enlarged appendix, but it's fairly featureless.
Look at this normal loop of distal ileum right here.
You can still see the bowel layers.
So we know it's not a technique problem, but the appendix immediately posterior to it is enlarged losing mucosal detail.
Very patchy blood flow in this child with acute gangrenous appendicitis near the point of perforation.

Again, no hyperemia. Okay, don't be dissuaded by that.
This is a completely necrotic in a larger child infarcted appendix, completely gangrenous.
So we wouldn't expect blood flow.
And in this case, we really lost really all mucosal detail.
There's just little bubbles of gas here in the lumen, probably actually in the wall of the appendix.
Lots of inflammatory change in the surrounding fat.
And this child had a completely necrotic and early perforated appendicitis.

It really is important to see the whole thing.
You can have appendicitis just located to the tip, as in this particular case.
The proximal appendix was normal.
There was an obstructing lith roughly here.
And so the appendiceal tip is dilated.
The patient was exquisitely tender.
There a little bit of inflammatory change around.
And in this machine, this was hyperemia back in the day for this particular scanner in this child that had appendicitis just located to the tip.

Look around for appendicoliths, particularly in the day of laparoscopic appendectomies.
You don't want to leave an appendicolith behind.
If they leave it behind. The child will almost always get an abscess and require a second operation.
And liths can be of various sizes and various degrees of echogenicity from rather small with a minimal posterior shadowing to very large stones indeed, which obstruct the entire lumen near the base of the appendix.

And lastly, always look down at the cul-de-sac for abscess again, now that you've made the diagnosis, now our job is to try to inform the surgeons and the clinicians.
What sort of treatment is possible if you have a large abscess or at least have concerns about that, that child may benefit more from interventional drainage in an interval appendectomy after the abscess and infection has cooled down, if you don't see an abscess, and the surgeons may elect to do a primary operation.

So overall papers are fairly consistent.
The sensitivity of ultrasound for diagnosing appendicitis is roughly 85%.
Using color doppler I think helps.
Looking for those inflammatory changes in the right lower quadrant also helps.

False negatives can occur with a focal or very early appendicitis.
If it's retrocecal, if it's perforated and decompressed, it may be more difficult to find.
You can have false positives with Crohn's disease or Meckel's diverticulum.
I don't feel bad about that would still be a surgical indication.
But occasionally you can get Crohn's disease as this patient has here.
And this is really, this is a thickened loop of distal small bowel, markedly thick, lots of inflammatory changes around it.
Lymph nodes, again, if you scan around, you'll see other abnormal loops of bowel.
You won't just find an abnormal appendix.
So this should not typically be a major complicating issue.

Intussusception

Intussusception is another very common cause of abdominal pain, or at least a concern to the clinician.
It's an invagination of the bowel into itself.
Ileocolic occurring near the ileocecal valve is the most common.
Most of these kids are younger than two years of age, and it's very uncommon, less than three months of age, primarily because lymphoid tissue, the Peyer's patches in the distal small bowel typically are the lead point after a viral illness and below three months of age.
Typically children don't have well developed enough lymphoid tissue to act as a lead point.

Over 95% of these are idiopathic.
Occasionally you can have duplication cysts or a Meckel's diverticulum or some other mass as act as a lead point.
Those children are usually older.

The classic triad of intermittent abdominal colicky pain mass and bleeding with the so-called currant jelly stools.
While classic, like many classic triads is present in a minority of cases, plain radiographs I think still have some role in looking at the child with abdominal pain in this particular patient.
Not a grossly abnormal bowel gas pattern, but there is some slightly dilated loops of small bowel here.
You have to get some sort of a decubitus film or prone image to get air to go up into the ascending colon.
And in this case, we see this rounded soft tissue mass, which is the intussusception.

Now, while plain films are still rather useful, ultrasound has terribly high sensitivity and specificity for intussusception.
It's probably as close to the perfect test as anything we have in pediatric ultrasound.
If you know what you're doing, you can easily see these intussusceptions.
They have a pseudo kidney appearance with multiple layers.
Several authors are looking at whether it's worth assessing bowel viability to see if children are candidates for intussusception reduction, either by fluoroscopic or ultrasound means.

We use a high frequency linear curved probe.
You really need to search for the entire abdomen.
Most will be found on the right side.
You can use gentle compression.
But again, when people are starting out, they worry that the colon is typically full of gas.
How will I see it if it's there?
But remember, if you have this big mass, which is invaginated into the intestine, it's going to displace all of the gas and you'll see the mass and it's really not a problem.

So in this particular child, here is a longitudinal view.
Here's the kidney. The child has a little bit of free fluid.
This is the pseudo kidney appearance, regular kidney, pseudo kidney, and a transverse image of the same patient.
Here's more of the target or bullseye sign, again, adjacent to a normal kidney.
Another picture here, this is the intussusceptum, the recipient or the thing the bowel invaginates into here is the intussuscipiens, the inner part, which is coming in.
And you can often see this echogenic material.
This is the mesenteric fat that supplies the intussuscipiens.
So this, it's the fat that goes along with this loop of bowel.
You may see lymph nodes, okay, not the same case, but here are little lymph nodes, a path specimen showing the intussusceptum, the intussuscipiens with associated fat.
And in this case a mesenteric node, probably acting as the lead point in that case.

Color doppler the slightly older study.
But it's borne out by newer research as well that if you see blood flow that indicates bowel viability, and that indicates that reduction could certainly be successful.
Absent blood flow to me is not a contraindication to try an intussusception reduction because again, if you don't try it or a successful, a child's going to need an operation.
So in my opinion, there's little to lose.
It's still worth looking at the blood flow to see if the bowel is viable.
'Cause that can certainly indicate that you may have problems afterwards and that the parents and surgeons should be aware of potential complications.

So the treatment, again, is a reduction enema.
We use air in our institution.
I think it's safer than liquid media.
The success rate should be over 90%.
That really depends upon the duration of how long the disease has been there, whether or not there's a lead point.
And again, if we are unsuccessful, the child's going to need surgery.

So just a couple of fluoroscopic spot images from a reduction.
Here is the intussusception up here.
We are filling the colon with air.
We are pushing the intussusception back here.
We have pushed it back to the ileocecal valve and finally popped through.
And you can now see filling of loops of small bowel and disappearance of the mass in that successful reduction.

If they're not successful, they will have to have an operation.
So here is the cecum and here's the surgeon pulling out the distal small bowel from the ileocecal valve.
And while this particular bowel is a little bit dusky, it certainly pinked up.
There was no necrosis and the child did not need any sort of bowel resection.

Intussusceptions can recur.
We usually quote an incidence of roughly 5% to parents in this particular child on August 10th, came in, had classic intussusception findings, had a successful reduction, went home, had recurrent symptoms, and came back in the next day with the exact same ultrasound appearance.
We looked again, did not find any pathologic lead point, which is something you probably should do in a child with recurrent intussusception, although most won't have it.
This particular patient had another successful reduction and then had no more further problems.

Acute Pelvic Pain

So basically that'll be ovarian issues in girls and testicular issues in boys.
Not surprising.
Ultrasound really is the most useful modality for pediatric gynecologic imaging.
Most of the time we're doing transabdominal images.
So you need a full urinary bladder, whether you do that with oral hydration, IV hydration, or putting a Foley catheter and retrograde filling depends upon how soon the information is needed and how well your patient can tolerate having a full bladder.

Don't forget to do transvaginal scanning.
If the girl is sexually active, if she uses tampons, this is a viable alternative.
It's well tolerated and it can certainly save you time by not having any bladder preparation.

Ovarian Pathology

The most common thing we see are just simple ovarian follicular cysts that these can cause pain in this particular child.
There's a large left dominant follicle.
This may have a little bit of internal hemorrhage within it.
These things certainly can cause pain, especially when they rupture.

My favorite case here is this child was in our department.
We were doing an ultrasound.
She was having pain that was in fact localized to the side with the dominant follicle.
As a sonographer came out to show the images to us.
There was a cry of pain from the room.
We went back in and re-scanned, and now there was all of this free fluid within the cul-de-sac, which was not there before.
And this child ruptured her cyst right in the middle of our exam room.

So even though it's a small cyst, certainly cyst rupture can cause a very large amount of fluid, probably from the cyst and some subsequent hemorrhage.
So look for that. These are the most common causes of pain.

The thing that the emergency department is usually most worried about is ovarian torsion.
And these are most common in the younger child around puberty and young adulthood.
Acute onset of symptoms like with testicular torsion.
Many of these girls will have a palpable mass.
Many of 'em will have had prior episodes of twisting and pain.
And certainly if you have a large cyst or a tumor that can predispose to ovarian torsion.

This is a in utero torsion, a child with a cystic mass seen in utero was born.
And we see this complex fluid-filled cyst with a debris fluid level.
And down at the bottom there was this kind of swirling pattern down toward a central pedicle at the base of this mass.
And at surgery, I think you can see here is the pedicle, the torsed necrotic ovary.
And we were seeing this sort of swirling of the base as it came down into this twist.

So that's been described.
I haven't seen this frequently, but again, it's something you can look for to help narrow your diagnosis when you're doing scans in these kids.

The most reliable sign for a torsed ovary is a large ovary.
And several good papers have come out recently showing that torsed ovaries are typically four times or 10 times the size of the contralateral ovary.
The classic is a large ovary with peripheral cysts thought to be fluid pushed into nascent follicles.
Often you'll have some cul-de-sac fluid that's clearly not specific.
And again, while we doppler these ovaries looking for flow, do not be dissuaded if you are able to pick up some arterial flow because of the dual supply from the ovarian and uterine circulations.
Even if you have a torsed ovary, you may still be able to get demonstrable arterial flow.

So here's a classic case in a teenage girl with acute pain.
We have a very large ovary with peripheral follicles.
And here's the normal ovary comparison for comparison.
Certainly this thing is grossly enlarged and not much doubt about the diagnosis.

This child also had acute pain, had a rather complex looking ovary, maybe some peripheral follicles.
We did not see any calcification or fatty mass.
This kind of looks like a fibrillated end of a fallopian tube to me.
And here's a laparoscopic picture showing the uterus down here with the broad ligaments.
Here is the torsed fallopian tube and here was a large torsed necrotic cystic teratoma.

In this young girl, you have to have a high clinical suspicion.
If you have an ovary like this, you may not be able to have a specific diagnosis, but if you're going to have any hope of salvage, the surgeons have to be willing to go in and you have to be willing to raise the diagnosis.
Classically, the salvage rate has been very poor, roughly in the order of 10% in the era of laparoscopy and a little more aggressive surgical treatment, at least at our institutions, the salvage rate is probably above just above 50% right now.

Another problem is that since these are intraabdominal, they can have rather a delayed presentation because of what are felt to be non-specific symptoms that are often attributed to GI tract disease.

Testicular Pathology

For the acute scrotum, the number one concern is testicular torsion.
And the classic mantra is that if you think it's torsion, the child should go directly to the operating room without going to any sort of imaging.
And the reason for that is that if you're going to salvage the testes, you have to get to them early.

So this classic paper showing that if you operate over 12 hours from the onset of symptoms, the odds of salvaging the testicle drop rapidly in over 24 hours.
The salvage rate is essentially nil.

And so while testicular diagnose testicular torsion is a clinical diagnosis, it's clear from the literature and experience that most children that present with acute scrotal pain actually don't have it.
The exam can be unclear in those that do have it, and it can be a very litigious area, at least in the United States.
And all that put together means that imaging becomes very important in the diagnosis.

Ultrasound with doppler is the standard.
Very few places use nuclear medicine anymore.
Gray scale color doppler or power doppler, and you have to find a waveform.
You have to prove that there's arterial flow to the testicle.

Now, while the gray scale is said to be unreliable for torsion, there are very few cases.
In fact, I can't think of any where there's been testicular torsion and the gray scale has been completely normal.
So we'll go through a few of these findings of transversely twisted spermatic cord, bell clapper deformity, and paratesticular mass.

So in this case of torsion, we can see flow in the normal right testis and no flow in the torsed left testis.
But look at the labels.
So these are long relative to the scrotum.
And on the right, the normal side, the testis has a longitudinal view as you would expect.
However, when you're looking at the torsed left testis, while the probe may be longitudinal, we really get more of a transverse view of the testis.
And that's because as it torses and twists and rises, it rotates.
And so it has an abnormal lie within the scrotal sac.

You can also see there's some thickening of the scrotal skin, a reactive hydrocele, which while they are not specific for torsion, certainly it is another indicator that there is some abnormal process going on.

Looking at the spermatic cord itself is being increasingly recognized as a very sensitive way of diagnosing torsion.
So in this particular child, certainly we have an enlarged hypoechoic testis flow in the normal side, no flow in the painful side, but I think you can look at this and kind of imagine this sort of undulating course of the cord.
And when you put color on, there's flow in the cord all the way down right to the testicle, and then no flow whatsoever in this case.

Here, I think you can get a better appreciation of the twist of the spermatic cord as it comes down.
And again, you can see flow within the spermatic cord all the way down to the testicle, which has no significant perfusion.

This is a clip loaned to me by Gloria del Pozo from Madrid.
And I think as she's scanning transversely up and down the cord, I think you can get an appreciation that there's sort of a whirlpool sign, just like we saw in midgut volvulus.
As you move up and down the cord, you can see that these vessels wrap around the central part of the cord indicating that you've got a twist.

Testes torse, because they are not normally fixed to the scrotal wall.
And so the term is a bell clapper deformity where the testicle hangs within the scrotum like the clapper within a bell.
And this can be a difficult diagnosis, but if you do have hydrocele fluid and you scan very gently, you can probably demonstrate, as in this case, that there is fluid all the way around the testicle, that it is not attached in any way to the scrotal wall.
And the only thing that it is attached to is up here where the cord comes in.

Now this child had acute scrotal pain.
He's got enlarged testis compared to the other side.
But right now he doesn't hurt.
And that's a key thing that we'll get into.
His pain is better. He does have flow.
He doesn't have a problem right now, but this is abnormal.
This child has abnormal fixation.
And while he may not need an operation now, he certainly needs to go see the urologist to get pexy.
And he also needs to be aware, as does the family, that if he has recurrent pain, he has to come right back 'cause he is a setup for recurrent torsion.

This paratesticular mass has also been described.
You know, here's the testicle here.
Is this abnormal almost equally large soft tissue mass within the scrotum.
And this is going to be composed of the twisted cord, the swollen epididymis.

Again, color doppler is our key flow in the asymptomatic normal side.
No flow in the symptomatic torsed side.
Again, color doppler, this is your key. Okay?
This child has enlarged testes becoming a little heterogeneous.
You start to worry about viability when you start getting gray scale changes. Here's another case.
And then lastly, when you get testes that look like this, there is complete infarction.
You may have areas of hemorrhage, lots of hyperemia around it.
This would be the doppler equivalent of the nuclear medicine donut sign with hyperemia around this testes cold, no flow in the center.
And once you see this, that these children, these kids do not have salvage testes.

So what are some pitfalls in torsion?
Well, there's spontaneous detorsion.
Again, if you have a bell clapper deformity, you can twist and untwist and these kids will often have increased flow, which can be confusing.
Intermittent torsion and then partial torsions.

So a partial or an incomplete torsion is generally less than a 360 degree twist.
And in these kids you can have color flow, but it'll be less than on the asymptomatic side.
And while your waveform may be changed, you can also have normal looking arterial flow.

So this child came in with what the acute scrotal pain has an abnormal lie of the testis, okay?
Has this paratesticular mass, even has some microliths just for a bonus, has some surrounding hydrocele fluid.
But if you turn on color doppler, normal side has lots of flow, but this side also has arterial flow.
And if you are in a practice where you just trust on that as a sole sign, you're going to miss this case.
While I don't, I'm not going to show you the images, the waveforms, right?
Identical from side to side.
So this child had a 360 degree twist and was salvageable at surgery.
But if all you go on is just a binary decision of flow or no flow, you're going to miss these patients.

Here's another child. Less flow, but still we could get doppler flow in the symptomatic left testis.
Again, not a normal gray scale appearance, kind of an abnormal transverse lie.
And here's the arterial waveform, normal side on the left, abnormal side on the right, you can see reversal flow and diastole indicating venous congestion.

I do not typically look for venous flow.
I know a lot of people do, particularly in Europe.
I haven't found it to be a great discriminator.
But again, certainly this indicates congestion from occluded vessels before it goes on to have arterial occlusion and can be a useful sign.

So detorsion. Okay.
Typically you want to go counterclockwise.
If you're standing at the foot of the bed, you want to rotate like an open book.
And these pictures from the internet show a dusky testes.
Once it is unwrapped and the cord is no longer kinked, it pinks up and proves to be a viable testicle.

Here's a case that occurred in our department.
On the left you can see this very young child, normal testicle.
The left side here just has sort of color doppler chatter within it and manually detorsing this child 'cause it had been going on for about six hours.
The operating room was going to be a little bit delayed and you can see the tremendous increased blood flow after that detorsion.
And the child has immediate relief of pain.
This child certainly needs an operation but can at least afford to wait a few hours if need be.
And ultrasound can prove that there now is flow to this testicle and that the surgical emergency is at least vetted for some time.

Here's a corresponding nuclear medicine images showing the same thing.
And this child who is manually detorsed showing increased blood flow to the previously torsed testicle.

Now intermittent torsion is something to be aware of, and I think it's very important that you have to ask the patients, whether adult or child, what's their degree of pain when you're doing the imaging.

So this particular young teenage boy on the left came into our department several times over the course of 18 months.
And every time, or the first three times, he had images like you see on the left there.
So testicle was a little swollen, the epididymis was big, there was a reactive hydrocele a little bit of hyperemia.
And in one of the reports it even mentions that the child had less pain at the time of examination than what had caused him to come to the emergency room.

Now this child received appropriate urologic follow-up, had appropriate testing, everything was negative.
But the last time he had scrotal pain, he decided to stay away for a week since they never really did anything for him in the emergency department.
But unfortunately this is what the testicle looked like when he came in at that time.
And so now it's a completely dead necrotic testis.
And I'm sure that he was intermittently torsed and we failed to pick up on the symptoms.

So again, it's very important to consider the degree of pain.
If they detorse, they will have relief of pain.
And so it can look like an inflammatory condition, but in fact, you've got a detorsed testis.

Appendiceal torsion is the most common thing that we see in the prepubertal population.
Generally these are testicular appendages that twist.
They live right next to the epididymal ones.
You really can't tell the difference.
And if you can faintly see as you stretch the skin over these infarcted appendices, you can see this faint blue dot this discoloration beneath the thin scrotal skin.

If you look for them, you will find them.
They're almost always associated with a hydrocele.
These can produce tremendous hyperemia.
And in the literature, these are often called epididymitis.
And while it is an inflammation of the epididymis, it is not epididymitis in the classic sense of being an infectious etiology.

So in this particular case, a fairly typical appearance, you can see the torsed appendage.
They often have this heterogeneous described as salt and pepper appearance.
They're typically over five millimeters with tremendous surrounding hyperemia.
There's thickening of the scrotal skin, some dirty hydrocele fluid, and you can even get some associated testicular hyperemia, but tremendous inflammatory response.

Most common thing we see in prepubertal males, most of the time these will go away with just conservative treatment.
Occasionally they need to be operated on to remove these.

Here's just another case showing this torsed infarcted appendix with tremendous hyperemia in the scrotal wall and within the testicle.
Again, most of the time they don't need to be operated on, but if the pain is not going away in a week, they will operate.
They will lop off the torsed appendage causing this tremendous inflammatory reaction of the adjacent epididymis.

Later, as they shrink down, they will calcify into these little nubbins that you'll see on later imaging.
And these can actually float free within the scrotal sac and become these scrotal calculi.

One of my favorite clips in the world shows one of these flinging around loosely within the scrotal sac.

So again, the diagnosis of torsion is no longer a binary decision.
You have to consider the pain at the time of ultrasound.
So if you have a patient who's got hyperemia and increased flow and they have the same amount of pain they did as they came in, that's some sort of inflammatory condition.
Those children do not need surgery if they've got hyperemia, but they say, yeah, my pain is better.
I don't feel as bad, you have to consider detorsion.
And while that may not need surgery now they may well need surgery later.
And at the very least, very close follow up.

Summary of Emergency Conditions

So just as a quick summary for typical emergency conditions, a vomiting child and pyloric stenosis, you have to move the patient.
You may have to roll them up on their side to get fluid into that antrum, which is key at separating the antral walls and really defining the outlines of the true pylorus.
If their stomach is too full consider prone imaging, look through the back to help see the pylorus, which may be displaced more posteriorly.

Look for the SMA and SMV.
While it is not a perfect test, you can often be a hero and make the first indication that this child may have mal rotation with or without intermittent volvulus.

Appendicitis is still the most common cause of emergent surgery in children.
The graded compression technique in the use of color doppler and adjunct generally will lead to success in the vast majority of cases.
In spite of the current popularity of CT.
Ultrasound is still a useful tool and should still be considered the first line in imaging in any child with appendicitis.

Intussusception. Ultrasound is a very high sensitivity for finding intussusceptions in pelvic pain like in adults.
Ultrasound is the imaging modality of choice.
Cysts are very common. Torsion is what we are really worried about many of the times requires a high index of suspicion.
Remember that doppler waveforms are not completely reliable.
And look at the difference between the two sizes of the ovaries for pelvic pain and testicular torsion.

Remember that testicular torsion is not the most common thing, but it needs a rapid diagnosis, which is why we are called to image quite frequently.
Appendiceal torsion is the most common diagnosis.
Look at blood flow symmetry and consider the symptoms of the child when making your diagnosis.

Thanks for your time. I hope that's been useful to you.