Ultrasound in the Diagnosis of Clinical Complaints: Pelvic Pain in the Child & Adolescent - HD

Introduction

Hi, I'm Harris Cohen, originally from Brooklyn, New York, but I'm now chairman of radiology at University of Tennessee in Memphis. And radiologist in chief of Lab, Barnard Children's Hospital in Memphis as well.

Ultrasound and the Diagnosis of Pelvic Pain in the Child and Adolescent

Pelvic pain in the pediatric patient has gynecologic considerations, hemorrhagic cyst, uterine obstruction, ovarian torsion, teratomas, and other ovarian masses, pelvic inflammatory disease and ectopic pregnancy, which won't be discussed in this lecture.

It also has nine non gynecologic causes, whether in the gastrointestinal tract or the genital urinary tract, which can include appendicitis, Crohn's disease, meso, enteric, adenitis, ureteral stone or bladder infection.

All these entities, both the GYN non GNYN entities may be diagnosed by ultrasound in a world in which radiation safety is important, consideration of triaging and perhaps making the true diagnosis of patients using ultrasound first is very helpful.

Normal Ultrasound Findings in Pediatric Imaging

As with all pediatric imaging, normal ultrasound findings change over time, including the teenage years. Changes are affected by the child's age as well as her changing hormonal environment. One must be aware of normal and expected findings for the various ages of childhood.

Normal Volumes for the Ovary

What are normal volumes for the ovary? Some people use the formula for pro later lips, which is pi over six times width, times length, times depth PI over six equals 0.523. So some people simplify that formula and simply go width times length, times depth divided by two gives you the volume of an ovary.

The concept of what is normal for an adult and for a teenager has evolved during my lifetime in radiology. The classic three by two by one centimeter three cc volume discussed when I was a young attending underestimates by far the normal volume, which is now thought between six and nine cc and adults in mature teens. We use a 15 to 20 cc gray zones. We consider everything up to 15 cc in a teenager or adult who's not postmenopausal to be normal. We know that normal can be all the way up to 23 cc, but by tradition read 20 cc or greater as enlarged.

The pediatric ovarian volume increases at eight years of age and greater for unknown reasons. In great work by Ardian Orsini in the 1980s, they noted that Tanner three children had three CC ovaries and 10 or four four to 4.6 cc ovaries and 10 or five full. Post butal ma full post pubertal maturity, 10 or five full post pubertal maturity ran ovaries at five to 7.6 cc. And this was in the days when ultrasound imaging was not as good as it is now.

The concepts of normal ovarian size and morphology and the younger child have also evolved. In 1977, sample saw only one ovary among four girl patients and an average 0.7 cc, well, didn't average 0.7 cc, it was 0.7 cc in 1985. Stan hope noted in eight girls six months to two years that the mean ovarian volume at two years of age was about one cc, and that no six month to two year volume was greater than 1.5 cc, and that cysts and follicles were thought uncommon.

Now, there was a problem with this because one can see images like the one I'm showing you here, not uncommonly, in which this is a six week old, seven pound, 10 ounce girl, 22 inches in length, whose right ovary has a group of eChoice areas within it that look like follicle slash cysts. And this is another six week old with prominent cysts and a prominent size to their ovary. This ovary was two by 1.1 centimeter with the largest cyst, 10 millimeters.

So it was necessary to find out what the correct answer was with regard to what the normal pediatric ovary looks like, including the neonatal ovary. And it ends up, it's not a structure that is lying fallow, so to speak, particularly in the neonate.

The rise of gonadotropin FSH follicle stimulating hormone levels with a decrease in fetal estrogen and progesterone at the separation of the placenta gives a reason why cysts are seen within neonatal ovaries.

We studied the first two years of life and found that at zero to three months of age, the average ovarian volume was 1.1 cc, but we had a range going all the way up to 3.6 cc. As large as some people were saying an adult ovary should be in their, in the older incorrect analysis of this, and we noted 82% of the ovaries to be cystic in the four to 12 month age group with decreasing FSH levels. We still had a 1.1 cc average volume, but the range was 0.2 to 2.7 cc. Not as great as the zero to three month old age group, but again, cyst were seen and I'm using cys and follicles interchangeably, 13 to 24 months. The volume was 0.7 cc similar to what sample saw, and there was a range of 0.2 to 1.7 cc, but again, 80% of these ovaries that were seen, and perhaps we were biased if we didn't see a follicle, maybe we missed an ovary. But 80% of those ovaries we could see in three dimensions had contained follicle slash cysts. 16% of these cystic ovaries were macrocysts greater than nine millimeters, which at one point people were saying didn't occur in the first 10 years of life.

Volumes range volume ranges therefore are greater than once thought, with some of that background, we're now going to some clinical cases with pelvic pain.

Clinical Cases: Pelvic Pain

Hemorrhagic Ovarian Cyst

This is a 13-year-old girl with acute pelvic pain. This is a transverse image highlighting the right a NAL area and the uterus BL is a bladder, which technically you're seeing filled, but there was no debris in there. This is artifact. The debris filled cyst that one sees on the right side contains crisscrossing septations and a little bit of free fluid anterior and posterior to it. And do we have any thoughts about this?

So this is a pretty classic hemorrhagic ovarian cyst. It's not an uncommon cause of lower abdominal or pelvic pain in the adolescent. It's often a teenager's first complaint of pelvic pain. It's an important simulator of other abnormalities. It's image can simulate a two ovarian abscess in a patient with the appropriate clinical symptomatology and the image may be simulated by an endometrioma. Oftentimes not a problem in children and teenagers, but more so a concern in infertility workups and in workups of those with extremely significant menstrual pain History obviously is therefore very important.

Follicular cysts occur due to failed involution of a normal maturing follicle cyst en large because of temporary or persistent hormonal imbalance. It's the most common cause of an nexel enlargement. Its diagnosis is more difficult if there is a loss of the classic cystic image and a classic cyst is echos, has a sharp back wall and has excellent through transmission. But when there is hemorrhage due to the rupture of fragile wall vessels, one will see echogenic content to the cyst and hence the hemorrhagic physiological variant cyst can be seen at any age, including as a fetus, but typically hormonal causes begin with menarchy hemorrhagic ovarian.

Cys can develop in ovarian follicles at any stage in maturation, including as they undergo atresia. It may also develop in the corpus lutetium residual of the dominant graphene follicle and after ovulation resolution of pain and a stable amato allows conservative management with tincture of time allowing image resolution on follow-up ultrasound to help make the diagnosis.

Many of these cases that I've seen in my life are in individuals who have just begun menstruating and probably are not as attuned to their pelvic pain. And When we see this image, at least we can tell everyone that this is not a torsed ovary and this is an ovary that will do well.

The initial bright echogenicity of subacute hemorrhage from fibrin deposition becomes less bright and eventually fluid like as fibrin dissolves and clot lysis. One may see in such patients a reticular pattern from fibrin stands as well as a retracting clot. And these two images show no vascular flow in the material seen within the cystic area that is hemorrhage.

This is another sort of hemorrhagic ovarian s system, which a fluid debris level is seen. And occasionally when I'll see a solid appearing mass that if you look very carefully may have heterogeneous components. But this is an 18-year-old examined by transvaginal exam who had significant through transmission noted by the echogenicity beyond where the arrows are pointing to suggest that the contents was not solid within this ovary, but is actually fluid, complicated fluid in this case, this is another patient with pain, but different cause of it.

Ovarian Torsion

13-year-old with sudden pain hours ago marked off bladder. The uterus is seen here, the ovaries very large with a small amount of fluid. The ovary has peripheral cysts and this is a case of ovarian torsion.

Early diagnosis is a goal. It's rare before menarchy. It's common in the immediate post monarchial years. It results from partial or complete rotation of the ovary on its pedicle leading to first lymphatic, then venous, then arterial compromise. It is said to be more common if there's a mass in the ovary, although we see many cases without masses and a mass could be a large cyst. Fever is rare and the patient complains of sudden localized sharp pain unlike the typical appendicitis concern of periumbilical pain and then extending to right lower quadrant to McBurney's point.

Ovarian torsion ultrasound is variable due to the degree of internal hemorrhage as well as stromal edema that has occurred by the time you see the patient. So you may see an image that's cystic or an image cystic with septations or a complex one with solid and cystic structures or a solid mass, often homogeneous.

This is an example of a very severe torsion that is completely infarcted ovarian tissue. And this is just clot in a shell of an ovary. This is an ovarian torsion due to a contained mass 14-year-old awoke with sudden pain at AM inducing vomiting. This is the image I point to a geographic highly echogenic component of the mass, which was fat in a tors ovarian mass, which was a dermoid seven of 11 cases of torsion described by RAF and Itzhak. An Israeli group, in among older children or teenagers that they were studying, produced a relatively patho mnemonic image that we've shown you, which is peripheral cysts and a solid ovary.

It is said that the ovary and torsion is solid more typically in the adolescent and the rarer pediatric cases is more cystic. So again, this is an enlarged ovary with multiple peripheral cortical cysts. Evidence of ovarian torsion, here's a teen with a very large right ovary. It looks a little bit bi lobe. It measured 10.1 by 4.3 by 4.6 centimeters are greater than a DC. The typical ovarian torsion in the adolescent or adult that I see is at least three to four times normal volume. So if we consider normal volume as 15 to 20 cc, then I should be worrying at around 50 cc for abnormality. And the ovary of concern should be much larger than the other ovary.

So that image alone would've suggested ovarian torsion because of its large size, it is morphology and not doppler. That is the leading aid in analyzing ovarian torsion. But we looked, and I've pointed out in arrows, all these peripheral cysts in this kid with an ovarian torsion and the classic peripheral cyst confirmed it and surgery confirmed it.

So again, stark and Siegel in 94 said that ultrasound findings vary with age, with regard to ovarian torsion. And they said that neonatal and young children, their ovarian torsion mass is predominantly cystic or complex and often extra pelvic because the pelvis is small. Some of this may be related to the longer time it takes to make the diagnosis. Typically an adolescent who will more likely come in with a greater ease in pinpointing the area of concern, their ovary, particularly earlier in torsion who be predominantly solid.

So this is an example of a six pound 14 ounce one day old with a large cystic mass of 3.9 by 3.0 centimeters within the abdomen that at surgery proved to be a torsed ovary. This was probably a torsion in fetal life.

This is an example of another individual, very large ovary with a fluid debris level that indicated ovarian torsion, fetal neo and neonatal ovarian cysts when has to be wary of cysts that are pedunculated. Meaning if on one exam the ovary appears to be in the right lower quadrant and has an enlarged cystic area, and then in another exam it appears to be in the right upper quadrant or left lower quadrant, it might intimate peculation. And hence the fact that it's already been toed or contort on the pedicle itself.

Large ovarian cys that are not simple are of interest. It is said that if you see a retracting clot or a fluid debris level or multiple criss-crossing septations, one has to consider the fact that there might be ovarian torsion.

We live in an area which there is an attempt to not remove any more ovarian tissue than one has to. So one has to see what the general culture is of the facility that you work in. With regard to these workups, it is possible that if one sees septations and they're all in the same vector, that it may actually be multiple cysts right near each other rather than the crisscrossing septations of hemorrhage.

Again, color doppler is far less helpful in the diagnosis of ovarian torsion than it is for testicular torsion. And the fact that you can see testes side by side is a great help compared to ovary in which you have to look at it on one side, remember what it looked like and then look at it on the other side.

A key indicator that doppler should not be the central tool for the analysis of ovarian torsion comes from stock and Siegel's 1994 paper that said that color flow analysis, retrospective color flow analysis of 14 cases of surgically proven ovarian torsion showed flow absent in five of them, but in six cases there was peripheral flow and in three cases there were central flow within the ovary. And all of these were tased.

Doppler is therefore not reliable for diagnosis and surgically proven ovarian torsions have been seen that show central vascular flow.

This is an example of a tased ovary with no flow centrally. This is an example of a 17-year-old with acute pain and enlarged 58 cc right ovary with a cyst and when colored flow was placed on the ovarian tissue and could see it only peripherally at the same time. We were fortunate 'cause morphologically, we could tell this was an abnormal ovary because the right ovary looked like this and the left ovary was completely normal. It was a major difference at least three to four times. The volume of the left side was what was seen on the right side, the torse side.

So many years ago when I was a resident and I was on call, I would read someone as normal, no idea why they have pain and I would be asked by the ED physician, but is there a torsion? And I would have to go, I don't know. Nowadays is much easier. You're going to see a tourist ovary, there's a tourist ovary, it will be large, it'll be much larger than the normal ovary. And at one time I was giving this slide to our residents prior to their taking their first call stating that the ovary that has been toured is very large. There were articles that once said they were a hundred to 300 cc. I was seeing a large group between 75 and a hundred cc, but I've seen them smaller. So I now would prefer to say that I'm looking for three to four times the normal ovaries volume. And that many of my cases are probably no smaller than about 50 to 57 cc in an adolescent in a neonate in a pediatric patient who may have a one to two CC ovary, I have to worry about torsion at six to eight cc, particularly if there's such a difference between one side and the other.

Uterine Obstruction (Hematocolpos)

So here's a 14-year-old with diffuse pelvic pain, had similar pain like that the month before and the month before that. And these are the images, a longitudinal midline image. Any thoughts bl equals bladder. So arrows now point to the uterine wall, which is of normal thickness, but there's fluid within the uterus and there's fluid with debris in the vagina that's very dilated.

The typical adult pear-shaped uterus is seen on this slide and you can see that there's a central endometrial cavity echo and there is a solid appearing uterus, which looks quite different than that which I'm showing you in the test case. We obviously see that there's no central endometrial stripe and there's just fluid in the uterus and fluid in debris in the vagina. And this scattered debris again maybe hemorrhagic pro nace or infectious material. But in the case of someone who hasn't had a period yet who has monthly pain, we have to worry about hemato endometrial culvis meaning blood hemato in the mitro, the uterus and the cul post the vagina post monarchial age patients with vaginal obstruction.

The early presentation is no menses, but maybe you're not gonna know that the patient's supposed to have a menses. She this, such a patient will have intermittent or monthly abdominal pelvic pain. Later presentations include abdominal mass and some patients have difficulty with urination ion the degree of distension of the uterus is related to the degree of obstruction and the time since true menarchy hemato and he myometrial culvis have differential diagnostic considerations that includes imperforate, hymen, vaginal membranes, stenosis or atresia. Often these are associated with other congenital anomalies. While the imperforate hymen is not associated with any other anomalies, unless usually there's a cervical dysgenesis, there's diagnostic difficulty. If there's a partial obstruction with mullerian duct system anomalies in which there's obstruction of one horn of a bicornuate or obstruction of a duplicated vagina, in such cases one may have trouble making the diagnosis.

Here's another longitudinal image. Another case B equals bladder vehicles debris filled vagina, which is very dilated. There was not much dilation within the uterus. This is a transverse image of that vagina with debris. And this was a case of Hemato culvis Trans peroneal ultrasound, which I use for a number of things in ultrasound diagnosis was described by Scanlan in 1990 as useful in trans peroneal analysis for vaginal atresia. And he used transabdominal sonography to confirm vaginal obstruction and trans peroneal sonography to determine the length of the obstructive segment.

This is an example of that. This was an exam requested by my surgeon to know exactly how thick the area of obstruction was seen. So this is a perineal view in which the transducer was placed on the labia and we're able to see the dilated vagina. And we're not going deeper to see whether the uterus is involved or not, but we're able to say that there is a certain thickness marked off by the double arrow of the hymen or whatever the obstructing structure is.

Pelvic Inflammatory Disease (PID)

This is another patient with pain. Transverse view shows a uterus marked U but a multicystic, somewhat debris filled structure in a 15-year-old. And the question is any thoughts?

So one could say one has he hemorrhagic cysts physiologic cyst, but there's an added fact this person has cervical motion tenderness with cervical motion tenderness. One has to know again that one has to consider particularly in a case with fever or high white blood cell count and a sexual history, one has to consider pelvic inflammatory disease and in this case a two ovarian abscess, PID is epidemic among teens.

All three of these criteria must be present to make the call. It includes lower abdominal pain history or lower abdominal tenderness with or without rebound cervical motion tenderness. And a nexel tenderness criteria for diagnosis include one or more of the following, fever greater than 38 degrees centigrade leukocytosis greater than 10,500 WBCs per cubic millimeter and elevated ESR of greater than 20 millimeters an hour plus either a positive gram stain from the endocervix with gram-negative intracellular diplococci as in n Nigeria gonorrhea or a positive Chla Diaz test from end. The endocervix indicating chlamydia tracom is two major causes of PID ultrasound findings can be considered in stages in which involvement just of the singes, the fallopian tubes will show no abnormal ultrasound findings. The over the fallopian tubes are typically not seen on ultrasound saling, zingo oil PHUs in which there's involvement of fallopian tube and the ovaries can sometimes show enlarged a adherent to nexa.

The koala bear sign that we described many, many years ago, usually seen bilaterally once inflammation occurs and the ovary hugs the uterus were seen without major space between it and the uterus. It'll stay like that forever. And therefore you can't tell when there's a koala bear sign whether the infection is GYN or not. It could be I've had cases of appendicitis and internal hernias causing inflammation, allowing ovary to hug uterine wall. But you also can't tell if it's an old PID versus a new one unless you know it's happening clinically.

Tub ovarian abscess is mixed mass replacing ovarian tissue and it can often have a cystic tubular structure within it. The hydro soine. So this is an example of salpingo titis. One sees the ovary hugging the uterus, there's no space between it. Sometimes there's a prominent endometrial cavity that can look like the nose of a qua bear. So this would be the prominent hugging ovaries, PID, the mean nexel volumes are larger in adolescence with PID then controls. According to a very old study of ours in 1987 in that study we found 19% of adolescents with PID reported had TOAs. This was in a time when people weren't aggressively looking with pelvic ultrasound. 12 of 17 of those cases were first identified by ultrasound.

So again, pelvic inflammatory disease, you consider it ultrasound, your patient ultrasound lookalikes as we've said already, one has to know what the clinical information is. So we see this structure with debris in it could be a two ovarian abscess associated with PID, but it could also be an endometrioma if there are painful periods and or infertility or it could be a hemorrhagic cyst if associated with pelvic pain.

This is another finding that may help suggest PID in back of this gored shaped uterus is a cystic structure. That was hydro psal pinks. It would be intimated that hydro cell pinks would have no echoes and psal pinks would have contained echoes. But I've seen hydros pinks with echoes and psal pinks without contained echoes. And this is just another example of an obstructed fallopian tube in which one can see its tortuous nature.

Ovarian Teratoma

This is another patient with pain cystic area, seen an echogenic area seen it has shadowing 16-year-old a the echogenic area with shadowing was a Roku tansky nodule. The cystic area seen was a cystic component of the dermoid and one can see that the Roku tansky nodule, which has calcification in its shadows. The diagnosis again, ovarian teratoma, it's pretty classical ovarian teratoma. It's the most common ovarian neoplasm in the adolescent. And normal females, normal adult females, it's usually asymptomatic, but it's said that as up to a third can present with pain or mass. 25% are said by some to present with bilateral involvement, but I think this is overkill and it's no more than 10%. Most have a prominent cystic portion and at least one mural. Kuski nodule echogenic contents may be fat echogenic contents. That shadow may be teeth, bone, hair, and it said sebaceous material, although I don't know why sebaceous material shadows, these are two less than typical ovarian teratomas.

I point to key echogenic structures. On the left is a fat debris level, a very large ovarian mass that was removed on the right. There is an echogenic area consistent with fat within the ovary itself, not beyond the ovary. So it's an inter ovarian dermoid. And these days they do not operate on ovarian dermoids. They would only operate if it went beyond the walls of the ovary.

This is a transverse view of a uterus in which a large echogenic structure is seen to the left. Sometimes one can have air within bowel simulate this, but this is pretty sharp and also has a small cystic area within it, which suggested to us that this was an echogenic. Ovarian teratoma. They're sometimes very echogenic without a cystic component. Transvaginal exams can sometimes show individual hairs And these can simulate reticulations of hemorrhagic cyst. This is a transvaginal exam in which there are reticulations of a hemorrhagic cyst, which I think are crisscrossing and do not simulate. But there are different opinions.

Gastrointestinal Simulators of Gynecologic Pelvic Pain

Gastrointestinal disease, maybe a simulator of gynecologic pelvic pain. I show only a couple of examples. This is a 16-year-old with right pelvic pain, 21,000 WBCs. We often ask for a pelvic ultrasound in a right lower quadrant empty bladder ultrasound when someone is suspected of having appendicitis to one analyze gynecologic structures, particularly if it's a girl or analyze the pelvis if there is a low position appendix, before we go to the right lower quadrant and do an ultrasound before we even consider going to ct. Which over time and has it evolved, the concept that we're trying to decrease the amount of cts we're using to evaluate appendicitis. Ultrasound is a great tool for appendicitis. Sometimes you need a ct.

This individual had a normal pelvic ultrasound. We obtained the right lower quadrant ultrasound. It's kind of a chubby patient. Linear ray transducer shows this structure, blind ending, tubular looking structure. Thick walls greater than six millimeters, which is considered abnormal in ultrasound. And the yellow arrow points to a calcification, which sometimes can be seen in there. So it's appendicitis, a non perforated appendicitis with a contained appendicular. And this is just the color Doppler example showing some increased color flow at the tip of the appendix, which can be seen.

We showed this At some point in a key exhibit, when this was first reported and then it was later reported by Siegel and Al in the literature. So again, here's appendicitis, tubular blind ending structure greater than six millimeters with color flow in its walls. Sometimes you see highly echogenic areas at the periphery of the appendix, which is the equivalent of the increased marking seen within the fat surrounding the appendix on ct. So the echogenic area would be inflamed fat. And this is an example of what some people say they see commonly and I don't see commonly, which is a very normal appendix. So posterior to rectus abdominis is this tubular structure, nowhere near six millimeters. The blind ending that is a normal appendix.

This is a 15-year-old right pelvic pain who did not have a tubular blind ending structure but had what had very, very thick bowel wall, thick bowel wall. This white area here is just the lumen, the collapsed lumen. There's thick bladder wall. And this is an individual, whose central echogenic mosis being shown, who had a cause of thick bowel wall, thick bowel wall, which is Crohn's disease and one can see increased flow to the wall in the Crohn's disease. And the person had some free fluid.

Summary

So to sum it up, teenager with pelvic pain. Ultrasound should be used to examine and evaluate for ovary for enlargement in cases suggesting torsion or possible PID check the uterus for possible obstruction in cases of primary amin, in particular, check nearby bowel for appendicitis or Crohn's disease. Perforated appendicitis will not have a tubular blind ending structure of greater than six millimeters, but might have a collection nearby. And in cases in which there's a question of pregnancy, checking the pelvis for possible ectopic pregnancy is something to be concerned about. If there's secondary amenorrhea, the end.