Pediatric Genitourinary Sonography - HD

Introduction

Hello, my name is Harriet Paul Thiel
and I practice at Boston Children's
Hospital in the United States.
My lecture today will be on pediatric GU imaging.
What I'd like to do with you is
to review four important categories
of pediatric GU disorders
where ultrasound plays a critical role in both
diagnosis and treatment.
And these four categories include congenital hydro necrosis, vesco,
ureteral reflux disorders of sex development and tumors.
And I will be discussing the off-label use
of ultrasound contrast material.

Congenital Hydronephrosis

Congenital hydronephrosis is dilation
of the renal collecting system,
and it's almost always detected on fetal sonography.
Infants are referred for evaluation after birth,
and congenital hydro necrosis may be caused
by obstruction reflux
or it may be a physiological variation without obstruction.
With ultrasound, we can determine renal length
and compare the involved side to the normal side.
We can assess renal parenchymal thickness
and echogenicity the degree of pelvic HELOC seal
and ureteral dilation, as well
as bladder wall thickness and volume.
In many instances, the patients will go on
to have avoiding cysto urethrogram for a,
an additional assessment of the,
lower urinary tract, including the bladder and the urethra,
and also to determine whether
or not there is vesco ureteral reflux.
And in a smaller number of cases,
the patients will also have a functional renal assessment
with nuclear scintigraphy, which is done,
as a MAG three study with furosemide.

We see on the sagittal
and transverse images of the kidney that there is
significant dilation of the major
and minor CAEs as well as the renal pelvis.
And there's thinning of the renal parenchyma.
There's no dilation of the ureters
and the bladder looks completely normal.
This is a single image from A-V-C-U-G
that shows a normal bladder, and there was no reflux.

Here we have images from a MAG three study,
with the upper panel done prior to the administration
of Furosemide,
and we can see that there's a, very,
distended,
kidney, with a delay in,
radiopharmaceutical uptake
and, a delay in excretion,
following the administration of Furosemide, which
is shown in the lower panel.

This is a case of ureteral vesicle junction obstruction.
We have sagittal images of the left kidney
and left flank, which show,
marked dilation
of the renal collecting system
and a very dilated tortuous left ureter.
The lower image here shows a transverse view of the bladder
with a dilated distal left ureter.
And the mag three study,
shown here on the bottom right panel, demonstrates,
delayed excretion, of the radiopharmaceutical,
into, into the, ureter
and a very dilated,
tortuous ureter seen all the way down to the bladder.

This is a young boy, a baby
with posterior urethral valves.
We can see that the left
and right kidneys both show marked dilation of the
collecting systems.
And, here we have a transverse image
of the very markedly thickened bladder
with dilated tortuous distal ureters.
On the right here we have a sagittal view of the bladder,
which again shows marked thickening of the bladder wall
with an intraluminal catheter in place.

These are images of the voiding cysto urethrogram,
which show the markedly elongated
and distended posterior urethra, the
posterior urethral valve at this level,
and then the change in caliber of the,
urethra distal to the valve.
There's a very abnormal appearance of the bladder,
which is very trabecula.
There are diverticula
and there's also extensive reflux into the left renal
collecting system and ureter.

This patient also had a contrast enhanced voiding U
sonogram, and the yellow arrow is pointing
to the level of the valve.
This, image was obtained as the patient was voiding.
We have the bladder and the urethra,
and you can see on this post void,
postoperative study rather, that the
urethra now has a, a wider caliber
and the arrows again pointing to the region
of valve ablation.
There's still a little bit of irregularity, in
that region, but the overall caliber
of the urethra significantly improved.

It's important to recognize
that there is currently a very significant variation in the
way patients with con congenital hydronephrosis are managed,
and this is due to a lack of evidence-based information
that correlates the severity of prenatal
collecting system dilation
to postnatal urologic abnormalities.
And in an effort to address this problem,
there was a consensus meeting held in 2014
that drew together representatives from eight different
medical societies in the United States that
were concerned in one way or another with the pre and
or postnatal diagnosis
and management of urinary tract dilation.
And the results of this consensus meeting,
were published in a report by,
heap Wind et al, published in the Journal
of Pediatric Urology in 2014, which is referenced here.

This classification is based on
six ultrasound features that include the
inter posterior renal pelvic diameter, the, presence
of CAE dilation with a distinction made between central
and peripheral CAE dilation, postnatally,
renal parenchymal thickness
and appearance, as well as ureteral
and bladder abnormalities for prenatal studies.
A seventh ultrasound feature is the quantity
of amniotic fluid.

The these two diagrams appear in the publication,
and I'm not going to go over them in detail,
but I did wanna point out that there is,
a classification for prenatal hydro necrosis
and then a separate postnatal classification.
And the patients
and their ultrasound findings are stratified into lower
and higher risk categories.
As you can see, The hope is
that future research will lead to a refinement of,
the UTD classification system that can be correlated
with other clinical outcomes such as renal function
and the need for surgical intervention.

Vesicoureteral Reflux

I'd like to move on now to a discussion
of vesco ureteral reflux, which is one
of the most common pediatric urologic abnormalities
with a prevalence estimated at about 1% of the population.
It's a common cause of prenatal hydro necrosis
and can be identified in between 30
and 50% of all children, boys
and girls who present with a first urinary tract infection.
It's also identified in approximately 27% of siblings
of patients with documented reflux
fluoroscopic voiding,
cysto otography is the reference standard
technique for diagnosis.
However, in recent years,
contrast enhanced voiding euros sonography, which is a,
an ionizing radiation free technique,
has become a viable alternative to fluoroscopic VCUG
and is in u and is in use in several centers throughout the
world, including at our, hospital in Boston
and is used in the diagnosis
and management of Vesco ureteral reflux.
And there have been many studies that have shown
that this technique has comparable
or greater sensitivity than conventional VCUG
or radionuclide cystography in the diagnosis of reflux.
And many of these studies, have been nicely summarized
in a publication by Casa Dge,
that appeared in pediatric radiology in 2010.

This technique is performed
after bladder catheterization,
which is done the same way we would do for it,
for conventional, fluoroscopic study
and the intravesical infusion of normal saline
that contains the ultrasound contrast agent
and we then perform sequential imaging of the bladder,
the kidneys, and the urethra during bladder filling
and during voiding.
And the severity of the reflux can be graded with a scale
that is similar to the five,
category international grading system that is used
for conventional voiding, cysto urography
and higher grades of reflux are associated
with reduced renal parenchymal function.

Here's an example of a three month old boy who was referred
after a prenatal diagnosis of hydronephrosis.
We see here sagittal images of the right
and left kidneys that show mild dilation
of the renal pelvis bilaterally, a normal appearance
of the urinary bladder
and a normal voiding cysto urethrogram without evidence
of reflux on either side.
The patient underwent a contrast,
enhanced voiding s sonogram at the same sitting.
And I'd like to show some of this patient's images to you.

Here we have a clip of the bladder
with the contrast material entering the bladder,
and you'll see that the density
of the contrast material increases.
You really don't need to use much contrast material.
It, the amount will vary with the type of,
contrast
that is used, but it tends to be very small amount.
And here in the middle panel, we can see the bladder
image in the sagittal plane, on the right
and you'll start to see the ureter here filling
with the contrast material
and extending up into the right flank
and into the collecting system of the right kidney.
You'll notice that the parenchyma of the right kidney is
otherwise dark.
We do the studies, with harmonic imaging
so it suppresses the tissue, signals,
but we do, image the contrast material.
So this patient had a reflux on this right side,
and I am not gonna show you the left side,
but a similar, phenomenon was seen on the left
with reflux on the left side as well.
And here on the right we have
transperineal images obtained at the time of voiding.
So we have the bladder and you can readily see
that the urethra is normal
and we're seeing it as, as the child voids.
These are just some still frames from the study.
So, reflux into the right
collecting renal collecting system into the left renal
collecting system, a dark renal parenchyma otherwise,
and a normal appearance of the bladder
and urethra Intrarenal
reflux of infected urine is believed
to play an important role in the pathogenesis
of reflux associated poly neph or nephritis
and subsequent parenchymal scarring.
And it's traditionally been depicted by fluoroscopic VCUG,
however, we have shown,
that contrast enhanced voiding u sonography does
demonstrate intrarenal reflux
and compares favorably to fluoroscopic VCUG.
And we recently published a small case series,
from our hospital in the Journal of Ultrasound in Medicine.
And I'd like to show you, one case from that series.

This was was an eight month old girl who had pyelonephritis
and this is a sagittal view of her left kidney.
Here's spleen. You'll notice
that the upper pole parenchyma is echogenic in comparison
to the lower pole parenchyma,
and here are images from her
contrast enhanced voiding u sonogram.
We have a reference gray scale image on the left
and you can see that there's very extensive reflux into
the left ureter and the very dilated collecting system.
But I also would like you to focus on the renal parenchyma
and you can see these little dots
and lines of, of contrast
that are entering into the renal parenchyma diffusely.
And this is intrarenal reflux.
And here are a couple of still frames from that study.
We see the tortuous ureter, the very dilated renal pelvis
and CAEs, and then the,
echogenic appearance of the parenchyma due to the presence
of intrarenal reflux.
And this finding was confirmed
on the conventional voiding cysto urethrogram.
We can see that there's a big blush of con of
contrast within the left renal parenchyma.

We can also monitor, the result of endoscopic treatment
of reflux by directly imaging the bulking agents.
We can, see the, implants in a subter,
location and these implants may undergo changes in size
and shape over time.
They can also calcify
and we have shown in a couple of publications
that non visualization of the implant
or multi lobe contour on ultrasound examination,
is associated with persistent vesco ureteral reflux.
And here are a couple of images from, the time
of cystoscopy.
This is prior to
and following, injection of the bulking agent.
You can see that the ureteral orifice is very,
gaping prior to injection
and then following injection, there's quite a marked,
change in the appearance, of the sub ureteric,
region with the ureteral orifice appearing as a tiny
hole at the summit of this um, mound.
And here, is a transverse image of the bladder,
with the white arrows pointing to the,
sub ureteric mounds that we see in the region
of the bladder trigone.
Here is, another patient.
We have a transverse
and sagittal, image showing a bi lobed,
mound,
which may be associated with reflux,
and then a single mound on the left.
And here's a different patient who has a calcified um, mound
with distal shadowing.

Disorders of Sex Development

Let's move on now to a very different topic.
The topic of disorders of sex development.
These are congenital conditions with atypical development of
chromosomal gonadal or anatomic sex.
The birth of a child
with ambiguous genitalia is fortunately rare,
however, there is a substantial risk of psychological damage
to the patient and their family if the diagnosis is
incorrect or delayed.
And any deviation from a normal appearance
of the genitalia such as clin, mely
or labial fusion requires immediate evaluation.
These disorders are classified into three broad groups.
There are the sex chromosome disorders
where the karyotype is not the usual 46 XX
or 46 xy.
And then there is the group where
the children are chromosomally female
and the group where the children are chromosomally male.
And in order to adequately characterize these disorders,
there is a need for karyotyping hormonal analysis
and imaging, Which is where we fit in.
So with ultrasound, we can locate the goads,
determine whether or not a uterus is present and to,
and we can evaluate the adrenal glands
for diffuse enlargement or masses.
These patients will all eventually require gent,
which is injection of contrast material through
whatever your genital orifice is present
or avoiding cysto otography.
And this study is done to characterize the anatomy
of the urethra, the vagina, if there is one,
present the urogenital sinus and or cervix,
and also to delineate the connections of the genital urinary
and gastrointestinal tracts
to the cloaca when there is a cleal anomaly.

Sex Chromosome Disorders

Turner syndrome is the most frequent sex chromosome disorder
of sex development and in this syndrome there is an absence
of all or part of one of the X chromosomes.
The patients present with short stature, low set ears,
a we neck and a broad chest.
They will have gonadal dysfunction with amenorrhea
and sterility, a juvenile uterus
and the ovaries may not be detected
and there are a number of associated conditions
that include Hashimoto thyroiditis,
congenital heart disease, renal anomalies,
skeletal abnormalities and diabetes.

Here we have a photograph of a young girl
with Turner syndrome.
These images are of a 14-year-old girl with Turner Syndrome
and on this sagittal view of the pelvis, we can see
that she has a very juvenile appearance of her u
of her uterus with a relatively prominent cervix
and a tiny fundus.
The right and left ovaries are also very tiny

mixed gonadal genesis, which consists
of 45 x
and 46 XY mosaicism is a rare disorder
with phenotypic heterogeneity as a result
of different distributions of the chromosomal cell lines.
So some of these patients will appear phenotypically
as comp normal males.
Others, will have ambiguous genitalia including hypos,
staus, and cryptoids.
Others are phenotypically normal females with
or without short stature,
and others present as Turner syndrome
and may phenotypically indistinguishable from patients
with 45 x.
They will have a single undescended testis
and a contralateral streak.
Gonad here is,
one such child
and these photographs were lent to me
by my colleague David Diamond,
a urologist at Boston Children's Hospital.
We can see that there's a bifid scrotum
with a PHUs,
but the urethra does not, terminate at the tip
of the PHUs but actually terminates,
at the base of the scrotum.
And this patient has, hypos staus.
In the right groin there is, a testicle,
and in the left groin there is a hemi uterus
and these are images from the patient's VCUG.
When the patient voided, there was filling
of a large utricle, which is a Malian remnant,
and there is a tubular structure,
extending from the dome of the utricle
and into the left groin and it's faint,
but there's actually contrast filling, the left groin,
and this was a fallopian tube that was patent was spillage
of contrast into the,
inguinal canal and its surgery.
The patient did have a rudimentary, left sided ovary.

46 XX Disorders

Patients with 46 xx
are usually have congenital adrenal hyperplasia
with enlarged adrenal glands
and masculinization of the lower urogenital tract.
They will have a normal uterus and ovaries,
but they frequently have reflux of urine into the vagina
and uterus that may result in hydrometric culpo.

Here is one such patient with fusion
of labia and a fallous.
A sagittal sonogram of the pelvis shows the bladder
and a very distended fluid-filled vagina as well
as a fluid-filled uterus.
And here we have images of the right
and left adrenal glands, which are markedly enlarged
and cerebral form In appearance.

These are images from the patient's
avoiding cysto urethrogram.
We have a catheter coiled in the bladder,
and as the patient voids, there is filling of the vagina
and we see the impression of the,
uterine cervix on the dome of the vagina
and the,
vaginas connected with the urethra to form a
distal common channel.
The urogenital sinus,

Another much rarer.
46 xx
disorder is the so-called claco malformation.
Cica means sewer in Latin
and in these patients there is an interruption
of the normal differentiation of the genital urinary
and GI tracts.
This just, this malformation occurs only in females
and it's very rare, an incidence of one in 40
to 50,000 newborns.
There is an incomplete separation of these three tracts,
with a common confluence and a single perineal opening.
There is also an associated failure of malaria
and duct fusion and there is duplication of the uterus
and proximal vagina.
There is a persistent urogenital sinus
with an abnormal lower vagina and hymen,
and all of these patients will require colostomy at birth in
order to decompress the gastrointestinal tract.

Here are a couple of diagrams illustrating.
An example of a patient with a low confluence
of the cloacal,
a low confluence malformation.
You can see that the three tracks come together
below the level of the pubic pubic bones.
And here, on the right is a high confluence,
above the level of the pubic bones.

These are images, again loaned to me
by my colleague David Diamond from Boston
of three different patients where you can see,
there's a single perineal opening,
but they're all slightly different in appearance.
Ultrasound again,
plays an important role in sorting out, the patient's.
Anatomy. This is a sagittal view of the pelvis.
B is for bladder.
We have duplicated vaginas and a, rectum.
And this clip shows the communication
between the, two vaginas
with fluid passing between them.
The patient subsequently,
underwent a fluoroscopic examination,
and here on the left we see that there's a colostomy,
with a, an inflated balloon
and contrast has been injected through the colostomy.
It fills the rectum, which joins,
with the duplicated vaginas in between them
with opacification of the, of the two vaginas.
We also see that there's contrast
material within the bladder.
And here on the right when the patient voids,
we see the urethra
and there is, a connection between the urethra
and a single common channel,
emanating from the duplicated vaginas.
And those join up to form a single common channel,
the urogenital sinus.
And here again, we see the rectum, draining,
into the vaginas.

46 XY Disorders

46 XY disorders of sex development are disorders
of testicular development, from the primitive gonad
or abnormalities related
to substances secreted by the testicle.
And these patients will have ambiguous
or female external genitalia
that result from incomplete intrauterine masculinization.
There will be a presence or an absence of malaria structures
and patients who have normal female external genitalia will
usually seek medical attention at puberty due to the absence
of breast development and
or primary a amenorrhea, Almost all
of these patients will be infertile
and there is a risk for the development of germ cell tumors
in between 20 and 30% of patients.
And, these children may undergo surgery for female
or male social sex assignment.

Here is, some imaging of a 12-year-old genetic
male who was a phenotypic female,
who developed a glast blas stoma.
And we can see on this sagittal image
that there's a normal appearing uterus
and the patient has a right ovary
that has a somewhat unusual, appearance.
It's small, it's echogenic it.
The left ovary is abnormal as well
and has this small, echogenic mass within it,
which proved to be a Blas stoma.
We see a little distal shadowing here from the tumor.

Tumors of the Genital Urinary Tract

I'd like to move on now to a different topic.
Tumors of the genital urinary tract,
including uh, tumors of the kidney wilms tumor
and meso blast nephroma rhabdomyosarcoma
of the lower genital urinary tract, teratoma of the ovary
and epidermoid cyst germ cell
and stromal tumors of the testicle
Woman's tumor is the most common intraabdominal malignant
tumor of childhood with 80% of patients presenting
between one and five years of age.
This tumor usually grows within the renal parenchyma
with distortion and displacement of the collecting system
and capsule and is bilateral in five to 10% of patients.
Ultrasound screening is recommended
for children at high risk
and that includes those with hemi hypertrophy, sporadic
and AIA Beckwith Wheatman syndrome,
the Wagar syndrome which consists of worm's, tumor andia,
genital urinary abnormalities,
and mental retardation, neph, neuroblastoma ptosis,
and the Dera syndrome, which consists
of gonadal, dysgenesis nephropathy and wilms tumor.

Here's a patient with a Wilms tumor
arising from the right kidney.
We have sagittal view of the liver.
This is the normal right renal parenchyma
and then a very large,
somewhat more echogenic tumor arising from its anterior
aspect on this transverse view of the kidney.
We can see that there's a thrombus of the right renal vein
that's extending into the vena cava.
This is a sagittal view of the vena cava with a large,
thrombus within it, which is non-obstructive.
When this, patient was imaged with color doppler And,
here is an image a CAT scan obtained,
that showed the very large tumor
with the thrombus in the renal vein
and extending into the vena cava.
There's also ascites.

As you can see, meso
nephroma is the most common neonatal renal neoplasm
and is sometimes detected in utero.
It's a benign tumor, but may spread through local invasion
and is treated with simple nephrectomy.

Here's an example of a meso blast nephroma.
We have a very large complex mass,
with a large central zone of necrosis,
and we can see that there's significant dilation of the caly
of the involved kidney.
And interestingly,
this patient also has medullary nephrocalcinosis
with epigenic renal pyramids.
Here's a transverse view of the mass
and we can see with color doppler that it's
relatively avascular.
There's a little bit of blood flow at the periphery.
Here is the corresponding CT scan image taken.
An image in the coronal plane that shows the large mass,
the central necrosis
and the dilated upper pole CAEs

rhabdomyosarcoma, can occur in the lower urinary tract
where it's known as sarcoma Brees.
In males, it arises from the bladder base
and presents with bladder outlet obstruction.
In girls it may occur in the uterus or the vagina.

This is an 18 month old boy
with rhabdo sarcoma arising from the bladder base.
We can see it here on the sagittal view.
It has a lobulated uh, contour
and, some blood flow.
One study with color doppler.

This is a 16 month old girl
with rhabdomyosarcoma of the vagina.
This is a sagittal view.
We have the bladder, the vagina is
distended by the tumor.
Here is the uterus.
And again, a little bit of blood flow with color doppler.
This is a sagittal T one fat suppressed image obtained
after gadolinium administration
where we can again appreciate the very large mass
distending the vagina.
And here is the uterus behind the bladder.

Ovarian Teratoma

Ovarian teratoma usually occurs in the
second decade of life.
It is composed of elements of all three germ cell layers.
90% of these tumors are mature and cystic
and they're often called dermoid cysts.
The electrodermal components predominate,
they're usually unilateral,
although about 10 to 20% may be bilateral,
and they're generally five to 10 centimeters in diameter.
The ultrasound appearance of
teratoma depends on the relative amounts of sebum,
serous fluid, calcium, hair, and fat within the lesion.
And they usually contain a fewer than 50% soft tissue
elements by volume.

Here are sagittal
and transverse images of a mature ovarian teratoma.
You can see that there's cystic
and solid echogenic components.
There's some shadowing here probably due to
either the presence of hair or some calcification.

About 10% of these tumors are immature or malignant
and contain embryonic neural elements.
They usually occur in post monarchial girls
and present as an asymptomatic pelvic or abdominal mass.
They're typically greater than 10 centimeters in diameter at
diagnosis and contain more than 50%
soft tissue elements by volume.
And these tumors will meta, will
or may metastasize to, lymph nodes and liver.

Here's one such example.
We see the cystic component,
but in addition, a very prominent soft tissue,
a heterogeneous component,
and here is an image of this tumor.
On a CT scan,

Testicular Tumors

Testicular epidermoid cysts are benign,
masses painless.
They consist of a cyst that's lined with squamous epithelium
and filled with keratin,
and they may have a variety of sonographic appearances.
They're usually well-defined.
They may appear as a hypoechoic mass with world
or laminated, features
or an echogenic capsule that contains calcification
or they may be very non-specific and resemble a teratoma
and testicular sparing enucleation
is the treatment of choice.

Here's one such tumor.
And you can see that it has a varied appearance
in one region.
It kind of resembles, a teratoma with some cystic
and solid echogenic regions.
Here it's got more of an onion skin appearance
and it's, not vascular,
although it is displacing vessels on this
power Doppler image.

Between 70 and 90% of primary testicular neoplasms are
of germ cell origin with yolk sac carcinoma
and mature teratoma being the most common,
they generally present as a painless scrotal
or testicular enlargement.
There may be a hydros eal in about 15 to 20% of patients.
Yolk sac tumor generally occurs in prepubescent boys
with a median age of two years.
Teratoma usually occurs in children less than four years
of age, and about 85% of them will be well differentiated.
These, tumors follow a benign course in the pre-pubertal
population, even when the histology is immature
and tissue sparing surgery is often possible.
They tend to have a more aggressive course in
pubertal patients.
And malignant histology is more common in
orchiectomy as necessary.
Seminoma is rare in children unlike,
the situation in adults, but may occur in cry.
Testes. Malignant tumors are hyperemic
with cystic areas related to hemorrhage,
necrosis and calcification.
Teratomas contain hypo coic fluid,
echogenic calcification and fat.

Here is an example of a six month old boy
with a yolk sac carcinoma.
It's predominantly solid, well circumscribed,
although it does have small, cystic areas within it,
which may be due to necrosis
and it's fairly vascular with color doppler.

Here's a 15-year-old boy with a mature testicular teratoma.
As with the ovarian tumors, it has a varied,
appearance, echogenic, areas,
more cystic areas, and shadowing.
And, here's an image clip that just goes
through the entire tumor
and shows, the varied appearance, of the mess.

Testicular stromal tumors comprise about 10%
of the pediatric testicular neoplasms.
Cli cell tumors about 40%.
Juvenile granulosis cell tumor, another 40%,
and unli cell tumors about 20%.
Most are benign and they're generally
small and hypervascular.
Their imaging features are nonspecific
c cell tumors present in the first year of life
and they may produce estrogen, which leads to gynecomastia.
Malignant tumors are reported in older children.
The juvenile granulosis cell tumor presents in the
first six months of life.
And these are hormonally inactive
lidic cell tumors present in pre pubertal boys
with a median age of seven years,
and about 30%
of them will produce testosterone resulting in
precocious visualization.
Benign tumors are treated with enucleation
or tissue sparing surgery,
where whereas malignant tumors are treated with orchiectomy.

And here's an example of a 7-year-old boy
with precocious puberty and alytic cell tumor.
We see the well circumscribed tumor, of the testicle.
There's also some underlying,
microcalcifications within this tumor.
It's very vascular with power and color doppler,
and we have a spectral,
spectral waveforms here showing some what look like,
very low resistance, arteries
and some, venous flow as well.

Summary

In summary, I have reviewed with you four categories
of pediatric genital urinary disorders,
where ultrasound evaluation plays a pivotal role in
diagnosis and management,
including congenital hydro necrosis, sico, ureteral reflux
disorders of sex development and tumors.
Thank you.