neonatal and pedatric pelvis Flashcards
how do oogonia multiply?
rapidly by mitosis
What do the primary sex cords converge to form?
a network of canals called the RETE OVARII
XY chromosome is…
male
XX chromosome is…
female
fetal gender is determined by?
sperm which fertilizes ovum
Which ducts mostly form female reproductive system??
Müllerian ducts
what forms the uterus and upper third of the vagina?
the Müllerian ducts
what do the fused caudal ends of the Müllerian ducts form?
vagina
cervix
uterus
When do the Müllerian ducts elongate?
7-12 weeks gestation
how does fusion occurs?
caudal to cranium…bottom to top
What is the wall thickness of the bladder?
Full: 1.5-3mm
empty or partially filled: <5mm
should be a smooth, thin wall
How do you varify the bladder jets?
with color doppler…ureters should not be dilated
Should you see fluid in the neck and urethra of the bladder?
no…no fluid should be visualized
Where do the ureters enter the bladder?
at the trigone of the bladder…posterior edge small indentation
What are you looking for if you see fluid in the neck or urethera of the bladder?
an obstruction
What are the specifics of a newborn uterus?
Prominent - maternal hormones
pear shaped
length 3.5cm
fundus/cervix ratio: 1:2
What are the specifics of a 2-3 month old baby’s uterus?
teardrop shape - tublular configuration
length 2.5-3cm
fundus/cervix ratio: 1:1
no discernible endometrial stripe
What does the uterus of a child age 7 look like?
begins to increase in size and take on the pear shape
what does the pubtery/ post pubery uterus look like?
dramatic changes in shape and size
length 5-7 cm
fundus/cervix ratio 3:1
What does the vagina look like in children?
difficult to properly evaluate
full bladder need to scan
tubular structure posterior to bladder
continuity with cervix
bright central echo
Where do you find pediatric ovaries and what size are they?
use volume measurement
may be difficult to see- anywhere between lower pole kidneys to true pelvis
size stable up to 5 y/o 0.75 - 0.86 cm cubed
Why would a newborn have prominent follicles in the ovary?
because of maternal hormones
What causes congenital anomalies of the uterus and ovaries?
developmental abnormalities
interference with blood supply or distortion of uterine cavity
may cause infertility or spontaneous abortion
What percentage of females have congenital anomalies of the uterus and ovaries?
approx 0.5%
If you have a renal abnormality what else do you probably have??
a congenital uterine or ovarian abnormality
If you find a Müllerian anomaly what should you ALWAYS check??
the kidneys
How are mullerian anomalies classified?
into six groups based on prognosis for future fertility and surgical correction
What is class 1 mullerian anomalies?
incomplete vaginal canalization
what is class 2 mullerian anomalies?
unicornuate uterus
what is a class 3 mullerian anomaly?
uterus didelphys
what is class 4 Müllerian anomaly?
bicornuate uterus
What are the details of a class 1 mullerian abnormality?
segmental mullerian agenesis (incomplete vaginal canalization)
vaginal atresia
What is a hydrocolpus?
fluid filled vagina
what is a hydrometrocolpos?
fluid filled vagina and uterus
what is a hematometrocolpos?
blood filled vagina and uterus
what are the signs of vaginal atresia?
hydrocolpus
hydrometrocolpos
hematometrocolpos
cervix may be absent
large cystic pelvic mass in neonatal period or dx at puberty
imperforate hymen
What are the details of a class II Müllerian anamoly?
unicornuate uterus
complete unilateral arrest of Müllerian ducts
may have small rudimentary horn if partial arrest
long, slender uterus (cigar shaped)
deviated to one side
frequently renal agenesis on contralateral side
small laterally positioned uterus
infertility and pregnancy loss
What are the details of a class III Müllerian ducts anamoly?
uterus didelphys
complete nonfusion of the Müllerian ducts
complete duplication of uterus cervix and vagina
not usually associated with infertility problems - no treatment
The fundus of each is completely separate
2 endometrial echo complexes
What is a class IV Müllerian duct anaomly?
bicornuate uterus
partial non-fusion of the Müllerian ducts
duplication of the uterus - common cervix
wide spaced cavities
low incident of fertility complications (not usually treatment)
rudimentary cavity = 12-16 weeks gestation, uterine cavity rupture
2 endometrial cavities visualized
What is a class V mullerian anamoly?
Septate uterus
HIGHEST INCIDENCE of infertility problems
MOST COMMON UTERINE ANOMALY
What is a class VI Müllerian duct anamoly?
exposure to diethylstilbestrol (DES) in utero-synthetic drug used in the 1970’s during pregnancy to treat threatened and habitual abortion (miscarriage)
drug causes vaginal malignancies in their daughters
uterus: normal shape and size
uterine cavity: “t” shaped, irregular contour
What is ambiguous genitalia?
two types:
hermaphroditism
female pseudohermaphroties
What is true hermaphroditism?
both ovarian and testicular tissue
internal and external genitalia variable
46 XX daryotype or mosaics (46XX/46XY)
What is female pseudohermaphroties?
46, XX karyotype
no duplication of internal structures just external structures
increase production of androgens or androgen therapy for mother
masculinization of external genitalia (enlarged clitoris, abnormalities of urogenital sinus and partial fusion of the labia majora)
ultrasound used to determine presence or absence of uterus, vagina and ovaries
Why is ultrasound used for ambiguous genitalia?
to determine presence or absence of uterus, vagina, and ovaries
What are the two types of precocious puberty?
True precocious puberty
precocious pseudopuberty
What is True precocious puberty?
ALWAYS isosexual (same sex…girl with girl parts, boy with boy stuff)
development of secondary sexual characteristics and increasing size and activity of reproductive organs prior to normal puberty age usually < 10y/o
uterus enlarged, postpubertal configuration 2:1 and 3:1 fundus/cervix ratio
ovarian volume enlarged > 1 cubic cm functional cysts present
What is precocious pseudopuberty?
Maturation of secondary sexual characteristics but not reproductive organs (boys can develop breasts, girls facial hair)
no activation of hypothalamic -pituiitary-gonadal axis
usually associated with increase steroidal release from adrenal glands = tumors
should always scan the liver and adrenal glands to rule out lesions
Why do we ultrasound precocious puberty?
to scan the liver and adrenal glands to rule out lesions or tumors that will create increase in steroid release
What is a pediatric ovarian cyst?
ovarian cyst…may form in utero but spontaneously resolve
3-7mm cysts normal
higher incident in neonates fo mothers with toxemia, diabetes, RH isoimmunization - greater than normal release of placental chorionic gonadotropin
What is the criteria to call something a cyst?
round or oval
well circumscribed
smooth thin walls
posterior enhancement
anechoic
What is a torsion?
when there is sudden onset of severe pain and no blood flow is reaching the testicle or ovary…no blood flow, color or power doppler registers
What is ovarian torsion
may occur at any age
sudden onset of severe pain
more common associated with ovarian cyst/mass
arterial AND venous blood flow must be seen
venous flow will be compromised first
enlarged and edematous ovary
What does color flow show?
ONLY direction of flow not if it artery or venous so either could be blue or red
Do ovaries with torsion have color blood flow in them?
no…might have color around it, but not IN it
What are ovarian teratomas?
uncommon in adolescent and neonate
60% germ cell
benign or malignant
most common in pediatrics is benign mature teratoma or dermoid cyst….finish
What are secondary sex cords or cortical cords made from?
surface epithelium
What is a primordial follicle?
when cortical cords break up into isolated cell clusters
at 16 weeks gestation
At 16 weeks gestation what do the primordial follicles contain?
an oogonium
before birth what to all oogonia enlarge to form?
oocytes
which remain in an arrested state until puberty
What do male/female reproductive organs develop from?
same source - gonadal ridges
grow to form primary sex cords
What is fully formed by the 12th week of gestation?
external genitalia
What forms most of the male reproductive system?
wolffian ducts
What do the unfused cranial ends of the Müllerian ducts form?
Fallopian tubes
When can fusion anomalies of the Müllerian ducts occur?
throughout the process of the ducts transforming into the reproductive system
How do you image an infant/toddler pediatric pelvis?
fill the bladder
have parent keep child well hydrated
How do you image a pediatric pelvis of a potty train child?
drink 2 glasses of fluids 1 hour prior to exam
hold bladder
how do you image a young teen pelvis?
3-4 glasses of fluid 1 hour prior to exam
Do we perform endovaginal exams on children/minors?
No, unless there are extenuating circumstances
What will help you determine if you have found a cyst or if its just the bladder?
post void bladder scan will reveal if it’s a cyst or the bladder
What is the appearance of a neonatal ovary?
heterogeneous secondary to tiny cysts
what is the appearance of pediatric ovaries as they increase in age from neonatal?
homogeneous
possible small cysts
What is an a Müllerian abnormality?
improper fusion
incomplete development on one side
incomplete vaginal canalization
what is a class 5 mullerian anomaly?
Septate uterus
What is a class 6 Müllerian anomaly?
diethylstibestrol (DES) exposure
“T” shaped uterus
What are the symptoms of vaginal atresia?
symptoms: abdominal pain and distention lack of menses in pubescent child
when do you suspect class 1 Müllerian anomaly?
suspected when a girl reaches puberty without menstruaton
possible transverse vaginal septum or vaginal atresia (not fully formed)
What is a septate uterus?
2 uterine cavities - closely spaced
1 fundus
possibly 2 cervical canals or vaginal septum
How does pediatric ovarian cyst look on US?
anechoic structure adjacent to or within ovary may have debris if hemorrhage -
little or no color flow to ovary if torsion
What are the most common complications of a pediatric ovarian cyst?
hemmorrhage, torsion
may rupture
What are the malignant ovarian teratomas?
dysgerminoma
embryonal carcinoma
endodermal sinus tumor
immature teratoma
chorocarcinoma
mixed tumor
how do benign teratoma or dermoid cysts present in peds?
usually asymptomatic until it gets very large
most frequent complication is torsion 16-40%
What is the sonographic appearance of a dermoid/ teratoma?
varied -complex, heterogeneous mass
frequently echogenic foci with acoustic shadowing-
less shadowing in neonates
“tip of the iceberg” on US means DERMOID (usually much larger than what you can see)
