Ch. 15 Fetal Genitourinary System Flashcards
The fetal kidneys can be identified as early as
12-14 weeks
The fetal urinary bladder can be seen as early as —- weeks and should be routinely seen by — weeks
10 weeks, 16 weeks
The fetal bladder should fill and empty every
20-30 minutes
T or F, we routinely visualize the fetal ureters
False. They are seen only when dilated
What size should the adrenals be in comparison to the fetal kidneys?
The adrenals should always be smaller than the kidneys
What anomaly is associated with unilateral renal agenesis?
Single umbilical artery
Bilateral renal agenesis is associated with what condition?
Potters syndrome
What does potters syndrome consist of?
Bilateral renal agenesis, pulmonary hypoplasia, characteristic facies, and limb deformities secondary to oligohydramnios
Sono finds of bilateral renal agenesis
Severe oligohydramnios (between 16-28 weeks strongly suggests renal anomalies)
“lying down” adrenal glands in the renal fossae, mimicking kidneys
absent renal arteries
Age-related renal pelvis measurements
13-20 weeks AP measurement 5mm
20-30 weeks AP measurement 8mm
30-term AP measurement 10 mm
AP Renal pelvis measurements
< or = mm Normal
5-10 mm Probably normal, follow up
> or = 10 mm 85% have anatomic anomaly
Inherited disorder characterized by symmetric renal enlargement by multiple small cysts. These cysts cause enlargement of total renal size while compressing functioning renal tissue
Autosomal recessive polycystic kidney disease (ARPKD) AKA Potters Type I
Sono finds of ARPKD or, Potters syndrome
Enlarged, echogenic, hyperechoic (due to multiple cysts)
oligohydramnios
small bladder
Renal disorder that occurs when there is obstruction of the kidney during its development which leads to the formation of cysts replacing normal renal parenchyma
Multicystic dysplastic kidney (MCDK) AKA Potters type II
Sono finds of potters type II, bilateral
Multiple, peripheral, randomly located variable sized cysts
no fetal bladder seen if renal insufficiency is present
possible oligo
How do the sono finds of Unilateral MCDK differ from bilateral MCDK?
UNI - normal contralateral kidney
the bladder will be seen in the presence of adequately functioning renal tissue ( unlike bilateral)
What is the most common cause of fetal hydronephrosis
Ureteropelvic junction obstruction (UPJ obstruction)
Sono finds of UPJ obstruction
dilated renal pelvis
thinning of the renal cortex in chronic states
NO hydroureter
Where does UPJ obstruction occur
From the renal pelvis into the ureter
What is the LEAST common cause of hydronephrosis
Ureterovesicular obstruction (UVJ obstruction)
Where does UVJ obstruction occur?
At the point where the ureters enter the bladder
With ureter duplication, often the ureter draining the upper pole will insert ectopically and will result in a
Ureterocele (herniation of the distal ureter into the bladder)
A tortuous cystic intra-abdominal “mass” in the fetal pelvis
Congenital or obstructive megaloureter
Term for dilation of a ureter
Ureterectasis
UVJ stenosis will result in varying degrees of
Hydroureter and hydronephrosis
Most bladder outlet obstructions are found in which gender?
Males
What is the most common cause of bladder outlet obstructions in male fetuses
Posterior urethral valves
What is the most common cause of bladder outlet obstructions in female fetuses?
Cloacal malformations or urethral atresia
Sono finds of posterior urethral valve obstruction (PUV)
Massive bilateral hydro and hydroureter
dilated bladder with “KEYHOLE” sign
male sex
bladder wall thickening
moderate to profound oligo \
Congenital folds of the urethra act as valves and obstruct urinary flow
Posterior urethral valve obstruction
This condition is not compatible with life as there is no amniotic fluid after 16 weeks and pulmonary hypoplasia is certain due to complete obstruction
Urethral atresia (can occur in Female and Male fetuses”
A rare and complex malformation that is essentially a convergence of the GI and genitourinary tracts. The single opening may become obstructed and result in dilatation of both GI and GU tracts
Cloacal malformations
A cystic mass that is located between the fetal anterior abdominal wall and the anterior portion of the urinary bladder
Patent urachus aka Urachal cyst
What is the most common cause of prune belly syndrome?
Posterior urethral valves
Prune belly syndrome is aka
Eagle - Barrett syndrome
What is prune belly syndrome
Weakened abdominal wall musculature in conjunction with massively dilated ureters, bladder and kidneys
Eagle-bennett syndrome is associated with —– bc of prolonged or severe oligo
Pulmonary hypoplasia
Sono finds of prune belly syndrome
abnormal compression of the abd wall by fetal small parts
oligo
bilateral hydro and a massive distended urinary bladder
The testis should descend into the scrotum at what gestation
between 26-34 weeks
T or F, all hydroceles seen in utero are reason of concern
F, small hydroceles are common in utero, large ones warrant postnatal followup
Term for when the urethra in a male fetus is not located at the tip of the penis
Hypospadias
In this condition, the urethra does not develop into a full tube, and the urine exits the body from an abnormal location.
Epispadias
Why would you seen ovarian cysts prenatally
Maternal hormone stimulation (should resolve after birth)
