Learning objectives
The purposes of this exhibition are to review the radiologic findings of variable conditions of fetal urinary bladder and associated anomalies.
Background
Evaluation of the fetal urinary bladder is important to detect the associated anomalies of urinary tract and other fetal organs.
Recently we have experienced many cases of urinary tract anomalies associated with normal and abnormal feature of urinary bladder.
Imaging findings OR Procedure details
1.
Normal urinary bladder of fetus (Figure 1-2.)
The fetal urinary bladder is well visualized during the 1st trimester.
In many instance,
however,
the bladder is not visualized during the US exam without definite abnormality.
Although the fetus normally fills and empties bladder every 30 to 45 minutes, urinary bladder is visualized during the US exam in the 2nd and 3rd trimester.
The bladder wall is very thin and located in the central pelvis.
Bilateral internal iliac arteries run around the bladder and branch the...
Conclusion
Early detection and differential diagnosis of variable conditions of fetal urinary bladder and associated anomalies are very important.
Megacystis during the 1st trimester usually associated with bladder outlet obstruction such as posterior urethral valve and cloacal malformation.
Invisible bladder during the 2nd trimester usually needs careful radiological evaluation of the fetus and estimation of amniotic fluid volume.
Invisible bladder with severely decreased amniotic fluid means impairment of urine production caused by bilateral renal agenesis,
bilateral MCDK,
autosomal recessive polycystic kidney,
and syndromes such as sirenomelia...
References
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Clayton DB,
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Prenatal ultrasound and urological anomalies.
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2012;59:739-56
2.
Chapman T.
Fetal genitourinary imaging.
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2012;42:S115-23.
3.
Osborne NG,
Bonilla-Musoles F,
Machado LE,
Raga F,
Bonilla F Jr,
Ruiz F,
et.
al.
Fetal megacystis: differential diagnosis.
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2011;30:833-41.
4.
Promsonthi P,
Viseshsindh W.
Case report and review: prenatal diagnosis of congenital megalourethra.
Fetal Diagn Ther.
2010;28:123-8.