J Korean Soc Med Ultrasound.  2002 Sep;21(3):185-190.

Prenatal Ultrasonographic Findings of Cloacal Anomaly

• Song MJ

Abstract

PURPOSE: To evaluate the ultrasonographic characteristics of a rare malformation comples, Cloacal anomaly on prenatal ultrasonography.
MATERIALS AND METHODS
From March 1991 to July 2001, eight cases with the persistent cloaca (4 cases in female and 1 case in male) and cloacal exstrophy (3 cases) diagnosed by prenatal ultrasound examination were included, and all of them were pathologically confirmed by autopsy. One radiologist retrospectively analyzed the prenatal sonographic images, including the urinary bladder, kidney, pelvic cyst, abdominal wall defect and amount of amniotic fluid.
RESULTS
The ultrasonographic diagnosis was established at 21.8+/-7.8 weeks of gestation. The prenatal ultrasono-graphic findings of the persistent cloaca were absent bladder (n=2), distended bladder (n=2) and small thick bladder (n=1). Sonography of the kidney showed normal (n=2), hydronephrosis (n=1), dysplasia (n=1) and unilateral hydronephrosis with absent contralateral kidney (n=1). Four fetuses showed septated pelvic cyst; three fetuses, oligohydramnios. The prenatal ultrasonographic findings of cloacal exstrophy included absent bladder (n=3), normal kidney (n=1), hydronephrosis (n=1) and absent kidney (n=1). All fetuses with cloacal exstrophy had abdominal wall defect while two of them had oligohydramnios.
CONCLUSION
A prenatal diagnosis of persistent cloaca can be confidently made when there is septated pelvic cyst combined oligohydramnios, sediments within the cyst and intraluminal calcifications. Cloacal exstrophy should be included in diagnosis if there is a low abdominal wall defect with absent urinary bladder.

MeSH Terms

Abdominal Wall
Amniotic Fluid
Autopsy
Cloaca
Diagnosis
Female
Fetus
Humans
Hydronephrosis
Kidney
Oligohydramnios
Pregnancy
Prenatal Diagnosis
Retrospective Studies
Ultrasonography
Ultrasonography, Prenatal
Urinary Bladder