P153: Prenatal sonographic findings of cloacal anomaly

Abstract

Objective: To evaluate the sonographic characteristics of the cloacal anomaly on prenatal ultrasound and to correlate with pathologic findings. Methods: From March 1991 to December 2002, eight cases with the persistent cloaca (4 cases in female 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 findings, 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 sonographic findings of the persistent cloaca were absent bladder (n = 2), distended bladder (n = 2), and small thick bladder (n = 1). Sonography of 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 sonographic 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 ligohydramnios. Conclusions: 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.