Prenatal ultrasonic diagnosis of anterior abdominal wall defects.

Nine cases of different types of anterior abdominal wall defects were diagnosed prenatally by ultrasound: gastroschisis (one case), omphalocele (five cases), exstrophy of the cloaca (one case) and the extreme form of prune belly syndrome (two cases). The ultrasonic features of gastroschisis and omphalocele are well recognized by most experienced sonographists. The ultrasonic prenatal diagnosis of exstrophy of the cloaca has not been reported previously and it is a very rare entity. The anterior abdominal wall defect is larger than in omphalocene and is located infraumbilically. Fetal ascites and a lumbosacral myelomeningocele are present as well. The extreme form of prune belly syndrome is associated with the absence of the abdominal wall musculature and marked dilatation of the urinary tract, presented ultrasonically as multiple large cysts occupying the distended fetal abdominal cavity. The differential diagnosis of these entities and guidelines for their correct prenatal ultrasonic diagnosis will be discussed.