**3.8. Prune belly syndrome**

especially in cases where a wide range of disorders is associated with CE. If the couple decides to continue with the pregnancy, US assessment can help in correct planning of surgical inter-

**Bladder exstrophy** represents an AWD with a failure of the anterior bladder wall to close normally, due to the lack of muscular or connective tissue [93]. The reported incidence is 0.25–0.5 in 10,000 births, more common in males in the ratio of 2:1 [94]. The main US finding described for prenatal diagnosis is the absence or non-visualization of the bladder, as the bladder is open to the abdominal wall, and urine is released directly into the amniotic fluid. According to the American Institute of Ultrasound in Medicine guidelines, a normal bladder must be demonstrated from the first trimester as a midline fluid-filled structure flanked by the umbilical arteries in color Doppler examination [95]. Other US findings include: lower abdominal protruding mass, formed by the exstrophied bladder, lower umbilical insertion and an umbilical cord cyst and external genitalia malformation, represented by a small penis with anteriorly displaced scrotum. Also, in females, a bifid clitoris and uterine and vaginal anomalies can be identified [93], besides a widening of the iliac crests [96]. The accuracy and sensitivity of the US can be relatively low, as not all signs are always present, and an urachal cyst may mimic the presence of the bladder [97]. Bladder exstrophy should be considered if no urinary bladder is visualized, and there is no oligohydramnios associated or other renal abnormalities. Still, for the differential diagnosis with an empty bladder, the scan of the lower abdomen should be repeated in 15 minutes interval. Also, the exclusion of CE should be made, as the management is more complicated and the prognosis poorer. Prenatal US correct detection of the anomaly helps in parental counseling and recommendation for delivery in the tertiary center, as the prognosis is quite favorable. The postnatal management includes early surgical procedure to close the anterior wall defect within the first 3 days after birth. If the surgical repair is performed later, there is a higher risk of urinary incontinence or uterine prolapsed, infertility and increased risk of bladder adenocarcinoma [86]. Besides the bladder closure, pediatric surgeons must repair also the epispadias simultaneously, or in staged inter-

vention, to offer an acceptable appearance and function of the external genitalia [98].

**3.7. Omphalocele-exstrophy of bladder-imperforate anus-spinal deformities** 

The urachus is a primitive structure between the umbilical cord and the bladder, in developing fetus. It disappears normally prior to delivery, but in rare cases, parts can persist. The urachal cyst is a sinus considered a congenital urachal remnant abnormalities [99]. It is diagnosed in children, by means of ultrasound and MRI. It usually suspected if there is bleeding in the cyst or infection. The infected urachal cyst can rupture into the peritoneal cavity, leading to peritonitis. The first line treatment is the surgical procedure of complete primary excision

OIES complex represents the most severe expression of the abnormal development of the cloaca with the arrest of the urorectal septum in the 7th–8th week of gestation. The reported

**3.6. Urachal cyst**

with excellent prognosis.

**complex (OIES complex)**

vention with minimal damage to the exposed organs.

216 Congenital Anomalies - From the Embryo to the Neonate

The prune belly syndrome is another rare congenital syndrome, characterized by deficient abdominal muscles, urinary tract abnormalities and cryptorchidism in male fetuses. The pathophysiology has not been completely elucidated, as some consider the syndrome as a consequence of severe bladder outlet obstruction and others consider an abdominal muscle deficiency, secondary to a migration defect of the lateral mesoblast between weeks 6 and 7 of pregnancy [102]. The incidence is estimated to be 1 in 35,000 to 1 in 50,000 live births. The antenatal diagnosis is obtained during the second trimester scan, when megacystis is noticed, and an abnormally distended abdomen, in the absence of keyhole sign. However, there are reports in regards to the early US diagnosis [103, 104]. In the most severe form of Prune belly syndrome, a high incidence of oligohydramnios, pulmonary hypoplasia and ultimately stillbirth is reported [105]. Often, termination of pregnancy is the couple's option in early pregnancy. The postnatal management may include a single comprehensive surgical approach or a multiple step one, with good long-term results, but with a considerable incidence of iterative surgery and progression of the disease [106].
