Prenatal diagnosis of bladder exstrophy by 2D and 3D ultrasound

We are presenting a case in which prenatal diagnosis of bladder exstrophy was successfully performed at 23 weeks by the use of two-dimensional (2D) and three-dimensional (3D) ultrasound. The mother was 30 years old, primigravida. During a routine ultrasound scan the bladder was not visualized, the umbilical cord insertion was displaced downwards by an echogenic abdominal wall mass and 3D ultrasound confirmed an abdominal bulge below the umbilical cord insertion by the use of surface rendering mode. No other obvious fetal defect was observed. The anomaly was managed expectantly and genetic amniocentesis was not recommended. A viable female fetus was delivered at 39 weeks by elective Cesarean section with a birth-weight of 2555 g and Apgar score of 10/10. Postnatal clinical assessment confirmed the diagnosis and surgical intervention was performed 24 hours after birth for the reconstruction of the defect with a good neonatal outcome. The infant is one year old at present and in good condition. Prenatal diagnosis of bladder exstrophy is difficult and it has been extensively documented in 12 previously published cases. To our knowledge, this is the second report of prenatal diagnosis of bladder exstrophy supported by 3D ultrasound. Surface-rendering mode is a computerized algorithm which facilitates the imaging of surfaces within a region of interest in a three-dimensional fashion, rather than in cross-sectional planes. Surface rendering mode appears to be a helpful tool in the diagnosis of bladder exstrophy permitting the visualization of abdominal wall bulge, cord insertion and genitalia, playing a substantial role in the study of the anatomy. In this case 3D ultrasound was helpful in confirming the diagnosis of bladder exstrophy and simplified explanation and discussion with the parents.