INUTERO ULTRASONOGRAPHY - IMPACT ON UROLOGY

Prenatal detection has allowed prompt postnatal recognition and management of hydronephrotic conditions while they are asymptomatic and has substantially improved our understanding of the natural history of several urologic disorders. In children with ureteropelvic junction (UPJ) obstruction, previously, 80% were symptomatic, with infection, hematuria, abdominal/flank pain, abdominal mass, or failure to thrive, whereas currently, as many as 70% of children undergoing pyeloplasty had prenatal detection of the anomaly. In addition, it has become apparent that many infants with an anomalous UPJ or UPJ obstruction demonstrate stabilization or gradual improvement in hydronephrosis. Recognition of the vagaries of the diuretic renogram has led to the development of the "well-tempered renogram," a standardized diuretic study using MAG-3. In many infants with primary obstructive megaureter, the hydronephrotic kidney has near-normal function, and only a minority require repair. One of the more common causes of prenatal hydronephrosis is vesicoureteral reflux. Early DMSA studies in these patients has suggested that sterile reflux may have an adverse effect on renal development. In the newborn with posterior urethral valves, prenatal detection has allowed early urinary tract decompression before infection occurs. It has also become apparent that most multicystic kidneys are not palpably enlarged at birth and that the majority of the cystic lesions regress, leaving only the stromal component. Many adults thought to have unilateral renal agenesis probably were born with a multicystic