Fetal surgery for obstructive ureterocele using an ultrasound-guided needle laser ablation technique: a case series

Obstructive ureterocele is an intravesical cystic dilation of the distal end of the ureter associated with anhidramnios and dilation of both renal pelvises.

This is a case-series of prenatally diagnosed ureterocele. Cases were selected at a third level reference hospital in Monterrey Mexico between 2010 and 2018. Eligible patients for fetal therapy were selected when bilateral hydronephrosis and severe oligohydramnios were found before 26+0 weeks of gestation. The fetal intervention comprised an ultrasound-guided needle laser technique for ureterocele ablation.

There were six cases of prenatal diagnosed of ureterocele, two cases showed anhidramnios at 23 weeks of gestation and were considered obstructive ureterocele. For these two cases, fetal surgery was performed using laser ablation of the ureterocele through an ultrasound-guided needle. In both, the urinary tract was decompressed, and the volume of amniotic fluid improved allowing to carry both pregnancies until term, one of them vaginally and the other by cesarean section. In the postnatal follow-up of both cases, the first neonate died due to neonatal asphyxia at 48-hours, and the second neonate required removal of the abnormal collecting system.

The use of ultrasound-guided laser ablation for the decompression of obstructive ureterocele is a safe and feasible technique in extremely premature fetuses that could allow survival of the affected fetus until term. Patients receiving an early prenatal diagnosis of obstructive ureterocele may benefit from fetal therapy to reduce the risk of lung hypoplasia and stillbirth.Established factsPrenatal mortality of bilateral obstructive ureterocele is up to 45%.Only a few techniques have been described for the management of prenatally bilateral obstructive ureterocele; among them, the puncturing of the ureterocele which may require more than one intervention during fetal, laser by fetoscopy which may increase the risk of postoperative complications, and ultrasound-guided laser fulguration which seems to be effective and safe.Novel insightsThe present is the first description of a case series on ureteroceles comprising two ultrasound-guided laser therapy as an effective treatment for bilateral obstructive ureterocele requiring a single intervention.The use of ultrasound-guided laser in obstructive cases avoids fatality and lung hypoplasia due to severe oligohydramnios. Still, the neonatal prognosis of the affected side at two years of age remains unchanged.