Laparoscopic Versus Mini-incision Open Dismembered Pyeloplasty for Treatment of Ureteropelvic Junction Obstruction in Children: a Comparative Randomized Trial.

Uretropelvic junction ( UPJ ) obstruction is a common congenital disorder , but not all cases require surgical intervention. Indications for surgical intervention include impaired split renal function (< 40%), a decrease of split renal function of > 10% in subsequent studies, poor drainage function after the administration of furosemide, increased anteroposterior diameter on US, and grade III and IV dilatation as defined by the Society for Fetal Urology. The open dismembered pyeloplasty was the historical gold standard repair of uretropelvic junction obstruction. Schuessler et al. introduced the first laparoscopic pyeloplasty (LP) 1993 followed by Peters et al, who performed the first pediatric laparoscopic pyeloplasty. Since then, minimally invasive pyeloplasty (MIP) -laparoscopic and robotic assisted- had an increasing interest among urologists and became widely adopted by many centers as a standard surgical intervention in UPJ obstruction; thanks to the decreased postoperative pain, short hospital stay, reduced postoperative recovery time, and comparable success rates. The high cost and long learning curve hindered generalization of MIP in all centers. On the other hand, in children many authors reported mini incision open pyeloplasty with very small subcostal muscle splitting incision, with negligible postoperative pain and very short hospital stay . Tanaka et al. have reported that the benefits of laparoscopic pyeloplasty were evident only in older children . Till now 85% of infants are still treated with open pyeloplasty . According to the EAU guidelines 2023 "There does not seem to be any clear benefit of minimally invasive procedures in a very young child but current data are insufficient to defer a cut-off age " .

Most of the studies that compared open to LP didn't limit cases to mini-incision open pyeloplasty.

To our knowledge there is no prospective randomized study comparing laparoscopic to open pyeloplasty with mini-incision in children to date.