Bypass pyeloplasty: description of a procedure and initial results

Dismembered pyeloplasty is the surgical technique of choice for open, laparoscopic and/or robot-assisted repair of ureteropelvic junction obstruction (UPJO). We describe a new technique, bypass pyeloplasty, ideally suited for the high inserting ureter, and present initial results.

A wide 1-2-cm side-to-side anastomosis is created between the dilated and elastic portion of the ureter just distal to the UPJO and the lower and dependent portion of the hydronephrotic renal pelvis. The UPJ is not disturbed and the renal pelvis is not surgically reduced. Since 2004, of 27 patients requiring surgery for UPJO, 7 underwent bypass pyeloplasty. The indications for surgery included increasing hydronephrosis or decreasing individual renal function in four, pain in two and pyelonephritis in one. The remaining 20 underwent a classic dismembered pyeloplasty.

During a mean follow-up of 26 months, the anteroposterior diameter of the repaired kidney decreased by a mean of 55%. The individual renal function in the repaired kidney improved in two and remained stable in the remainder.

These favorable initial results justify further exploration of this simplified technique and its adaptation for laparoscopic and robot-assisted approaches. Bypass pyeloplasty may be a more physiologic procedure in patients with mid to high insertion of the ureter.