Technique Clears Obstructed Ureters
Team reports an 85% rPCN success rate.
The procedure was performed in three stages: ultrasound and/or fluoroscopy-guided placement of antegrade nephrostomy/nephroureterostomy; transileal conversion of the antegrade catheter to an rPCN with an antegrade wire directed out of the stoma; placement of a temporary safety catheter that is capped for one month; and transileal exchange of the rPCN and removal of safety catheter.
The rPCN procedure is minimally invasive, reduces the need for externalized flank catheters and appliances for maximum patient comfort, and has high technical and clinical success rates. In addition, the researchers found that the success rates at their institution were similar to that of open surgery.
“Our success rates are high,” said lead researcher William Alago, MD, assistant attending physician in the department of radiology. “Most of these patients have bladder cancer and some have other pelvic cancers and we are able to see success rates above 85%. The technique is a good one and we believe the results are very promising.”
Dr. Alago and his team studied 49 patients with ureteral obstruction who underwent image-guided placement of 61 antegrade nephrostomy and/or nephroureterostomy catheters followed by attempted conversion to transileal retrograde nephrostomy catheters. The mean age of the patients was 70 (range, 50-86 years); 41 were male, eight were female and 12 patients had bilateral catheters.
Technical success was achieved in placing 56 of the 61 catheters (91.8%) and clinical success was observed in 42 patients (85.7%), with a mean clinical follow-up of 22 months (range, 2-132 months).
The researchers defined technical success as completion of all three procedural stages and clinical success as instances in which the rPCN served as the definitive treatment for the ureteroileal anastomotic stricture without the need for surgical intervention or conversion to an externalized flank catheter. The investigators classified complications as major or minor according to SIR standards.
No major complications occurred from initial placement. Minor complications during the initial three stages included pericatheter leakage and tube dislodgement, which occurred in two patients. In both cases, the problems were alleviated upon conversion to rPCN in stage 2.
Dr. Alago's group observed delayed complications in four patients (8.2%); these were mostly due to catheter encrustation. Two patients had urosepsis from catheter encrustation (4.1%), one patient had a dislodged catheter with hydronephrosis and pain, and one patient had tract bleeding following antegrade puncture to facilitate a difficult rPCN exchange.
“The gold standard remains open surgical revision, but not everyone is a surgical candidate,” Dr. Alago said. “So, we are mainly trying to see, for those patients who are not surgical candidates, if there is a viable means to have long-term success and now we actually think this three-step process is the way to go.”