Impact of stone branch number on outcomes of percutaneous nephrolithotomy for treatment of staghorn calculi.

PURPOSE

To determine the impact of staghorn calculi branch number on outcomes of percutaneous nephrolithotomy (PNL).

MATERIALS AND METHODS

Retrospectively, we evaluated 371 patients (386 renal units) who underwent PNL for staghorn calculi. All calculi were showed with CT three-dimensional reconstruction (3DR) imaging preoperatively. From 3DR images, the number of stone branching into minor renal calices was recorded. According to the number, patients were divided into four groups. Group 1: the branch number 2-4; Group 2: the branch number 5-7; Group 3: the branch number 8-10; Group 4: the branch number >10. The number of percutaneous tract, operative time, staged PNL, intraoperative blood loss, postoperative hospital stay, complications, main stone composition, and stone clearance rate were compared.

RESULTS

A significantly higher ratio of multitract (p<0.001) and staged PNL (p<0.001), a longer operative time (p<0.001) and postoperative hospital stay (p=0.043), and a lower rate of stone clearance (p<0.05) were found in PNL for calculi with a stone branch number ≥5. There was no statistical difference in intraoperative blood loss (p=0.101) and main stone composition (p=0.546). There was no statistically meaningful difference among the four groups based on the Clavien complication system (p=0.46).

CONCLUSION

With the stone branch number more than five, the possibility of multitract and staged PNL, lower rate of stone clearance, and a longer postoperative hospital stay increases for staghorn calculi.