Complex multiple renal calculi: stone distribution, pelvicalyceal anatomy and site of puncture as predictors of PCNL outcome

PURPOSE: Management of patients with complex multiple renal calculi has always remained challenging and they pose many difficulties during percutaneous nephrolithotomy (PCNL) like higher incidence of residual calculus and multiple tracts requirement. The aim of our study was to evaluate the impact of pelvicalyceal system (PCS) anatomy, stone distribution and the site of puncture on the outcome of PCNL in patients with complex multiple renal calculi. MATERIALS AND METHODS: One hundred and ten patients with complex multiple renal calculi undergoing PCNL during January 2015 to December 2015 were enrolled in our study. Pelvicalyceal anatomy and the stone distribution were determined from intravenous urography. PCNL was done using standard technique. We evaluated the impact of PCS anatomy, stone distribution and the site of puncture on the surgical outcome. RESULTS: Of all the studied pelvicalyceal anatomy variables, infundibular width, intercalyceal angle and PCS surface area affected the number of punctures. Stone distribution involving all the three calyces or middle and lower calyces was most unfavourable for achieving complete stone clearance. The middle calyceal puncture was almost equally good as the upper calyceal puncture in achieving stone clearance. With timely multiple punctures done, there was neither significant haemoglobin fall nor creatinine rise. CONCLUSION: Pelvicalyceal anatomy, stone distribution and site of puncture impacts the number of punctures required and stone clearance achieved in patients with complex multiple renal calculi undergoing PCNL. Based on these parameters we can predict which patient has a high likelihood of requirement of multiple punctures. With timely multiple punctures done, there is neither significant haemoglobin fall nor creatinine rise.