Abstract No. 570 Nephroureteral access prior to percutaneous nephrolithotomy for staghorn calculi: comparative study with non-staghorn calculi on feasibility, safety, and surgical outcomes

Abstract

To compare the feasibility and safety of nephroureteral (NU) access, and surgical outcomes between patients with staghorn calculi (SC) and those with nonstaghorn calculi (non-SC) who were treated with percutaneous nephrolithotomy (PCNL). Between April 2012 and December 2016, 152 kidneys in 139 patients (71 male 68 female, median age: 55 years) were percutaneously accessed for PCNL. Of these, 48 kidneys (32.6%) had SC (SC group) and 104 kidneys (68.4%) had non-SC (Non-SC group). A stone-bearing calyx was generally accessed at the referring urologist’s request. More than one access was obtained and used for PCNL in 9 kidneys (5.9%). The lower pole calyx was most frequently accessed (n = 116, 76.3%). Technical success rates of NU access (overall and through a stone-bearing calyx), fluoroscopy time (minutes), and incidence of complications related to NU access resulting in cancellation of scheduled PCNL were compared between groups. Stone clearance (no residual stones > 5 mm on post-PCNL imaging) and incidence of complications related to PCNL were also compared. The overall technical success rate of NU access and access through a stone-bearing calyx were not statistically different between groups (SC vs Non-SC: 93.8% vs 97.1% (P = .28), 87.5% vs 89.8% (P = .68), respectively). The mean fluoroscopy time (16.6 vs 14.6 minutes, p = .98) and incidence of NU access-related complications (10.4% vs 6.7%, p = .31) did not significantly differ between groups. Complications of NU access included urosepsis (5/48 vs 4/104, P = .11), bleeding (1/48 vs 2/104, P = .68) and others (n = 2 in Non-SC group). Stone clearance was significantly less achieved in SC group than Non-SC group (Stone clearance rate: 43.5% vs 67.3%, P = .01). Incidence of PCNL-related complications was not significantly different between groups (33.3% vs 23.8%, P = .22). NU access in patients with SC was as feasible as that with Non-SC without significant difference in incidence of complications or fluoroscopy time. Technical modifications of NU access (multiple accesses, upper pole access, etc.) may be necessary to increase stone clearance rate in patients with SC.