RESUMEN
<p><b>OBJECTIVE</b>To discuss the optimal approach of percutaneous nephrolithotomy (PCNL) for treatment of complicated renal calculi.</p><p><b>METHODS</b>A total of 581 patients with complicated renal calculus were treated by PCNL through the upper pole calix access. Of the 581 patients, 55 had multiple upper pole calculi, 136 had staghorn stones, 145 had partial staghorn stones, and 245 had multiple renal calculi.</p><p><b>RESULTS</b>PCNL through the upper pole calix access was completed successfully in all the cases. Of these patients, 90.3% (525/581) were stone-free after a single access, with a total stone-free rate of 94.6% (550/581). Thirty-five patients needed two accesses, 10 needed 3 accesses, 2 required 4 accesses, and 1 patients had 5 accesses. The operative time ranged from 30 to 150 min (mean 45 min). The successful rate of puncture was 100% without occurrence of severe injury of the pleura, intestine, peritoneum or other adjacent organs.</p><p><b>CONCLUSIONS</b>Percutaneous nephrolithotomy through the upper pole calix access allows greater stone clearance rate due to its easy access into the intrarenal collecting system and can be an ideal approach for PCNL for complicated renal calculi.</p>