Supine percutaneous nephrolithotomy for bilateral complete staghorn calculi in an L-shaped cross-fused renal ectopic anomaly.

A 68-year-old woman was diagnosed to have a left-to-right L-shaped crossed-fused kidney with staghorn calculi in both renal moieties on evaluation for abdominal pain. She underwent supine percutaneous nephrolithotomy using 3 tracts in 3 stages. By using 3-dimensional reconstructed computed tomography urogram, proper preoperative planning, appropriate patient positioning, ultrasound-guided access, intraoperative traction, and flexible nephroscopy, complete stone clearance can be achieved in seemingly difficult stones in anomalous kidneys.