Feasibility and safety of stone-guided puncture in percutaneous nephrolithotomy in a select group of patients

Background and rationale Percutaneous nephrolithotomy (PCNL) is the preferred treatment option for large kidney stones due to high stone-free rates. Usually, a contrast study via retrograde ureteral catheter (U-Cath) visualises the pelvicalyceal system (PCS) under fluoroscopy. Although U-Cath is recommended in conventional PCNL (cPCNL), modifications such as direct puncture with antegrade contrast pyelography or stone-guided puncture followed by contrast injection have been employed in different circumstances. However, there are safety concerns in performing stone-guided PCNL (sg-PCNL) ‘without contrast pyelography or ultrasound’. We aim to evaluate the safety and effectiveness of sg-PCNL in selected cases without contrast pyelography or ultrasound. Materials and methods This study reports PCNL outcomes in 57 patients with urolithiasis who underwent stone-guided puncture (sg-PCNL) by a single surgeon at a tertiary hospital. The puncture landmark was the calyceal stone (aimed at its distal margin), targeted end-on using the Bull’s eye technique, with the initial puncture needle (IPN) aligned along the stone’s long axis; the puncture was performed solely under fluoroscopic guidance. In addition to demographic features, procedural variables such as puncture time, number of punctures, operation time, haemoglobin drop, stone-free rate, and complications were recorded and analysed. Results The operation duration in the sg-PCNL cohort averaged 54.45 min, with most surgeons rating visualisation as excellent (96.4%). There was a minimal, non-significant decrease in haemoglobin (0.9 ± 0.7 g/dL, p = 0.32) and creatinine (0.3 ± 0.7 mg/dL, p = 0.442). Stone-free status was achieved in 94.6% of patients, with 5.4% having residual stones. The complication rate was 3.6%, all grade I ( p = 0.627). Guidewire patterns were ‘Ureteric line’ (U) in 67.9% and ‘Upper pole-pelvic’ (UP) in 32.1%. Conclusion sg-PCNL is a safe, effective alternative to traditional techniques in select patients when performed by an experienced surgeon.