Multislice computed tomography vs. intravenous urography for planning supine percutaneous nephrolithotomy: A randomised clinical trial

Objective: To compare the outcome of treatment planning using multislice computed tomography (CT) or intravenous urography (IVU) for supine percutaneous nephrolithotomy (PCNL). Patients and methods: The study included 60 patients with renal stones, all treated by supine PCNL, between March 2011 and October 2012. The patients were divided randomly into two equal groups; in group 1 30 patients had the PCNL access planned based on IVU findings, and in group 2 the PCNL access was planned based on multislice CT images. All patients were suitable for PCNL, based on a plainabdominal film and ultrasonography, and with a body mass index of 30 kg/m2. The exclusion criteria were renal anomalies and bleeding diathesis. All data from both groups for the mean time taken to gain percutaneous access, operative duration, fluoroscopic time, access difficulty, stone-free rate and intraoperative morbidity were collected and analysed statistically. Results: The mean (SD) time taken to gain percutaneous access was longer in group 1 than group 2, at 22.2 (1.76) vs. 13.1 (1.62) min (P 0.001), as were the operative duration, at 81.9 (14.9) vs. 58.8 (7.6) min (P 0.001), and fluoroscopic time, at 3.5 (1.7) vs. 2.2 (1.3) min (P = 0.002). In group 1 there were four cases (13%) in which there were difficulties in establishing percutaneous access, while in group 2 there were none (P = 0.003). There was intraoperative morbidity in three patients (10%) in group 1 and two (7%) in group 2. Conclusion: Multislice CT is a safer, more accurate and noninvasive imaging techniquethan IVU for mapping the pelvicalyceal system. It saves time and is essential in choosing the optimal percutaneous access into the pelvicalyceal system for a safe and successful PCNL.