Ultrasound-guided percutaneous nephrolithotomy: Advantages and limitations

The use of ultrasound in percutaneous nephrolithotomy (PCNL) has not been shown to translate to better clinical and stone outcomes. To compare the operative outcomes, postoperative outcomes and complication rates of ultrasound-guided access PCNL (USGA-PCNL) versus fluoroscopy-guided access PCNL (FGA-PCNL).

A total of 184 consecutive patients who underwent PCNL from July 2008 to September 2014 were identified from our PCNL database. Seventy-two patients underwent USGA-PCNL and 112 FGA-PCNL.

The patients were similar in age, sex, race, American Society of Anesthesiologists physical status classification, mean largest stone diameters, side of PCNL, number of stones and the degree of hydronephrosis between both groups. There were higher rates of upper pole (5.6% vs. 3.6%), mid pole (8.3% vs. 2.7%) and multiple pole punctures (4.2% vs. 0%) in USGA-PCNL compared to FGA-PCNL (p=0.027). There was no difference in the stone free rates of both groups in univariate analysis. Those who had FGA-PCNL were 2.26 (95% confidence interval, 1.09-4.75; p=0.029) times more likely to require a second-look procedure compared to USGA-PCNL on univariate analysis but not on multivariate analysis. There were no differences in Clavien-Dindo complications. No patient in the USGA-PCNL group experienced organ injuries during puncture compared to 1 patient in the FGA-PCNL group who had pneumothorax requiring urgent chest tube insertion.

The use of ultrasonography to guide access puncture during PCNL eliminates the risk of inadvertent organ injuries. Similar operative and stone outcomes show that the learning curve for USGA is minimal compared to conventional FGA.