The Association of Stone Opacity in Plain Radiography with Percutaneous Nephrolithotomy Outcomes and Complications

To investigate the influence of stone opacity in plain radiography on stone free rate and complications ofpercutaneous nephrolithotomy (PCNL).

A number of 101 patients who underwent PCNL between July-September 2015 wereprospectively included. Stone opacity was judged on preoperative plain Kidney-Ureter-Bladder X-ray. Stone freerate was evaluated two weeks after the operation by ultrasonography and KUB.

There were 61 patients with opaque stones and 40 patients with non-opaque stones. The age, body massindex, preoperative creatinine, history of stone surgery, and stone size was not statistically different betweenpatients with opaque and non-opaque stones. Neither operation duration nor access numbers were statisticallysignificant between opaque and non-opaque stones. The frequency of stone free patients in opaque stones and nonopaquestones were 55/61 (90%) and 30/40 (75%) respectively (P = .04) The magnitude of hemoglobin drop inopaque stones and non-opaque stones were 1.9 ± 1.2 mg/dL versus 2.9 ± 1.7 mg/dL (P = .005).

The stone free rate is lower and the magnitude of bleeding is higher in PCNL of non-opaque stoneswhen compared to opaque stones if rigid instruments are used for nephroscopy.