Munich, Germany (UroToday.com) Prediction of surgical outcomes following percutaneous nephrolithotomy (PCNL) is key. Additionally patients counseling and managing their expectations is of paramount importance. Several scoring systems have been developed to be used for PCNL outcomes, namely Guy's score, S.T.O.N.E nephrolithometry score and CROES nephrolithometric nomogram. Lim and colleagues performed a single center comparison of 3 scoring system to identify the most accurate in predicting surgical outcomes.
A retrospective review of 208 patients who underwent PCNL was performed at a single academic institution. Preoperative characteristics and outcomes were analyzed. All patients were evaluated with a plain kidney ureter and bladder (KUB) radiograph on post-operative day one. Stone free status is defined as no visible stones or residual fragments less than 4mm. Post operative complications were graded according to modified Clavien classification.
Results - All three scoring systems were able to successfully predict stone free status. (Guy's score, OR= 0.550, [95% CI 0.399- 0.759 ; p=0.000], S.T.O.N.E nephrolithometry score, OR= 0.795, [95% CI 0.681- 0.927 ; p=0.003 ], and CROES normogram, OR= 1.014, [95% CI 1.006- 1.022 ; p=0.001] )
Additionally, there was no significant difference in the areas under the curves when comparing the three scoring systems in predicting stone free status post PCNL. (Guy's score , 0.646 [95% CI 0.571–0.721] vs. S.T.O.N.E nephrolithometry score, 0.615 [95% CI 0.537- 0.693] vs CROES normogram, 0.645 [95% CI 0.570-0.720], p=0.480.)
Dr. Lim concluded that, given the equal predictive ability of all three scoring systems in the setting of PCNL, one should use the one he likes the most. Each scoring systems offers a unique design based on different imaging modalities. There limitations and advantages to each scoring system. But one should use the one he likes and finds the easiest to use during busy clinical routine.
Presented By:
Lim B.
Changi General Hospital, Dept. of Urology, Singapore, Singapore
Reported by
Zhamshid Okhunov, MD, at the 31st Annual EAU Congress - March 12 - 15, 2016 – Munich, Germany
UC Irvine Urology