Evaluation of stone-free rate using Guy’s Stone Score and assessment of complications using modified Clavien grading system for percutaneous nephro-lithotomy

Abstract

To prospectively evaluate the ability of Guy's Stone Score (GSS) in predicting stone clearance rate and complication rate (by modified Clavien grade) for renal stones treated by percutaneous nephrolithotomy (PNL). From January 2013 to June 2014, a total of 142 patients undergoing PNL were evaluated prospectively. Patients with co-morbidities like hypertension, diabetes, renal failure were excluded from the study. All patients were classified according to GSS based on the findings of pre-operative intravenous urography (IVU) and per-operative retrograde pyelography (RGP). All PNL procedures were done by standard technique in prone position and success was defined as no residual stone visible on X-ray KUB done on the third postoperative day. Complications were classified according to modified Clavien grading system. The initial stone clearance rate was 71.1% and overall final stone clearance rate was 90.14%. The complication rate according to Clavien grading system was 40.1%. The final stone clearance rates were 93.9, 85.71, 90.47, and 77.77% in GSS I, II, III, and IV, respectively (p<0.001, <0.05, <0.05 and >0.05, respectively). The Clavien complication rates were 23, 61, 52, and 77.7% in GSS I, II, III, and IV, respectively (p<0.001). The GSS is a simple and easily reproducible system to preoperatively predict stone-free rate and perioperative complication rate. It helps in better patient counseling preoperatively.

External validation and comparison of the scoring systems (S.T.O.N.E, GUY, CROES, S‐ReSC) for predicting percutaneous nephrolithotomy outcomes for staghorn stones: A single center experience with 160 cases

“…However the authors revealed no correlation between SFR and Guy score. In a previous study, the authors advocated that although Guy scoring system (GSS) was highly effective in predicting stone free status, it was inefficient to predict CR [23]. In the current study, a positive correlation was found between Guy and SFR in multivariate analysis.…”

“…In a previous study, the authors revealed a significant correlation between S.T.O.N.E nephrolithometry score and SFR and bleeding [23]. Farhan et al.…”

“…In a previous study, the authors revealed a significant correlation between S.T.O.N.E nephrolithometry score and SFR and bleeding [23]. Farhan et al found significant association between S.T.O.N.E score and SFR and operation time respectively [24].…”

Inter-observer variability amongst surgeons and radiologists in assessment of Guy’s Stone Score and S.T.O.N.E. nephrolithometry score: A prospective evaluation

“…The main drawback of these systems is that none of them is perfect. Most of the published studies have focussed on re-validating them or comparing these systems with one another on the basis of individual parameters, ability to predict the stone-free rate (SFR), and complications [6][7][8][9][10][11][12][13][14][15][16][17][18]. Few have attempted to compare the agreement between different groups of trainees and surgeons [5,19].…”

Can renal stone size and the use of the nephrolithometric system increase the efficacy of predicting the risk of failure of percutaneous nephrolithotripsy?

“…Although total fragmentation is expected, it is not always possible, and additional procedures are necessary, in special in staghorn or multiple calix stones 2 . Size of the stone, calix involvement, calix and pelvic anatomy, and anatomic malformations orient the feasibility of different treatments and impact surgical results 3,4 .…”